Policy Research Working Paper                               11070




Effects of a Community-Driven Water, Sanitation,
      and Hygiene Intervention on Diarrhea,
       Child Growth, and Local Institutions
        A Cluster-Randomized Controlled Trial in Rural
                Democratic Republic of Congo

                            John P Quattrochi
                               Kevin Croke
                              Caleb Dohou
                            Luca Stanus Ghib
                             Yannick Lokaya
                              Aidan Coville
                             Eric Mvukiyehe




 Development Economics                          A verified reproducibility package for this paper is
 Development Impact Group                       available at http://reproducibility.worldbank.org,

 February 2025                                  click here for direct access.
Policy Research Working Paper 11070


  Abstract
 Diarrhea and growth faltering in early childhood reduce                                  The percentage of villages in the intervention group with
 survival and impair neurodevelopment. This paper assesses                                an active water, sanitation, and hygiene (or just water)
 whether a national program in the Democratic Republic                                    committee was 21 percentage points higher than the con-
 of Congo reduced diarrhea and stunting and strength-                                     trol group. Households in the intervention group were 24
 ened local water and sanitation institutions. The program                                percentage points more likely to report using an improved
 combined (i) funds for latrine and water upgrades, (ii)                                  water source, 18 percentage points more likely to report
 institutional strengthening activities, and (iii) behavior                               using an improved sanitation facility, and reported more
 change campaigns. In 2018, the program was randomly                                      positive perceptions of water governance. The Democratic
 assigned, after stratifying by province and cluster size, with                           Republic of Congo’s national rural water, sanitation, and
 50 intervention and 71 control clusters. In 2022–23, 3,283                               hygiene program increased access to improved water and
 households were interviewed, at a median of 3.6 years                                    sanitation infrastructure, and created new water, sanitation,
 post-intervention. The intervention had no effect on diar-                               and hygiene institutions, all of which persisted for more
 rhea and no effect on length-for-age Z-scores in children.                               than three years. However, these effects were not sufficient
 Villages in the intervention group had a 0.40 higher score                               to reduce diarrhea or growth faltering.
 on the water, sanitation, and hygiene institutions index.




 This paper is a product of the Development Impact Group, Development Economics. It is part of a larger effort by the
 World Bank to provide open access to its research and make a contribution to development policy discussions around the
 world. Policy Research Working Papers are also posted on the Web at http://www.worldbank.org/prwp. The authors may be
 contacted at acoville@worldbank.org. A verified reproducibility package for this paper is available at http://reproducibility.
 worldbank.org, click here for direct access.




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         issues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry the
         names of the authors and should be cited accordingly. The findings, interpretations, and conclusions expressed in this paper are entirely those
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                                                       Produced by the Research Support Team
    Effects of a Community-Driven Water, Sanitation, and Hygiene Intervention on Diarrhea,
     Child Growth, and Local Institutions: A Cluster-Randomized Controlled Trial in Rural
                               Democratic Republic of Congo

John P Quattrochi 1, Kevin Croke 2, Caleb Dohou 3, Luca Stanus Ghib3, Yannick Lokaya3, Aidan
Coville3, Eric Mvukiyehe4




1 Graduate School of Arts & Sciences, Georgetown University
2 Department of Global Health & Population, Harvard TH Chan School of Public Health
3 Development Impact (DIME) Department, World Bank
4 Department of Political Science, Duke University
Corresponding author is Aidan Coville (acoville@worldbank.org). This paper was made possible through
collaboration between the Foreign, Commonwealth, and Development Office (FCDO-DRC), FCDO’s Evaluation Unit,
the United Nations Children's Fund (UNICEF-DRC), the VEA Coordination Team from DRC’s ministries of Health and
Education, and the World Bank's Development Impact Department (DIME). We thank the continued leadership,
and persistent efforts of several members from these organizations. This study was funded by FCDO - DRC under
the World Bank-administered i2i Trust Fund. DIME Analytics conducted a reproducibility review of the data and
results in this paper. The study received ethical clearance from IRB Solutions (Protocol \#2019/10/20) and from the
Research Center for Health Promotion (CRPS) Institutional Ethical Committee (CEI) of the Institut Supérieur des
Techniques Médicales de Bukavu (ISTM-Bukavu) in the DRC, and a Health Research Approval from the DRC
Ministry of Health. The findings, interpretations, and conclusions expressed in this paper are entirely those of the
authors. They do not necessarily represent the views of the World Bank and its affiliated organizations, or those of
the Executive Directors of the World Bank or the governments they represent.
                                                                                                    2



Introduction
The most recent estimates of the global burden of morbidity and mortality attributable to unsafe
water, sanitation, and hygiene (WASH) are that 1.4 million deaths and 74 million disability-
adjusted life years lost could have been prevented in 2019 [1]. People living with unsafe WASH
have higher exposure to fecal-oral pathogens, resulting in enteric dysfunction, diarrheal illnesses,
and, in children, growth faltering. Growth faltering, in turn, has long-term negative impacts on
health, cognition, and human capital [2,3]. In 2020, 2.0 billion people did not have access to safely
managed drinking water services, 3.6 billion did not have access to safely managed sanitation
services, and 2.3 billion did not have access to handwashing facilities with soap and water at
home [4,5]. While access has been increasing, progress will need to accelerate by three-to-six-
fold to meet the Sustainable Development Goals for 2030 [6]. The challenge of increasing access
is particularly acute for people living in or near armed conflict – one in six people worldwide – both
through the direct effects of conflict and because violence and insecurity impede collective action
to provide public goods like WASH [7,8]. In the Democratic Republic of Congo (DRC), as of 2020,
48 million people still lacked basic drinking water services, 11 million people still practiced open
defecation, and 72 million people still lacked basic hygiene services [9].

To increase access to safe WASH, governments and donors have increasingly turned to
community-led approaches. While WASH experts called for greater community participation for
over 30 years [10], the sector did not fully embrace this approach until the late 1990s. Beginning
with community-led total sanitation in Bangladesh in 1999, community-led WASH programs have
been implemented in at least 60 countries, and 15 countries have incorporated them into national
policy [11,12].

Despite this broad adoption, the health effects of community-led WASH interventions – and of
many WASH interventions in general – remain poorly understood. The accumulation of evidence
has accelerated in recent years, but the length of the causal chain from the intervention to the
outcome, and the vast design space for WASH interventions (which can incorporate behavior
change campaigns, infrastructure, institutions, and/or new technologies), means that many
fundamental questions remain unanswered. A meta-analysis of 13 randomized WASH trials found
no effect on child length-for-age, but a meta-analysis of 124 WASH studies (randomized and
observational) found a protective effect against diarrhea [11,13–24]. There is a great deal of
heterogeneity in effect size across studies, likely due to variation in intervention components and
intensity, and to the influence of contextual factors such as baseline exposure to fecal matter.

To our knowledge, this is the first trial of an intervention that combines the creation of new
institutions, funding for new or improved infrastructure, and a behavior change campaign, all
within a locally-led process of targeting and implementation. We study this complex intervention
as it is implemented at scale, providing a realistic estimate of effectiveness for policy makers in
similar contexts. Our follow-up period is unusually long (3.6 years), enabling us to address the
question of sustainability. We also provide evidence in a conflict-affected setting, where WASH
interventions have rarely been evaluated using experimental designs.
                                                                                                    3


The intervention is the ‘healthy villages’ component of the DRC’s Healthy Villages & Schools
program, co-led by the Ministries of Public Health, and of Primary, Secondary, and Professional
Education, with support from the United Nations Children’s Fund (UNICEF). Since 2008, nearly 9
million people in almost 11,000 villages have been reached with WASH services through the
program. Healthy Villages & Schools was the largest WASH program implemented by UNICEF
globally and comprised 90% of total external funding committed to rural WASH in the DRC from
2005 to 2020 [25]. Our goal was to estimate the effect of Healthy Villages & Schools on diarrhea
prevalence, child length-for-age, and WASH institutions.


Methods

Study design and participants
The intervention of interest is a DRC government-run program that began several years before
our study. For our study, the government agreed to randomly assign the next phase of the
program (i.e. the next group of villages to receive the intervention). In 2018, we randomly assigned
groups of villages to intervention or control (details below). Since we did not collect any data prior
to randomization, we did not yet register the study. We collected the first round of data in late
2019, about 5 months after the intervention was implemented (implementation took about one
year in each group of villages) [26].

We pre-registered the analysis of that first round of data collection (5 month follow-up), before
any of the authors saw the data, in the American Economics Association (AEA) Registry
(AEARCTR-0004648) (https://www.socialscienceregistry.org/trials/4648).

In Feb 2021, we registered plans for additional data collection in the Pan-African Clinical Trials
Registry                                                              (PACTR202102616421588;
https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=14670). In April 2023, before the PIs had
seen any data for the 3.6-year follow-up (i.e., the data for the current manuscript), we updated
the registration with our primary and secondary outcomes. In April 2023, we also posted our pre-
analysis plan for the 3.6 year follow up on the AEA Registry (see "Three Year Follow up Pre-
Analysis Plan" at https://www.socialscienceregistry.org/trials/4648). All planned studies from this
project are now registered and any future work will be registered prospectively.

This study is reported as per CONSORT guideline (S1 Text).

We worked with intervention implementers to design a cluster-randomized trial in rural villages in
five DRC provinces: Kongo Central, Kasai, Kasai Central, North Kivu, and South Kivu. The
implementers identified 403 candidate villages in which the intervention could be launched during
the study period, based on the established criteria for the intervention: that the village was located
in a secure and accessible Health Area that was not already served by the WASH Consortium,
the Health Area staff were dynamic and interested in participating, and there was a problem of
diarrhea, cholera, and/or malnutrition. Among these villages, 34 already had program activities in
process before research activities began, leaving 369 eligible villages.
                                                                                                      4


To avoid spillover effects from treatment villages to control villages, we grouped those villages
into clusters. We considered any villages within 2.5 km of each other (using Euclidean distance
between village centroids) to be part of the same cluster. Therefore, all clusters have at least 2.5
km between them. We relax this rule in South Kivu, where density is greater, and use a minimum
distance of 1km. In total, this resulted in 124 clusters. North Kivu had only three clusters (covering
30 villages); as a result, it was not logistically feasible to include these villages in the trial. That
left 121 clusters (339 villages) in four provinces.

Each village in the intervention clusters received the intervention, as described above. Villages in
control clusters did not receive any intervention. Data collection procedures were identical in the
two groups.

The study protocol was approved by the Institutional Ethics Committee of the Institut Superieur
des Techniques Médicales de Bukavu (DRC) (#001/2019 & #008/2022) and by Solutions IRB
(USA) (#2019/10/20). With direction from the study investigators, Innovative Hub for Research in
Africa (IHfRA) was responsible for data collection. No study data was collected by intervention
implementers.

All residents of the targeted villages who had lived in the village for at least four years (i.e., moved
to the village prior to the intervention) were eligible to participate in the study. Two groups of
households were interviewed: households that were interviewed at 5 months post-intervention (4
per village) and households that had not been previously interviewed (6 per village). Both groups
were randomly selected (at their respective entries into the study) as follows: from the center of
the village, interviewers went in opposite directions to the nth household, where n was a randomly
selected number between 1 and 20. We interviewed the head woman of the household. We also
asked to measure the height and weight of the youngest child aged 2-5 years, or, if none, the
oldest child aged 0-2 years. Adult participants provided informed consent verbally, which was
recorded electronically.

Randomization and masking
A total of 339 villages in 121 clusters were eligible for randomization. In all provinces except Kasai
Central, each cluster was given equal probability of being selected for treatment or control. In
Kasai Central, due to budget constraints, we increased the probability of being selected into the
control group to 75%, to reflect the fact that only 16 out of 81 villages could receive the
intervention. Thus the allocation probability for the intervention group was 25%.

We block randomized by province and number-of-villages-per-cluster (12 blocks total; see S1
Table). Since randomization was based on clusters but the implementing organization’s
operational targets were based on villages, it was not possible to force the randomization to select
the exact number of villages targeted without introducing potential bias. Instead, we compared
the number of target villages per province to the number of treatment villages selected after
randomization. In cases where the number of intervention villages was larger than the operational
target, we randomly dropped an equal number of intervention villages from the largest control and
intervention clusters until operational targets were met. We dropped 2 villages in Kongo Central
and 4 villages in Kasai. We also dropped one control village in Kasai due to a coding error. This
left 146 villages in 50 clusters in the intervention group, and 186 villages in 71 clusters in the
                                                                                                                    5


control group. S1 Table shows how intervention and control villages and clusters are distributed
across provinces. Randomization was done by the research team in Stata.

Due to the participatory and visible nature of the intervention, neither participants nor data
collectors were masked to treatment status. However, data collectors did not participate in
intervention implementation and were employed by a separate, independent organization.

Procedures
The intervention, “Healthy Villages & Schools”, was developed by the DRC government and
UNICEF. We focused on the village rather than the school component. This program mobilizes
communities to become a “Healthy Village” with 3-6 months of support from government health
officials and local NGOs, including approximately $2,000 of financing for new or improved water
infrastructure, $2,000 for new or improved sanitation infrastructure, and $3,000 for personnel
costs, per village. The mean village size in the intervention group was 456 people (median 400;
IQR 502). The seven norms to become a Healthy Village are:

1. There is a dynamic village WASH committee.
 2. At least 80% of the population has access to safe drinking water.
 3. At least 80% of households use a hygienic latrine.
 4. At least 80% of households dispose of their household waste hygienically.
 5. At least 60% of the population washes their hands before eating and after going to the
latrine.
 6. At least 70% of the population is aware of fecal-oral disease transmission and how to
prevent this.
 7. The village is cleaned at least once a month.

The program is implemented in nine steps (Table 1) [27].

Table 1. The Healthy Village and Schools Program’s Nine Steps

 Step    Description

 0       The community learns about the program and collectively decides to adopt it before submitting a formal
         request to the relevant Health Zone. (A Health Zone is a geographic unit of the Congolese health system
         that contains roughly ten Health Areas and 100,000 residents, run by a Chief Medical Officer (CMO)).
         Program protocols state that the entire community should be involved in the decision to participate.

 1       A statement of agreement between the community and the Health Zone is signed.



 2       Health Zone officials survey 19 households on knowledge, attitudes, and practices (KAP). The community
         self-evaluates on eight practices, including handwashing, water use, and sanitation.



 3       The community spends about 11 hours over five days creating calendars and maps, visiting water points,
         classifying hygienic practices as healthy or unhealthy, discussing fecal-oral disease transmission,
         calculating medical costs, and assessing which individuals and organizations influence sanitation and
         hygiene in the community. This includes 1.5-2 hours in a facilitated activity around the question, “What are
         the hygiene practices that we want to change in our village?”
                                                                                                                     6



 4      The Health Zone provides training for 20 volunteers on maintenance of latrines, water supply systems, and
        sanitation, conflict management, and petty cash management. The community elects a village WASH
        committee.



 5      The community spends ten hours over three days describing a community vision, analyzing the barriers to
        reducing diarrheal diseases, choosing improvements to drinking water, sanitation, and hygiene, and
        formulating an action plan. The community is asked to identify practical, low-cost solutions with a minimum
        of outside assistance. New infrastructure is evaluated in terms of accessibility, technical feasibility, and
        technical capacity.



 6      The community builds new infrastructure over 90-180 days, supported by project funds. Key messages
        about sanitation and hygiene are discussed during sensibilization meetings or during visits to families by
        the WASH committee, community health workers, or other volunteers. Health Zone staff are expected to
        visit the community monthly during this time; Health Area staff weekly.



 7      The community self-evaluates again, to measure progress since Step 2. The Health Zone conducts
        additional KAP surveys and hosts three hours of meetings to assess the findings and make a plan to
        maintain progress.



 8      The CMO spends one day in the community to assess whether or not the community has completed its
        action plan and achieved the seven norms. If they have, a certification ceremony is held. The CMO and the
        village WASH committee develop a Community Action Plan for Maintenance so that the changes achieved
        through the program can be sustained over time.




The IHfRA data collection team used electronic tablets and transmitted data to a cloud-based
server, allowing the research team to conduct quality control measures in real-time, checking for
consistency and errors. Additionally, IHfRA randomly selected 15% of villages for a second round
of interviews, by different interviewers, with a shorter questionnaire, to check consistency across
key variables. Separately, children from two households per village had their height and weight
re-measured by an IHfRA supervisor, as a quality check.


Outcomes
Primary outcomes were caregiver-reported diarrhea in the last seven days among all children
who were under 5 years old at the time of the survey, length-for-age Z score for a randomly
selected child in each household, and a WASH governance index. If the household had one child
between age 2 and 5, we measured the length and weight of that child. If the household had more
than one child between age 2 and 5, we randomly selected one child. If the household had no
children between ages 2 and 5, but one or more children between ages 0 and 2, we measured
                                                                                                     7


length and weight of one of those children (randomly selected). Salter scale (Model 235 6S) and
wall-mounted measuring rods (portable baby/child length/height measuring system) were used.

The WASH governance index combined questions about the presence of a water committee,
frequency of committee meetings, WASH expenses (excluding maintenance), presence of a
maintenance plan, whether the committee tracks health conditions in the community, and whether
it tracks hygiene and sanitation.

Secondary outcomes were access to improved water and sanitation facilities, water quality at
water points and in homes, hygiene knowledge and behaviors, observed handwashing,
perceptions of WASH governance, children’s school absenteeism, child weight-for-age Z score,
and child weight-for-height Z score.

Structured observation of handwashing was done in four households per village. We first
attempted to observe the four households that were interviewed at the five-month follow-up; if any
were unavailable or unwilling, we randomly selected from the six new households to replace them.
A research assistant spent two hours in each of these households, recording if handwashing
occurred at critical junctures such as before preparing food (see S8 Table for full list of junctures).
This took place before the interview, to minimize Hawthorne effects.

Access to improved water and sanitation was self-reported, i.e. respondents reported whether
their main water source is improved or not according to the Joint Monitoring Program standard
definitions (e.g. boreholes are considered improved, while unprotected springs or surface water
sources are not). Cost paid by households for water and time spent collecting water were also
self-reported.

To measure water quality, we tested samples collected (i) at each of the water points used by
members of each village, and (ii) at household water storage containers in six randomly selected
households per village, on average. Testing was done concurrently with the household interviews.
We used the Aquagenx Compartment Bag Test E. Coli +Total Coliform Most Probable Number
(MPN) Kit. This measured the MPN of fecal indicator bacteria [28].

To measure subjective performance of local WASH institutions, we used survey questions about:
fairness of selection of water governance entity, perception of fair treatment, confidence in the
entity’s management of money, confidence in the entity’s response to infrastructure breakdowns,
confidence in management, and overall satisfaction. The data collection team also directly
observed water point functionality. Length of breakdowns was reported via a water committee
and village leader survey.

Statistical analyses
The number of village clusters in the study was determined by the program budget and proximity
of villages to one another (details above). Sample size calculations were used to determine how
many households in each village should be interviewed. Based on the primary outcome of
diarrhea prevalence, with a minimum detectable effect of 8 percentage points (pp), 32%
                                                                                                   8


prevalence in the control group (based on the 5-month follow-up results), intracluster correlation
of 0.09 (based on 5-month follow-up), and 1.3 children under 5 years per household (based on 5-
month follow-up), we required 10 households per village.

We estimated intervention effects according to random assignment (intention to treat),
irrespective of adherence to the intervention.

For both primary and secondary outcomes, whether binary or continuous, we fitted linear models
with a binary variable indicating whether the participant was in a treatment or control cluster [29].
Because randomization was stratified by province and number-of-villages-per-cluster, we
included binary variables (fixed effects) for each stratum (n=12) in the model. We also included
gender and age (month) indicator variables for all child health outcomes. We clustered standard
errors at the cluster (i.e. group of villages) level.

For the primary outcome of WASH institutions, and secondary outcomes consisting of multiple
measures, we calculated a summary index to avoid over-rejection of the null hypothesis due to
multiple inferences. We rescaled each outcome so that higher values implied better outcomes,
and averaged standardized values relative to the control group. Treatment effects were estimated
as the difference in the summary index between treatment and control groups, such that treatment
effects are expressed in standard deviation units relative to the control group.

We pre-registered two analyses restricted by subgroup: by province (for all three primary
outcomes), and by gender (for diarrhea and length-for-age). We test for interaction on the additive
scale, using interaction terms in linear models.

Statistical analyses were conducted in Stata version 16.0.

Role of the funding source
This study was funded by the UK Foreign, Commonwealth, and Development Office (FCDO)
(https://www.gov.uk/government/organisations/foreign-commonwealth-development-office), via
Amendment No. 3 to the Supplemental Arrangement with the World Bank regarding Multi-Donor
Trust Fund for Impact Evaluation to Development Impact (TF072617, parallel to TF072161). AC,
KC, and EM were staff at Development Impact at that time. The Healthy Villages & Schools
program was a DRC government national program funded by UK’s FCDO and implemented with
UNICEF’s support. The funder and implementing partners provided inputs at the design stage to
ensure the study addressed policy and program priorities of importance to them. The funders had
no role in data collection and analysis, decision to publish, or preparation of the manuscript.


Results
Of the 1,312 respondents in 328 villages interviewed for the 5-month follow-up, 1,133 (86%) in
328 villages were re-interviewed at the 3.6-year follow-up, between November 24, 2022 and
February 10, 2023 (Figure 1). We also reached two villages that were not accessible during 5-
month follow-up and lost one village that was surveyed at 3.6-year follow-up due to conflicts. In
39 households with a 5-month follow-up interview, a new respondent was interviewed at 3.6
                                                                                                                                                     9


years, and 140 households (11%) were replaced between 5-month and 3.6-year follow-ups.
Additionally, in each village at the 3.6-year follow-up, six never-previously-interviewed households
were randomly selected, conditional on having lived in the village for at least four years, yielding
1,970 interviews (in four villages, only five households were reached). Thus, at 3.6 years, we
interviewed a total of 3,283 households. Of those households, 75% (2,466 out of 3,283) had at
least one child eligible for a caregiver’s reports of diarrhea, and 72% (2,374 out of 3,283) had at
least one child eligible for length and weight measurement. The primary outcome of WASH
institutions was measured in 329 villages. In the intervention group, the median time since the
completion of Healthy Villages Step 6 (construction of infrastructure) was 3.6 years (IQR = 3.4 to
3.7).

At 3.6 years, respondents in intervention and control groups were similar with regard to
characteristics unlikely to be affected by the intervention, such as marital status, educational
attainment, age, religion, household size, and home construction materials (Table 2).

Table 2. Household and respondent characteristics by intervention group, at 3.6-year follow-up
                                                                 Control                             Intervention

 Outcomes                                             n           Mean            SD        n           Mean            SD      Adj. Diff.   p-value
 Household has improved roof                        1843          0.42           0.49     1436          0.47           0.50       -0.01       0.81
 Household has improved wall                        1845          0.01           0.09     1438          0.01           0.12       0.01        0.18
 Household has improved floor                       1816          0.04           0.19     1430          0.08           0.27       0.03        0.11
 Household size                                     1845          7.20           2.86     1438          7.18           2.93       0.03        0.80
 Respondent identifies as Catholic                  1845          0.18           0.38     1438          0.19           0.40       0.02        0.54
 Respondent identifies as Protestant                1845          0.31           0.46     1438          0.32           0.47       -0.06       0.05
 Respondent identifies with other religion          1845          0.02           0.15     1438          0.03           0.18       0.01        0.26
 Respondent age                                     1845           40           13.39     1438           40           13.07       0.72        0.25
 Respondent has completed primary school            1845          0.31           0.46     1438          0.34           0.48       -0.02       0.50
 Respondent has completed secondary school          1845          0.06           0.23     1438          0.07           0.25       0.00        0.78
   Respondent is married or cohabitating               1845             0.83           0.37    1438           0.82         0.38        -0.01      0.49
Adj. diff. = adjusted difference between intervention group and control group, estimated with models that include controls for randomization
blocks based on province and number of villages per cluster, and standard errors clustered by cluster. There were 121 clusters in total. Improved
roof=1 if roof is finished roofing (i.e., metal, wood, calamine/cement fiber ceramic tiles, cement or roofing shingles); improved walls=1 if walls are
‘finished walls’; improved floor=1 if floor is ‘finished floor’. All variables are binary except ‘HH size’ and ‘respondent age’; for these binary
variables, the mean represents the proportion of respondents who are in the listed category.


In the intervention group, 96% of villages reported that they created a community action plan and
prioritized actions to improve WASH (as instructed by the program); 86% reported that they had
implemented that plan.

The intervention had no effect on diarrhea (adjusted mean difference -0.01 [95% -0.05– 0.03])
(Table 3). Diarrhea prevalence was high overall, at 38% in the treatment group and 42% in the
control group. The intra-cluster coefficient (ICC) for diarrhea in the control group was 0.05; in the
intervention group, 0.07.
                                                                                                                                    10


Table 3. Intervention effects on primary outcomes: diarrhea, length-for-age, and WASH institutions

                                             Control                                 Intervention
Outcomes                       n    Prevalence/Mean SD            ICC     n   Prevalence/Mean SD            ICC     ITT     CI 95%
Diarrhea prevalence          2310           42%                  0.05 1762            38%                   0.07 -0.01 -0.05 0.03
Length-for-age Z-score 1223                -2.18          1.60 0.04 919               -2.20          1.59 0.06 -0.01 -0.15 0.12
WASH institutions index 185                 0.00          1.00 0.47 144               0.46           0.75 0.11 0.40 0.16 0.65

ITT = intention-to-treat effect estimate; ICC =intracluster correlation; HH = household. Effects are estimated with models that
include controls for randomization blocks based on province and number of villages per cluster. There were 121 clusters in total.
The WASH institutions index was calculated by rescaling each variable in the index (eg, presence of WASH committee) so that
higher values imply better outcomes, then standardizing relative to the control group, following Kling et al. Effects are in standard
deviation units.




The intervention had no effect on length-for-age Z-scores in children (adjusted mean difference -
0.01 [95% CI -0.15–0.12]). In the control group, the mean length-for-age Z-score was -2.18 (1.60
SD) (Figure 2). The ICC for length-for-age Z-score in the control group was 0.04; in the
intervention group, 0.06.

Villages in the intervention group had a 0.40 higher score on the WASH institutions index (95%
CI 0.16–0.65). The percentage of villages in the intervention group with an active water,
sanitation, and hygiene (or just water) committee was 21 pp higher than the control group. The
ICC for the WASH institutions index in the control group was 0.47; in the intervention group, 0.11.

Households in the intervention group were 24 pp (95% CI 12–36) more likely to report using an
improved water source, 18 pp (95% CI 10–25) more likely to report using an improved sanitation
facility, and reported more positive perceptions of water governance (adjusted difference 0.19 SD
[95% CI 0.04–0.34]) (Table 3). The more positive perceptions of water governance were driven
by higher reported satisfaction with water access (0.56 points higher (95% CI 0.27–0.85) on a 1-
5 scale). Intervention group households were also 9 pp more likely to report paying for water (95%
CI 0-19). Conditional on paying for water, there was no difference in the amount paid between
the intervention and control groups. The intervention had no effect on time spent collecting water.

Intervention group water points were 11 pp less likely to be currently functional (95% CI -0.18– -
0.05); 97% of water points in control villages and 85% of water points in intervention villages were
functioning.

Intervention group respondents scored 0.23 higher (95% CI 0.12–34) on the index of self-reported
hygiene & behavior index. This was driven by several measures. The intervention group was 3
pp more likely to report treating their water (95% CI 1–5), and 9 pp more likely to report
handwashing with soap or ash at least once in the previous day (95% CI 6-13). The intervention
group also scored 0.43 points higher (95% CI 0.19–0.67) on the handwashing knowledge scale
(range 0-10). However, in structured observations of handwashing behavior, there was no
difference between intervention and control households in measures of any observed
handwashing or handwashing with soap or ash.

Water samples from intervention village water points showed a small but statistically significant
improvement in thermotolerant coliforms per 100mL compared to control village samples (-0.17
adjusted mean difference in log10(MPN); 95% CI -0.32– -0.02). Overall water quality was low,
                                                                                                  11


even from improved sources. Among unimproved sources, 86% of samples had coliform levels
over 100 per 100mL, ‘very high risk’ according to WHO standards [30]; among improved sources,
60% of samples had coliform levels over 100 per 100mL. Water samples from intervention
household water containers showed no difference in thermotolerant coliforms per 100mL
compared to control household samples.

The intervention had no effect on the psychological well-being index, the life satisfaction & self-
esteem index, or school attendance.

In the prespecified subgroup analysis of primary outcomes by province, we find that the
intervention reduced diarrhea in one of four provinces (Kongo Central), reduced length-for-age in
one province (Kasai Central), and increased the WASH institutions index in two provinces (Kasai
and Kasai Central) (see S3 Table). We also used interaction terms in linear models to test for
effect modification on the additive scale (S5 Table). Of the nine coefficients (three provinces,
leaving out a reference, and three primary outcomes), two were statistically significant: in Kasai
Central province, the results suggest that the intervention increased diarrhea prevalence relative
to the treatment effect in the reference province (Kongo Central); in Kasai province, the results
suggest that the intervention increased length-for-age. For both diarrhea and length-for-age, the
Wald test rejects the null hypothesis that all province-by-intervention coefficients are zero at the
0.05 level. For the WASH institutions index, the Wald test fails to reject the null.

In the prespecified subgroup analysis of diarrhea and length-for-age by child sex, we find no
difference in intervention effects by sex (see S4 Table). In linear models with interaction terms for
intervention-by-sex, the coefficients are not statistically significant (S7 Table).


Discussion
We tested the effects of the national community-led rural WASH program in the DRC on child
length-for-age, diarrhea, and WASH institutions. The program improved community WASH
institutions, with intervention villages more likely to have a WASH committee, and for this
institution to actively monitor community health conditions. Intervention villages also had greater
access to improved water and sanitation infrastructure as a result of the program. However, we
cannot reject the null hypothesis that the intervention did not have any effect on child length-for-
age or diarrhea.

The finding of no effect on length-for-age is consistent with a recent meta-analysis of 11 WASH
trials with length-for-age as a primary outcome that found an adjusted mean difference in Z-score
between intervention and control of 0.00 (95% CI -0.03–0.04) [13]. These trial results stand in
contrast to many observational studies finding that WASH protects against growth faltering [31].
This suggests that the observational results may be confounded by other household or community
characteristics.

We measured fecal indicator bacteria in water sources and household water containers. We found
no difference between the intervention and control group household water quality, despite the fact
that intervention households were 24 pp more likely to use an improved water source. This is
likely due to the fact that improved water sources in our study had low-quality water, consistent
with evidence from DRC [25] and elsewhere [33]. It may also be linked to recontamination of water
                                                                                                    12


between collection and its ultimate use in the household. Overall, intervention water points had
only slightly lower levels of fecal indicator bacteria than control water points; log10MPN/100mL
was 0.17 lower in intervention water points (95% CI -0.32– -0.02), with a mean of 1.71 in the
control group. This is consistent with a meta-analysis of five WASH trials that found only a 6%
reduction in prevalence of enteropathogens in environmental samples [32].

In addition, two-thirds of our respondents reported spending at least one day per week working
on an agricultural plot (modal response = 4 days). Of those who did, 95% report open defecation
while in the field, and 91% report drinking from surface water or unprotected springs. This
highlights the challenge of delivering safe and comprehensive WASH services in some
agricultural settings.

Our finding of no effect on diarrhea contrasts with a meta-regression (conducted as part of a
systematic review) which found use of an off-site improved water source reduces the relative risk
of diarrhea by 19% compared to unimproved water [14]. The same analysis found that basic
sanitation without sewer connection lowered the relative risk of diarrhea by 21% relative to
unimproved or limited sanitation, which also contrasts with our results, while hygiene interventions
reduced the relative risk of diarrhea by 30%. However, another review found that effective
handwashing promotion typically requires daily to fortnightly contact between the promoter and
participant [31]. It is possible that our intervention achieved that frequency of contact during the
most intensive 90-180 days of implementation, but also likely that effects would have faded out
by our measurements over three years later.

We found no effect of the intervention on handwashing with soap or ash during structured
observations of study participants by our research team. However, participants in the intervention
group were 9 pp more likely to report washing with soap or ash the previous day. This underscores
the limitations of self-reported data, particularly when the socially desirable outcome is likely to
be known and salient.

Sustainability is a widely-recognized challenge for WASH interventions. At five months post-
intervention, Healthy Villages and Schools increased access to improved water sources and
improved sanitation facilities[26]. Notably, these improvements largely persisted to 3.6 years post-
intervention, as did the improvements in WASH institutions. Yet these improvements did not result
in any measurable effect on diarrhea or growth faltering. This highlights that it is crucial to measure
health outcomes directly and not assume that better inputs are sufficient to yield improvements.

This study has several limitations. First, the trial had incomplete adherence: 86% of villages in the
intervention group reported that they had implemented the community action plan to address
WASH challenges (e.g. by building new infrastructure) by the 3.6-year follow-up. However, this is
a realistic level of adherence for a government-implemented program. Indeed, given that many
study villages were conflict-affected, the take-up rate was substantial. Second, we have no
baseline measures. Although the randomized design means that such measures are not required
for unbiased estimates of treatment effects, there are theoretical challenges; for example, if
permanent migration out of study villages was affected by the intervention, then our estimates
may be biased. However, at 3.6 years post-intervention we were able to re-interview 88% of the
                                                                                                  13


households interviewed at 5 months post-intervention, suggesting that migration was relatively
rare in our study population. We also restricted households that were newly recruited at 3.6 years
to those who had lived in their current residence for at least four years. Third, the outcomes that
are self-reported may suffer from reactivity or social-desirability bias.

Our results reinforce calls for more ambitious attempts to improve WASH services to reduce
stunting and diarrhea, such as “transformative WASH.” [34] Proponents of transformative WASH
argue that some or all of the following may be necessary to produce significant health gains: high
community coverage of improved sanitation facilities; living environments free from animal feces;
continuous, convenient access to clean water; new approaches to behavior change; or new
technologies to deliver WASH services. [31] Others go further and argue for transformative
housing, with connections to water and sanitation networks. [12] These critiques are relevant in
our setting, given the multiple potential sources of contamination, the low quality of even
“improved sources”, and the high burden of disease. Business as usual is not enough.

Data sharing statement

Individual-level, de-identified data from this study and code to reproduce all results are publicly
available in the World Bank micro-data catalogue here:
https://reproducibility.worldbank.org/index.php/catalog/239.

Figure titles and legends
Fig 1. Trial Profile.
HH = household

Fig 2. Distribution of length-for-age Z-scores, intervention and control groups
Length-for-age Z-scores for children aged 0-5 years, in the intervention group (n=919) and the
control group (n=1223).

Supporting information
S1 Table. Randomization strata
S2 Table. Intervention effects on WASH institutions index and index sub-components
S3 Table. Intervention effects on all secondary outcomes, including index sub-components
S4 Table. Intervention effects on all primary outcomes, separately by province (pre-specified)
S5 Table. Intervention effects on all primary outcomes, province-by-intervention interaction
models
S6 Table. Intervention effects on diarrhea and length-for-age z score, separately by sex (pre-
specified)
S7 Table. Intervention effects on diarrhea and length-for-age z score, sex-by-intervention
interaction models
S8 Table. Variable definitions
S1 Text. Consort checklist
S2 Text. Protocol and pre-analysis plan, 5-month follow-up
S3 Text. Protocol and pre-analysis plan, 3.6 year follow-up
                                                                                                14



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1
                                                                                                                          17


Figures
Figure 1. Trial profile

                                                     403 villages identified by
                                                     intervention implementer
                                                                                            34 villages in Kasai province
                                                                                            excluded because they received
                                                                                            the intervention prior to

                                                   369 villages eligible, grouped
                                                          into 124 clusters
                                                                                            30 villages (3 clusters) in
                                                                                            North Kivu dropped due to

                                           339 villages in 121 clusters randomly
                                           assigned to intervention or control




                                  50 clusters randomly                      71 clusters randomly
                               assigned to the intervention                assigned to the control
                                          group                                     group
                                      (            )



 2 villages randomly dropped
 from largest cluster in in Kasai,                                                               3 villages randomly dropped
 due to intervention budget                                                                      from largest cluster in in Kasai,
 constraint                                                                                      due to intervention budget
                                                                                                 constraint
 1 village randomly dropped
 from largest cluster in in Kongo                                                                1 village randomly dropped
 Central, due to intervention                                                                    from largest cluster in in Kongo
 budget constraint                                                                               Central, due to intervention
                                                                                                 budget constraint
 1 village in Kasai was not able
 to be reached                                                                                   1 village in South Kivu did not
                                                                                                 exist
 1 village in Kasai did not exist




                                50 clusters                                          71 clusters
                               144 villages                                         185 villages
                   Four midline panel HHs per village =                 Four midline panel HHs per village =
                                   489                                                  644
                   Replacement HHs for midline HHs =                   Replacement HHs to midline HHs = 92
                                    87
                                                                         Six new randomly selected HHs per
                   Six new randomly selected HHs per                            village = 1,109 HHs*
                            village = 862 HHs*                            *In one village, only five new HHs
                   *In three villages, only five new HHs                          were interviewed
                             were interviewed
                                                                          Total = 1,845 HHs interviewed 3.5
                                                                                     18



Figure 2. Distribution of length-for-age Z-scores, intervention and control groups
                                                                                                19


Supporting Information

S1 Table. Randomization strata

                                 Total                     Control    Total
                       Villages- villages   Intervention   villages   clusters   Intervention Control
                       per-      in         villages in    in         in         clusters in  clusters in
Province     Stratum   cluster   stratum    stratum        stratum    stratum    stratum      stratum
Kongo
Central         1         1-2       15           8            7          12          6               6
                2         3-4       13           6            7           4          2               2
                3         5,7       12           7            5           2          1               1
Kasai           1         1-2       37          19           18          26          13              13
                2         3-5       39          21           18          11          6               5
                3        10,12      22          12           10           2          1               1
Kasai
Central         1         1-2      34            8           26         25           6               19
                2         3-4      34            8           26         10           2               8
                3         6-7      13            0           13          2           0               2
South Kivu      1         1-2      20            9           11         13           6               7
                2        4-8,10    74           39           35         12           6               6
                3        12,14     26           12           14          2           1               1
Total                              339          149          190        121          50              71
                                                                                                                                   20


S2 Table. Intervention effects on WASH institutions index and index sub-components


                                          Control                     Intervention                                      CI 95%
                                                                                                               Lower             Upper
 Outcomes                         n      Mean        SD           n        Mean        SD          ITT         Bound             Bound
 WASH institutions index         185      0.00      1.00        144         0.46      0.75        0.40          0.16             0.65
 Committee (y/n)                 185      0.70      0.46        144         0.97      0.16        0.21          0.10             0.32
 Committee mtg freq*              88      2.91      1.49        104         2.62      1.61        -0.29         -0.79            0.20
 WASH expenditures (CDF
 per month, IHS)                 130      2.12      4.07        140         3.28      4.58        1.14          0.07             2.20
 Track health (y/n)              185      0.69      0.46        144         0.84      0.37        0.16          0.07             0.25
 Track sanitation (y/n)          185      0.74      0.44        144         0.78      0.41        0.05          -0.06            0.15

ITT = intention-to-treat effect estimate. CDF = Congolese francs. IHS = inverse hyperbolic spline. Effects are estimated with
models that include controls for randomization blocks based on province and number of villages per cluster. There were 121
clusters in total. The WASH institutions index was calculated by rescaling each variable in the index (e.g., presence of WASH
committee) so that higher values imply better outcomes, then standardizing relative to the control group, following Kling et al.
Effects are in standard deviation units. The index values range from -2.35 to 2.12.
*Committee meeting frequency is coded 1-6, where 1=weekly, 2=Fortnightly, 3=Monthly, 4=Every 3 months, 5=Every 6 or more
months, 6=No regular schedule, based on needs
                                                                                                                                     21


S3 Table. Intervention effects on all secondary outcomes, including index sub-
components
                                                                  Control                    Intervention                       CI 95%
                                                                Prevalence/                  Prevalence/
 Outcomes                                                 n        Mean        SD      N        Mean         SD     ITT     Lower    Upper

 Improved water source                                   1845      43%                1437      74%                 0.24    0.12     0.36

 Improved sanitation                                     1843      14%                1437      34%                 0.18    0.10     0.25

 Water governance perception index                       1845      0.00       1.00    1438      0.22        0.88    0.19    0.04     0.34

 Committee selected fairly                               600       1.76       0.81    1119      1.82        0.76    0.06    -0.04    0.17

 Committee treats community fairly                       621       4.15       1.31    1158      4.07        1.31    -0.09   -0.27    0.09

 Committee manages money well                            635       3.25       1.12    721       3.31        1.14    0.05    -0.13    0.23

 Comm responds breakdown well                            972       3.69       1.18    1227      3.67        1.23    0.01    -0.13    0.15

 Confidence committee will solve reported issue          1009      3.10       1.05    1227      3.12        1.03    0.02    -0.13    0.17

 Satisfaction with water access (1-5)                    1845      2.76       1.49    1438      3.38        1.43    0.56    0.27     0.85



 Time spent collecting water (IHS)                       1845      4.17       2.07    1438      4.04        2.05    0.03    -0.20    0.27

 HHs pay for water (Dummy)                               1845      10%                1438      23%                 0.09    0.00     0.19

 Water use expenditure (weekly)                          137       153        217     303       254         351     114      -16     243

 Hygiene and behaviour index                             1845      0.00       1.00    1438      0.30        1.07    0.23    0.12     0.34

 Handwashing score (0-10)                                1845      2.79       2.22    1438      3.41        2.16    0.43    0.19     0.67

 Open defecation (%)                                     1843      32%                1437      27%                 -0.03   -0.08    0.01

 Self-reported handwashing with soap/ash (%)             1843      67%                1437      82%                 0.09    0.06     0.13

 Frequency of latrine cleaning over past 2 weeks         761       4.89       4.26    648       5.00        4.06    0.25    -0.32    0.82

 Water in pot is clean and covered (%)                   1669      57%                1273      57%                 0.02    -0.03    0.07

 Water treated for consumption, any method (%)           1669      3%                 1273       7%                 0.03    0.01     0.05



 Handwashing action                                      616       15%                489       17%                 0.00    -0.04    0.03

 Handwashing with soap/ash                               616       2%                 489        4%                 0.01    -0.01    0.03

 Water point has water                                   380       97%                266       85%                 -0.11   -0.18    -0.05

 WP FIB MPN/100mL                                        366      79.31       37.92   221      72.41        42.56   -9.46   -18.85   -0.06

 WP FIB log10 MPN/100mL                                  366       1.71       0.60    221       1.58        0.70    -0.17   -0.32    -0.02

 HH FIB MPN/100mL                                        1098     82.27       35.05   851      79.44        37.71   -3.87   -9.59    1.86

 HH FIB log10 MPN/100mL                                  1098      1.76       0.53    851       1.72        0.58    -0.06   -0.15    0.04



 Weight for age                                          1223     -1.17       1.16    919       -1.14       1.16    0.06    -0.04    0.15

 Weight for length                                       1224      0.14       1.07    918       0.22        1.03    0.10    -0.02    0.22

 Life satisfaction & self-esteem index                   1843      0.00       1.00    1435      0.03        0.98    0.01    -0.12    0.14

 Life satisfaction (WVS)                                 1843      4.87       3.20    1435      5.04        2.89    0.20    -0.10    0.49

 Feel I am person of worth (Rosenberg)                   1843      2.25       0.90    1435      2.19        0.90    -0.03   -0.13    0.07

 Feel that I have good qualities (Rosenberg)             1843      2.42       0.74    1435      2.36        0.75    -0.02   -0.10    0.05

 Inclined to feel I am a failure (Rosenberg)             1843      1.43       1.11    1435      1.49        1.05    -0.04   -0.16    0.08

 Able to do things as well as other people (Rosenberg)   1843      2.44       0.75    1435      2.40        0.76    0.01    -0.06    0.08

 Feel have not much to be proud of (Rosenberg)           1843      0.98       0.98    1435      0.99        0.92    -0.05   -0.14    0.04

 Take a positive attitude towards self (Rosenberg)       1843      2.35       0.78    1435      2.37        0.74    0.08    -0.01    0.17

 I am satisfied with myself (Rosenberg)                  1843      2.03       1.02    1435      2.12        0.96    0.16    0.07     0.26
                                                                                                                                         22


 Wish could have more respect for myself (Rosenberg)                           1843   0.42   0.60   1435   0.40   0.57   -0.07   -0.13   0.00

 Certainly feel useless at times (Rosenberg)                                   1843   1.33   1.10   1435   1.40   1.07   -0.03   -0.16   0.10

 At times think I am no good at all (Rosenberg)                                1843   1.32   1.09   1435   1.43   1.07   0.00    -0.12   0.12



 Psychological well-being index                                                1843   0.00   1.00   1435   0.05   0.99   0.06    -0.06   0.17

 Felt cheerful last 2 weeks (WHO)                                              1843   2.59   1.72   1435   2.64   1.64   0.05    -0.12   0.22

 Felt calm & relaxed last 2 weeks (WHO)                                        1843   2.62   1.68   1435   2.68   1.59   0.06    -0.11   0.22

 Felt active & vigorous last 2 weeks (WHO)                                     1843   2.57   1.64   1435   2.61   1.54   0.04    -0.13   0.21

 Woke up fresh & rested last 2 weeks (WHO)                                     1843   2.58   1.62   1435   2.56   1.53   0.02    -0.14   0.18

 Daily life filled with things that interest last 2 weeks (WHO)                1843   2.25   1.76   1435   2.30   1.70   0.12    -0.06   0.29

 Felt unable to control important things last month (Cohen)                    1843   2.95   1.26   1435   2.92   1.12   -0.06   -0.17   0.05

 Felt confident about ability to handle personal problems last month (Cohen)   1843   3.09   1.27   1435   3.05   1.17   0.02    -0.08   0.13

 Felt confident things were going your way last month (Cohen)                  1843   2.81   1.33   1435   2.89   1.25   0.10    -0.02   0.23

 Felt difficulties were piling up could not overcome them last month (Cohen)   1843   2.39   1.28   1435   2.56   1.20   0.10    -0.03   0.23



 School attendance (days past week)                                            299    3.21   2.72   226    2.74   2.72   -0.38   -0.82   0.07



ITT = intention-to-treat effect estimate; HH = household; FIB = fecal indicator bacteria; MPN = most probable number; IHS =
inverse hyperbolic spline; WHO = World Health Organization; WVS = World Values Survey. Effects are estimated with models that
include controls for randomization blocks based on province and number of villages per cluster. There were 121 clusters in total.
The WASH governance perceptions index and the hygiene and behavior index were calculated by rescaling each variable in the
index (e.g., satisfaction with water access) so that higher values imply better outcomes, then standardizing relative to the control
group, following Kling et al. Effects are in standard deviation units.
                                                                                                                                             23


S4 Table. Intervention effects on all primary outcomes, by province (pre-specified)

                                                     Control                      Intervention                              CI 95%

 Outcomes                  Province        n     Prevalence/Mean   SD     n     Prevalence/Mean   SD      ITT    Lower Bound    Upper Bound

 Diarrhea prevalence       Kongo Central   146        17%                 163        10%                 -0.07      -0.15            0.00

                           Kasai           599        40%                 679        40%                 0.00       -0.09            0.09

                           Kasai Central   781        49%                 196        59%                 0.10       0.00             0.19

                           South Kivu      784        41%                 724        37%                 -0.05      -0.10            0.01



 Length-for-age Z-score    Kongo Central   96         -1.59        1.32   93         -1.75        1.67   -0.18      -0.47            0.11

                           Kasai           319        -2.05        1.60   328        -1.86        1.60   0.20       -0.05            0.44

                           Kasai Central   409        -2.12        1.71   103        -2.58        1.49   -0.42      -0.80            -0.04

                           South Kivu      399        -2.49        1.48   395        -2.50        1.50   0.02       -0.16            0.19



 WASH institutions index   Kongo Central   18         0.27         0.66   20         0.59         0.57   0.31       -0.06            0.68

                           Kasai           43         -0.48        1.10   48         0.21         0.75   0.70       0.21             1.19

                           Kasai Central   65         -0.18        0.85   16         0.28         0.61   0.35       0.03             0.68

                           South Kivu      59         0.46         0.96   60         0.67         0.78   0.23       -0.25            0.71

ITT = intention-to-treat effect estimate. Effects are estimated with models that include controls for randomization blocks based on
province and number of villages per cluster. There were 121 clusters in total. The WASH institutions index was calculated by rescaling
each variable in the index (e.g., presence of WASH committee) so that higher values imply better outcomes, then standardizing
relative to the control group, following Kling et al. Effects are in standard deviation units.
                                                                                                                          24


S5 Table. Intervention effects on all primary outcomes, province-by-intervention
interaction models

                                        (1)           (2)           (3)          (4)           (5)          (6)
                                        WASH          WASH          Diarrhea -   Diarrhea -    Height for   Height for
                                        Intitutions   Intitutions   Simple       Interaction   Age -        Age -
                                        Index -       Index -                                  Simple       Interaction
                                        Simple        Interaction


Intervention                            0.404***      0.308*        -0.010       -0.070*       -0.014       -0.172
                                        (0.125)       (0.167)       (0.022)      (0.036)       (0.070)      (0.134)


Kasai Province # cluster_strata=2       -0.644**      -0.024        0.267***     0.003         -0.085       0.090
                                        (0.251)       (0.256)       (0.050)      (0.044)       (0.200)      (0.149)


Kasai Province # cluster_strata=3       -0.432*       0.196         0.232***     -0.031        0.222        0.396***
                                        (0.221)       (0.315)       (0.078)      (0.077)       (0.172)      (0.091)

Kasai Central Province #
cluster_strata=2                        -0.263        0.185         0.372***     -0.024        -0.347       -0.005
                                        (0.201)       (0.199)       (0.059)      (0.055)       (0.261)      (0.222)

Kasai Central Province #
cluster_strata=3                        -0.866**      -0.430        0.335***     -0.036        -0.143       0.106
                                        (0.410)       (0.411)       (0.063)      (0.059)       (0.168)      (0.140)


Sud-Kivu Province # cluster_strata=2    -0.064        0.042         0.273***     0.035         -0.729***    0.096
                                        (0.231)       (0.237)       (0.041)      (0.032)       (0.161)      (0.141)


Sud-Kivu Province # cluster_strata=3    0.670**       0.763***      0.268***     0.030         -0.240       0.586***
                                        (0.262)       (0.223)       (0.042)      (0.028)       (0.164)      (0.142)


Kasai Province                                        -0.835***                  0.226***                   -0.359*
                                                      (0.314)                    (0.054)                    (0.212)


Kasai Central Province                                -0.488*                    0.339***                   -0.323
                                                      (0.272)                    (0.050)                    (0.223)


Sud-Kivu Province                                     -0.065                     0.224***                   -0.912***
                                                      (0.293)                    (0.050)                    (0.227)


Intervention # Kasai Province                         0.391                      0.069                      0.365**
                                                      (0.293)                    (0.058)                    (0.182)


Intervention # Kasai Central Province                 0.044                      0.168***                   -0.242
                                                      (0.230)                    (0.059)                    (0.226)
                                                                                                                                         25



 Intervention # Sud-Kivu Province                              -0.076                        0.022                        0.184
                                                               (0.286)                       (0.044)                      (0.158)


 Child's sex                                                                  0.010          0.010          0.134**       0.135**
                                                                              (0.014)        (0.014)        (0.062)       (0.062)


 Child's age (years)                                                          -0.043***      -0.043***      -0.233***     -0.234***
                                                                              (0.004)        (0.004)        (0.033)       (0.033)


 Constant                                       0.272          0.324          0.235***       0.268***       -1.323***     -1.248***
                                                (0.168)        (0.214)        (0.039)        (0.044)        (0.182)       (0.204)


 Observations                                   329            329            4072           4072           2142          2142
 Wald_F                                                        0.790                         3.169                        3.022
 Wald_p                                                        0.502                         0.027                        0.032

Coefficients and standard errors from linear models of the primary outcomes on intervention group, fixed effects for randomization
strata, fixed effects for province, and intervention-by-province interaction terms. Standard errors are clustered by cluster (group of
villages). There were 121 clusters in total. The WASH institutions index was calculated by rescaling each variable in the index (e.g.,
presence of WASH committee) so that higher values imply better outcomes, then standardizing relative to the control group, following
Kling et al. Effects are in standard deviation units. The Wald F is a test statistic for the null hypothesis that all of the interaction term
coefficients are zero. * p<.1, ** p<.05, *** p<.01"
                                                                                                                                 26


S6 Table. Intervention effects on diarrhea and length-for-age z score, separately by sex
(pre-specified)
                                          Control                         Intervention                                CI 95%
                                         Prevalence                         Prevalence
                                             /                                  /                               Lower      Upper
 Outcomes         Province       n         Mean         SD         n          Mean         SD          ITT      Bound      Bound
 Diarrhea         Female      1151      43%                     880        38%                      -0.01       -0.06     0.04
                  Male        1159      41%                     882        38%                      0.00        -0.06     0.05

 Length for       Female
 age                          605       -2.08         1.59      475        -2.19         1.64       -0.07       -0.24     0.10
                  Male        618       -2.28         1.61      444        -2.22         1.53       0.06        -0.14     0.26

ITT = intention-to-treat effect estimate. Effects are estimated with models that include controls for randomization blocks based on
province and number of villages per cluster. There were 121 clusters in total. The WASH institutions index was calculated by
rescaling each variable in the index (e.g., presence of WASH committee) so that higher values imply better outcomes, then
standardizing relative to the control group, following Kling et al. Effects are in standard deviation units.
                                                                                                                                         27


S7 Table. Intervention effects on diarrhea and length-for-age z score, sex-by-intervention
interaction models
                                                           (1)           (2)             (3)           (4)
                                                           Diarrhea -    Diarrhea -      Height for    Height for
                                                           Simple        Interaction     Age -         Age -
                                                                                         Simple        Interaction
 Treatment                                                 -0.010        -0.004          -0.014        0.071
                                                           (0.022)       (0.027)         (0.070)       (0.098)


 Child's sex                                               0.010         0.014           0.134**       0.206**
                                                           (0.014)       (0.018)         (0.062)       (0.084)


 Child's age (years)                                       -0.043***     -0.043***       -0.233***     -0.233***
                                                           (0.004)       (0.004)         (0.033)       (0.033)


 Kasai Province # cluster_strata=2                         0.267***      0.267***        -0.085        -0.089
                                                           (0.050)       (0.050)         (0.200)       (0.199)


 Kasai Province # cluster_strata=3                         0.232***      0.232***        0.222         0.213
                                                           (0.078)       (0.078)         (0.172)       (0.174)


 Kasai Central Province # cluster_strata=2                 0.372***      0.372***        -0.347        -0.351
                                                           (0.059)       (0.058)         (0.261)       (0.260)


 Kasai Central Province # cluster_strata=3                 0.335***      0.335***        -0.143        -0.150
                                                           (0.063)       (0.063)         (0.168)       (0.167)


 Sud-Kivu Province # cluster_strata=2                      0.273***      0.273***        -0.729***     -0.737***
                                                           (0.041)       (0.041)         (0.161)       (0.159)


 Sud-Kivu Province # cluster_strata=3                      0.268***      0.268***        -0.240        -0.242
                                                           (0.042)       (0.042)         (0.164)       (0.163)


 Treatment # Female                                                      -0.011                        -0.168
                                                                         (0.028)                       (0.122)


 Constant                                                  0.235***      0.233***        -1.323***     -1.354***
                                                           (0.039)       (0.040)         (0.182)       (0.185)
 Observations                                              4072          4072            2142          2142
 Wald_F                                                                  0.159                         1.883
 Wald_p                                                                  0.691                         0.173
Coefficients and standard errors from linear models of the primary outcomes on intervention group, fixed effects for randomization
strata, fixed effects for child sex, and intervention-by-sex interaction terms. Standard errors are clustered by cluster (group of
villages). There were 121 clusters in total. The WASH institutions index was calculated by rescaling each variable in the index (e.g.,
presence of WASH committee) so that higher values imply better outcomes, then standardizing relative to the control group, following
Kling et al. Effects are in standard deviation units. The Wald F is a test statistic for the null hypothesis that all of the interaction term
coefficients are zero. * p<.1, ** p<.05, *** p<.01"
                                                                                                       28


S8 Table. Variable definitions
        Descriptions of primary and secondary outcomes, including index
                                 subcomponents

 Category        Outcomes                                  Definition

 Primary         Diarrhea                                  Prevalence of diarrhea in last 7 days of
 Outcome                                                   children under 5 (caregiver reported):
                                                           1. Yes to ‘diarrhea’ , or
                                                           2. Yes to ‘three or more stools” AND
                                                           ‘watery or soft stool’, or
                                                           3. Yes to blood in the stool

 Primary         Length for age                            Length for age z score for children under
 Outcome                                                   5.
                                                           The sample does not include
                                                           observations with implausible z-scores.

 Primary         WASH institutions index                   The index is built from: (1) Presence of
 Outcome                                                   water committee; (2) Frequency of
                                                           meeting; (3) Average amount spent per
                                                           month for water activities excluding
                                                           maintenance (inverse hyperbolic sine); (4)
                                                           Tracks health conditions; (5) Tracks
                                                           hygiene and sanitation

 Subcomponent    Presence of water committee               1 if the village has a water committee
                                                           0 Otherwise
 Subcomponent    Frequency of meeting                      Frequency of committee meeting. The
                                                           variable ranges from 1 to 6:
                                                           1         Weekly
                                                           2         Fortnightly
                                                           3         Monthly
                                                           4         Every 3 months
                                                           5         Every 6 or more months
                                                           6         No regular schedule, based on
                                                           needs
 Subcomponent    Average amount spent per month for            Average amount spent per month for
                 water activities excluding maintenance.   water activities excluding maintenance.
                                                           An inverse hyperbolic sine transformation
                                                           has been applied to the variable.
 Subcomponent    Tracks health conditions                  1 if village keeps track of community
                                                           health conditions
                                                           0 Otherwise
 Subcomponent    Tracks hygiene and sanitation             1 if village keeps track of WASH practices
                                                           0 Otherwise
                                                                                           29


Secondary      Water governance perception index   Water governance perception index is
Outcome                                            constructed based on the following
                                                   variables: fairness of selection of water
                                                   governance entity; perception of fair
                                                   treatment; confidence in managing money
                                                   of committee; confidence in committee
                                                   response to breakdowns; confidence in
                                                   committee management; Satisfaction with
                                                   water access
Subcomponent   Committee selected fairly           The extent to which the process of
                                                   choosing committee members was fair
                                                   The answer choices are:
                                                   Not fair at all;
                                                   Somewhat fair;
                                                   Fair;
                                                   Fully fair
Subcomponent   Committee treats community fairly   The extent to which the water committee
                                                   treats you fairly
                                                   The answer choices are:
                                                   Very unfair
                                                   Somewhat unfair
                                                   Neither fair nor unfair
                                                   Somewhat fair
                                                   Very fair
Subcomponent   Committee manages money well        How well the water committee manages
                                                   money
                                                   The answer choices are the following:

                                                   Very badly
                                                   Badly
                                                   Neither bad nor good
                                                   Good
                                                   Very good
Subcomponent   Comm responds breakdown well        How well the water committee responds
                                                   to breakdowns
                                                   The answer choices are the following:

                                                   Very badly
                                                   Badly
                                                   Neither bad nor good
                                                   Good
                                                   Very good
Subcomponent   Confidence committee will solve     Level of confidence that water committee
               reported issue                      will solve issue respondent brings up
                                                   The answer choices are the following:

                                                   Not confident at all
                                                   Not very confident
                                                                                                 30


                                                      Somewhat confident
                                                      Very confident
Subcomponent   Satisfaction with water access (1-5)   Level of satisfaction of respondent with
                                                      your access to water
                                                      The answer choices are the following:

                                                      Not satisfied at all
                                                      Not satisfied
                                                      Indifferent
                                                      Satisfied
                                                      Very satisfied

Secondary      Improved water source                  1 if Household’s Primary source of
Outcome                                               drinking water is improved source (JMP
                                                      definition) and 0 otherwise.

                                                          ●    Improved main drinking source
                                                               includes Piped into dwelling,
                                                               Piped into plot, Piped/public tap,
                                                               Tube well or borehole, Protected
                                                               dug well, Protected spring,
                                                               Rainwater, Tanker truck.

                                                          ●    Unimproved main drinking source
                                                               includes Unprotected dug well,
                                                               Unprotected spring, Surface
                                                               water, No other main source

Secondary      Time spent collecting water (IHS)       Each household was asked to list
Outcome                                               household members who participated on
                                                      previous day, and the number of trips
                                                      undertaken by the household. For each
                                                      trip, the collector was identified and the
                                                      time spent for the round trip was
                                                      collected. For each household, we sum
                                                      time spent for each trip in minutes to get
                                                      the total time spent collecting water per
                                                      household. To estimate treatment effects,
                                                      an inverse hyperbolic sine transformation
                                                      was applied due to the large number of
                                                      zeroes.

Secondary      HHs pay for water (Dummy)              1 if household pay for water
Outcome                                               0 Otherwise

Secondary      Water use expenditure (weekly)         Estimated household’s weekly
Outcome                                               expenditure for water use (in CDF,
                                                      Congolese Franc)
                                                                                        31


Secondary      Improved sanitation           Household uses an improved latrine (JMP
Outcome                                      definition)
                                                 ●       Improved sanitation includes
                                                      options such as Flush / Pour
                                                      Flush: to Piped Sewer System,
                                                      Flush / Pour Flush: to Septic
                                                      Tank, Flush / Pour Flush: to Pit
                                                      Latrine, Ventilated Improved Pit
                                                      Latrine (VIP), Pit Latrine with
                                                      Slab, Composting Latrine.

                                                 ●   Unimproved sanitation includes
                                                     Flush / Pour Flush: to Elsewhere,
                                                     Flush / Pour Flush: to Don’t Know
                                                     Where, Pit Latrine without Slab /
                                                     Open Pit, Bucket Latrine,
                                                     Hanging Toilet, No Facilities
                                                     (Bush, Open Field, River), Other
                                                     (specify)

Secondary      Hygiene and behaviour index   Self-reports of: Knowledge: Caregiver
Outcome                                      knows how and when to wash hands;
                                             what causes diarrhea. Sanitation
                                             practices: cleanliness of household area
                                             and latrine (presence of flies and fecal
                                             matter); open defecation; observed
                                             indicators of toilet use –worn pathway,
                                             presence of water; improvements to
                                             latrine; disposes of child feces safely
                                             (JMP definition). Water storage practices:
                                             has a clean pot for water that is covered.
Subcomponent   Handwashing score (0-10)      Self-report of: Knowledge: Caregiver
                                             knows how and when to wash hands. The
                                             variables considered are the following:
                                             count 1 if respondent mentioned
                                             unprompted that they wash hands with
                                             soap/ash in critical juncture X (= 0 if they
                                             say no or they say it prompted). The
                                             counts are then added up to create a
                                             score.
                                             The considered junctures are the
                                             following: After toilet; after washing baby’s
                                             bottom/changing; after eating; before
                                             preparing food; before eating; before
                                             feeding/breastfeeding baby; before or
                                             after handling children; after taking care
                                             of pets or farm animals; after
                                             coughing/sneezing; after coming back
                                             from the fields.
                                                                                                         32


Subcomponent   Open defecation (%)                       1 if no defecation facility used and 0
                                                         otherwise
Subcomponent   Self-reported handwashing with            1 if respondent washed their hands with
               soap/ash (%)                              soap/ash at least once since previous day
                                                         0 Otherwise
Subcomponent   Frequency of latrine cleaning over past   Number of times the latrine has been
               2 weeks                                   cleaned in the past 2 weeks
Subcomponent   Water pot is clean and covered (%)        1 if the pot has clean water and is
                                                         covered
                                                         0 Otherwise.
                                                         This indicator is measured via actual
                                                         observations
Subcomponent   Water treated for consumption, any        1 if drinking water stored in household is
               method (%)                                treated with any product/method for safe
                                                         consumption
                                                         0 otherwise

Secondary      Life satisfaction & self-esteem index     Summary index of 11 questions
Outcome                                                  The 11 questions include the (1) life
                                                         satisfaction question as defined by the
                                                         World Values Survey and (2) the 10
                                                         questions as defined in Rosenberg's Self-
                                                         Esteem Scale.
Subcomponent   Life satisfaction (WVS)                   All things considered, on a scale of 1 to
                                                         10, how satisfied are you with your life as
                                                         a whole?

                                                         1 means completely dissatisfied
                                                         10 means completely satisfied
Subcomponent   Feel I am person of worth (Rosenberg)     I feel I am a person of worth, at least on
                                                         an equal plane with others.

                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   Feel that I have good qualities           I feel that I have a number of good
               (Rosenberg)                               qualities.

                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   Inclined to feel I am a failure           All in all, I am inclined to feel that I am a
               (Rosenberg)                               failure.

                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
                                                                                                      33


Subcomponent   Able to do things as well as oth people   I am able to do things as well as most
               (Rosenberg)                               other people.

                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   Feel have not much to be proud of         I feel I do not have much to be proud of.
               (Rosenberg)
                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   Take a positive attitude towards self     I take a positive attitude toward myself.
               (Rosenberg)
                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   I am satisfied with myself (Rosenberg)    On the whole, I am satisfied with myself.

                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   Wish could have more respect for          I wish I could have more respect for
               myself (Rosenberg)                        myself.

                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   Certainly feel useless at times           I certainly feel useless at times.
               (Rosenberg)
                                                         Tell me to what extent you: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about you.
Subcomponent   At times think I am no good at all        At times I think I am no good at all.
               (Rosenberg)
                                                         To what extent do respondents: Strongly
                                                         agree, Agree, Disagree, or Strongly
                                                         disagree with this statement about them

Secondary      Psychological well-being index            Summary index of 9 questions on well-
Outcome                                                  being in last 2 weeks and stress in last 4
                                                         weeks.

                                                         The questions used here belong to two
                                                         different sets of questions. The first set is
                                                         the 5 WHO questions on well-being, and
                                                         the second set is the Cohen stress scale
                                                         4 questions.
                                                                                                       34


                                                             Each of the five WHO statements on well-
                                                             being refers to how respondents have
                                                             been feeling over the last two weeks. The
                                                             answer choices are the following: At no
                                                             time; Some of the time; Less than half of
                                                             the time; More than half of the time; Most
                                                             of the time; All of the time.

                                                             Questions in the Cohen stress scale, ask
                                                             the respondent about their feelings and
                                                             thoughts during THE LAST MONTH. The
                                                             answer choices are the following: Never;
                                                             Almost never; Sometimes; Fairly often;
                                                             Very often.
Subcomponent   Felt cheerful last 2 weeks (WHO)              Over the last two weeks, I have felt
                                                             cheerful and in good spirits.

                                                             The answer choices are the following: At
                                                             no time; Some of the time; Less than half
                                                             of the time; More than half of the time;
                                                             Most of the time; All of the time.
Subcomponent   Felt calm & relaxed last 2 weeks              Over the last two weeks, I have felt calm
               (WHO)                                         and relaxed.

                                                             The answer choices are the following: At
                                                             no time; Some of the time; Less than half
                                                             of the time; More than half of the time;
                                                             Most of the time; All of the time.
Subcomponent   Felt active & vigorous last 2 weeks           Over the last two weeks, I have felt active
               (WHO)                                         and vigorous.

                                                             The answer choices are the following: At
                                                             no time; Some of the time; Less than half
                                                             of the time; More than half of the time;
                                                             Most of the time; All of the time.
Subcomponent   Woke up fresh & rested last 2 weeks           Over the last two weeks, I woke up
               (WHO)                                         feeling fresh and rested.

                                                             The answer choices are the following: At
                                                             no time; Some of the time; Less than half
                                                             of the time; More than half of the time;
                                                             Most of the time; All of the time.
Subcomponent   Daily life filled with things that interest   Over the last two weeks, my daily life has
               last 2 weeks (WHO)                            been filled with things that interest me.

                                                             The answer choices are the following: At
                                                             no time; Some of the time; Less than half
                                                                                                      35


                                                            of the time; More than half of the time;
                                                            Most of the time; All of the time.
Subcomponent   Felt unable to control important things      In the last month, how often have you felt
               last month (Cohen)                           that you were unable to control the
                                                            important things in your life?

                                                            The answer choices are the following:
                                                            Never; Almost never; Sometimes; Fairly
                                                            often; Very often
Subcomponent   Felt confident about ability to handle       In the last month, how often have you felt
               personal problems last month (Cohen)         confident about your ability to handle your
                                                            personal problems?

                                                            The answer choices are the following:
                                                            Never; Almost never; Sometimes; Fairly
                                                            often; Very often
Subcomponent   Felt confident things were going your         In the last month, how often have you felt
               way last month (Cohen)                       confident that things were going your
                                                            way?

                                                             The answer choices are the following:
                                                            Never; Almost never; Sometimes; Fairly
                                                            often; Very often
Subcomponent   Felt difficulties were piling up could not    In the last month, how often have you felt
               overcome them last month (Cohen)             difficulties were piling up so high that you
                                                            could not overcome them?

                                                            The answer choices are the following:
                                                            Never; Almost never; Sometimes; Fairly
                                                            often; Very often

Secondary      Handwashing action                           Share of adult household members who
Outcome                                                     were observed washing their hands at
                                                            any juncture, measured via structured
                                                            observations.

                                                            The considered junctures are the
                                                            following:
                                                            Before obtaining water from a wide-
                                                            mouthed storage container;
                                                            Before cutting or preparing food;
                                                            Before serving food;
                                                            Before eating;
                                                            Before feeding child under 5;
                                                            Before breastfeeding child;
                                                            After defecation;
                                                            After toileting;
                                                            After cleaning child post- toileting
                                                                                    36



Secondary   Handwashing with soap/ash   Share of adult household members who
Outcome                                 were observed washing their hands with
                                        soap/ash at any juncture, measured via
                                        structured observations.

                                        The considered junctures are the
                                        following:
                                        Before obtaining water from a wide-
                                        mouthed storage container;
                                        Before cutting or preparing food;
                                        Before serving food;
                                        Before eating;
                                        Before feeding child under 5;
                                        Before breastfeeding child;
                                        After defecation;
                                        After toileting;
                                        After cleaning child post- toileting

Secondary   School attendance           Number of days child aged 6 to 18 years
Outcome                                 old attended school in past week, based
                                        on responses to “How many days has this
                                        child attended school in the past week?”
                                        Children who were not enrolled in school
                                        were coded as zero.
Secondary   Water point has water       1 if water point provides water
Outcome                                 0 Otherwise
                                        (Locked water points during survey are
                                        not considered)

Secondary   WP Coliforms MPN/100mL      Water quality at point of collection (village
Outcome                                 water source) is Most Probable Number
                                        (MPN) in 100 mL as defined for
                                        Aquagenx CBT EC+TC MPN water
                                        quality testing kits and follow WHO
                                        standards. For nondetects, we substitute
                                        half the lower detection limit.

Secondary   HH Coliforms MPN/100mL      Water quality at point of use (Drinking
Outcome                                 water stored in the household) is Most
                                        Probable Number (MPN) in 100 mL as
                                        defined for Aquagenx CBT EC+TC MPN
                                        water quality testing kits and follows WHO
                                        standards. For nondetects, we substitute
                                        half the lower detection limit.

Secondary   Weight for age              Weight for age z score for children under
Outcome                                 5.
                                                                          37



                                The sample does not include
                                observations with implausible z-scores.




Secondary   Weight for length   Weight for length z score for children
Outcome                         under 5.

                                The sample does not include
                                observations with implausible z-scores.
                                                                                                38


S1 Text. CONSORT 2010 checklist of information to include
when reporting a randomized trial*
                                                                                  Reported in
                     Item                                                          Section/
Section/Topic         No Checklist item                                           Paragraph
Title and abstract
                     1a   Identification as a randomized trial in the title     Title
                     1b   Structured summary of trial design, methods,          Abstract
                          results, and conclusions (for specific guidance see
                          CONSORT for abstracts)

Introduction
Background and       2a   Scientific background and explanation of              Introduction
objectives                rationale
                     2b   Specific objectives or hypotheses                     Last
                                                                                paragraph,
                                                                                Introduction
Methods
Trial design         3a   Description of trial design (such as parallel,        Study design
                          factorial) including allocation ratio
                     3b   Important changes to methods after trial              NA
                          commencement (such as eligibility criteria), with
                          reasons
Participants         4a   Eligibility criteria for participants                 Study design,
                                                                                9th paragraph
                     4b   Settings and locations where the data were            Study design,
                          collected                                             5th paragraph
Interventions         5   The interventions for each group with sufficient      Procedures
                          details to allow replication, including how and
                          when they were actually administered
Outcomes             6a   Completely defined pre-specified primary and          Outcomes
                          secondary outcome measures, including how
                          and when they were assessed
                     6b   Any changes to trial outcomes after the trial         NA
                          commenced, with reasons
Sample size          7a   How sample size was determined                        Statistical
                                                                                analysis
                     7b   When applicable, explanation of any interim           NA
                          analyses and stopping guidelines
Randomization:
  Sequence           8a   Method used to generate the random allocation         Randomization
    generation            sequence                                              and masking
                                                                                               39


                      8b    Type of randomization; details of any restriction   Randomization
                            (such as blocking and block size)                   and masking
  Allocation          9     Mechanism used to implement the random              Randomization
      concealment           allocation sequence (such as sequentially           and masking
      mechanism             numbered containers), describing any steps
                            taken to conceal the sequence until
                            interventions were assigned
  Implementation      10    Who generated the random allocation sequence,       Randomization
                            who enrolled participants, and who assigned         and masking
                            participants to interventions
Blinding              11a   If done, who was blinded after assignment to        NA
                            interventions (for example, participants, care
                            providers, those assessing outcomes) and how
                      11b   If relevant, description of the similarity of       NA
                            interventions
Statistical           12a   Statistical methods used to compare groups for      Statistical
methods                     primary and secondary outcomes                      analysis
                      12b   Methods for additional analyses, such as            Statistical
                            subgroup analyses and adjusted analyses             analysis
Results
Participant flow (a   13a   For each group, the numbers of participants who     Study design
diagram is                  were randomly assigned, received intended
strongly                    treatment, and were analyzed for the primary
recommended)                outcome
                      13b   For each group, losses and exclusions after         Study design
                            randomization, together with reasons
Recruitment           14a   Dates defining the periods of recruitment and       Results
                            follow-up
                      14b   Why the trial ended or was stopped                  NA
Baseline data          15   A table showing baseline demographic and            Table 2
                            clinical characteristics for each group
Numbers               16    For each group, number of participants              Tables 3-4
analysed                    (denominator) included in each analysis and
                            whether the analysis was by original assigned
                            groups
Outcomes and          17a   For each primary and secondary outcome,             Results,
estimation                  results for each group, and the estimated effect    Tables 3-4
                            size and its precision (such as 95% confidence
                            interval)
                      17b   For binary outcomes, presentation of both           Tables 3-4
                            absolute and relative effect sizes is
                            recommended
                                                                                                                    40


 Ancillary analyses         18     Results of any other analyses performed,                       Results; Supp
                                   including subgroup analyses and adjusted                       Info
                                   analyses, distinguishing pre-specified from
                                   exploratory
 Harms                      19     All important harms or unintended effects in                   NA
                                   each group (for specific guidance see CONSORT for harms)
 Discussion
 Limitations                20     Trial limitations, addressing sources of potential             Discussion, 2nd
                                   bias, imprecision, and, if relevant, multiplicity of           to last
                                   analyses                                                       paragraph
 Generalizability           21     Generalizability (external validity, applicability) of         Discussion
                                   the trial findings
 Interpretation             22     Interpretation consistent with results, balancing              Discussion
                                   benefits and harms, and considering other
                                   relevant evidence
 Other information
 Registration               23     Registration number and name of trial registry                 Study design
 Protocol                   24     Where the full trial protocol can be accessed, if              Study design
                                   available
 Funding                    25     Sources of funding and other support (such as                  Abstract
                                   supply of drugs), role of funders

*We strongly recommend reading this statement in conjunction with the CONSORT 2010 Explanation and
Elaboration for important clarifications on all the items. If relevant, we also recommend reading CONSORT
extensions for cluster randomized trials, non-inferiority and equivalence trials, non-pharmacological treatments,
herbal interventions, and pragmatic trials. Additional extensions are forthcoming: for those and for up-to-date
references relevant to this checklist, see www.consort-statement.org.