PFIN Technical Note 85-12 A BENEFIT-COST ANIALYSIS OF NUTRITIONAL INTERVETIONS FOR ANEMIA REDUCTION by Henry M. Levin Stanford University July 1985 Population, Health and Nutrition Department World Bank The World Bank does not accept responsibility for the views expressed herein which are those of the author(s) and should not be attributed to the World Bank or to its affiliated org7anizations. The findings, interpretations, and conclusions are the results of research supported by the Bank; they do not necessarily represent official policy of the Bank. The designations employed, Lhe presentation of material, and any maps used in this document are solely for the convenience of the reader and do not imply the expression of any opinion whatsoever on the part of the World Bank or its affiliates concerning the legal status of any country, territory, city, area, or of its authorities, or concerning the delimitations of its boundaries, or national affiliation. TABLE OF CONTENTS PAGE ABSTRACT . . . . . . . . . . . . . . . . .. SUMMARY AND CONCLUSIONS ..........................ii I INTRODUCTION ....................... ...... 1 II PREVALENCE AND TREATMENT OF ANEMIA . 4 III BENEFITS OF ANEMIA REDUCTION . . .......... 17 IV COSTS OF INTERVENTIONS . . . . . . . . . . 38 V CALCULATING COSTS ....................... ..... 43 VI CALCULATING BENEFITS . .... . . . . . 59 VII CALCULATING BENEFIT-COST RATIOS. . ....... 70 BIBLIOGRAPHY . . . . . . . . . . . . . . . 86 LIST OF TABLES TAB LE PAGE ONE POPULATIONS AT RISK: ESTIMATED PERCENTAGE 6 WITH HEMOGLOBIN CONCENTRATION BELOW THE NORM FOR NON-ANEMIC SUBJECTS rWO LRON INTERVENTLONS AND CHAN&GES IN HE4OGLOBIN 18 LEVELS T'HREE HEMOGLOBIN LEVELS AND MEASURES OF WORK OUTPUT 27 FOUR ESTIMATED ANNUAL COST FOR DELIVERING 'MEDICAL 55 SUPPLEIMELNTS Tro REDUCE ANEMIA (BASED ON SERVICE. FOR I ,000 PERSONS) FIVE ESTIMATED IMPACT OF IRON INTERVENTLONS ON 63 WORK OUTPUT S t.K ESTIMATED BENEFITS PER CAPITA OF ANEMIA 72 INTERVENTIONS IN INDONES IA SEVENI ESTIMATED BENEFITS PER CAPITA OF ANEMIA 73 INTERVENTIONS IN KENYA EIGHT ESTIMATED BENEFITS PER CAPITA OF ANEMIA 74 INTERVENTIONS IN MEXICO NIINE ESTIMATED COSTS OF ANEMIA INTERVENTIONS 75 PER CAPITA TELNI PER CAPITA BENEFITS AND COSTS OF FORTIFICATION 79 ELEVEN PER CAP ITA BENEFITS AND COSTS OF SUPPLEMENTATION 80 PHN Technical Note 85-12 A BE1NEFITt-COST ANALYSIS OF NUTRITIONAL INTERVENTIONS FOR ANEMIA REDUCTION A B S T R A C T Iron-deficiency anemia is one of the most prevalent nutritional disorders in both the industrialized and less-developed countries. The purpose of this paper is to evaluate potential interventions for reducing anemia with a benefit-cost analysis. The study begins with a discussion of the origins and prevalence of anemia and proceeds to some of thie consequences of anemia on work capacity, work output, learning, and other outcomes. Specific estimates are made of the effects of reducing anemia on work output. Both medicinal supplementation and fortification of food with iron are considered as interventions. Each intervention is evaluated for the costs of specific strategies in less-developed societies, with particular emphasis on cost estimates for Indonesia, Kenya, and Mexico. Estimates of benefits are calculated for the value of additional work output in labor-surplus societies as well as assessments of other benefits. The results of the cost and benefit analysis are used to construct benefit-cost ratios for evaluating the investment potential of anemia interventions. Under a wide range of assumptions, the benefit-cost ratios are found to be substantially greater than one. This is especially true of dietary fortification where the benefit-cost ratios were found to be between 7 and 70 for the three illustrative countries. But even dietary supplementation was found to show a range of benefits to cost of from 4 to 38 for the most reasonable set of assumptions. The study concludes that benefit-cost ratios of nutritional interventions to reduce anemia appear to be large, and field trials should be carried out in specific settings to see if the overall findings of this study are supported in particular cases, * * ** *** * * *** * Prepared by: Henry M. Levin, Consultant to the World Bank Stanford University July 1985 SUMMARY AND CONCLUSIONS Although anemia is a serious nutritional problem around the world, it is especially severe in the tropics where regional studies have commonly found more than half of the population to be anemic. Populations that are especially at risk are infants, children, and women and especially pregnant or lactating women. Nutritional. interventions focus on increasing iron intake (and folate where indicated) as well as increasing the dietary intake of foods or agents that vwill increase iron absorption. Especially important in increasing iron absorption from existing sources is the addition of ascorbic acid to the diet and foods that are rich in heme sources of iron such as meat, poultry, and fish. Such interventions can take the form of medicinal supplementation through orally taken or injected iron compounds or dietary fortification through the addition of the appropriate compounds to food vehicles found in the normal diet. The latter is generally to be preferred because it has a lower distribution cost and does not require changes in behavior in order to improve Hb. Such interventions have been shown to raise Hb levels dramatically, especially among those with severe anemia. Thera are- many studies on the. effects of H:b on humar. behavior, but the evidence seems to be most substantial in the. area of work capacity and work output. Work capacity refers to various physiological indicators of the capability for doing work such as maximum oxygen uptake and the heart rate and production of lactates for any particular level of work - 11 - effort. Experimental studies have shown that when Hb of anemic sub- jects is raised through nutritional interventions, the maximum oxygen uptake rises; and heart rate and lactates associated with a given work effort decline. Quantitative estimates are provided in the report. Summaries of a large number of studies that relate Hb and changes in Hb to work output show similar conclusions. Among a wide range of national settings and measures of work, Lt appears that a 1 percent rise in Hb is associated with between a I and 2 percent increase in work output. This finding is remarkably robust among different investigations. Other studies show the relation of Hb to intellectual growth and school achievement, morbidity, infection, and so on. Given an understanding of the nature of interventions and the benefits that might result from them, the report attempts to estimate the monetary values of the costs and benefits. Costs are estimated for medicinal supplementation and for dietary fortification. In both cases, the costs are estimated by first stipulating the resources that would be required for the interventions such as personnel, facilities, transportation, supplies, and iron compounds or ascorbic acid. The costs of these resources are estimated under different assumptions regarding the markets for them in different settings. In addition, the cost estimates take account of additional caloric requirements of workers with higher work output as a result of anemia interventions. Benefits are estimated by assessing the value of additional work output for agricultural workers in societies characterized by labor surpluses. They are predicated on the assumption that the additional output of a worker is equal to about half of the average wage of that - iii - worker in such a context. Benefits are also estimated for the non-labor market effects of reductions in anemia. The costs and benefits are calculated for agricultural workers in three countries: Indonesia, Kenya, and Mexico. The estimated monetary value of benefits exceeds costs by substantial margins for all three countries for both supplementation and fortification. Under the most "reasonable" sets of assumptions, the benefit-cost ratios for fortification are estimated to be about 7 for Indonesia, 43 for Kenya, and 71 for Mexico. For supplementation, the comparable benefit-cost ratios are 6, 34, and 56. These high benefits relative to costs seem to hold under a wide variety of different assumptions regarding the calculations. The overall conclusion is that nutrition interventions for reducing anemia appear to represent social investments that are highly productive and that ought to be considered seriously by the Bank. In addition, it would be useful to carry out field trials of interventions in which costs and benefits were estimated directly in order to see if the global results found in this study are supported by specific interventions at particular sites. - iv - A BENEFIT-COST ANALYSIS OF NUTRITIONAL INTERVENTIONS FOR. ANEMIA REDUCTION L. INTRODUCTION One f t.he imost prevalent riutritional disorders .n both industrialized and less-deve IDoped countries (LDC' s) is iron-deficiency anemia (Baker and DeMaeyer L979: 388-92; Charlton and Bothwell 1982; Fleming 1982; Masawe 1981). Anemia refers to a condition in which the hemoglobin concentration in the blood is considered to be be low some normal value for a given populat ion. Although anemia may be caused by other factors such as disease or blood loss, the most common cause is a deficiency of iron (Charlton and BOathwell 1982 : 310-16). Such iron deficiency is typicaLLy a result of an inadequat.e intake of absorbable iron, relative to the needs of the body for forming hemoglobin and meeting other iron needs. The hemoglobin level is particularly important, since it provides the oxygen-transport mechanism for the body. At low hemoglobin levels, the b lood is restricted in its capacity to carry oxygen to the celLs, limiting the ability of the body to produce energy and meet other functional needs. From a health-related perspective, the anemic person feels weak, listless, and may be more susceptible to infection. Work capacity is also impaired, and anemic chiLdren perform less welL in school. Many of these behavioral outcomes of anemia have been summarized in reviews on the subject (e.g. PoLlitt, V'iteri, Saco-Pollitt, and Leibel 1982; Pollitt and Leibel 1976; Read 1975; Scrimshaw 1984). The purpose of£ this study is to evaluate potential interventions for reducing iron-deficiency anemia in LDC' s from the perspective or an 2 inves tment in human resources as evaluated by a cost-benefit analysis (Sorkin 1976: 33-9). All investments have a cost which can be defined as the value of the resources ucilized for the intervention (Levin 1983). The benefits are equivalent to the value of the outcomes that are produced by the intervention. In the case ot interventions to reduce iron-deficiency aneMia, the costs derive from the dietary iron supplements or fortification and the system for delivering them to insure that they are consumed by che appropriate populations. Potential benefits are associated with the improved feeling of well-being of the populations, improved fetal and child growth, Lower morbidity and mortality, higher productivity both inside and outside of the workplace, more enjoyment of lei~sure, and more effective learning among students. The case for using a cost-benefit analysis for evaluating programs for alLeviating iron-deficiency anemia is straightforward. LDC's are characterized by a large number cf challenges such as unemployment, health probleias, nutritional deficiencies, poor education, inadequate housing and transportation. The potential responses to these problems are also many. Investments in health, nutrition, education, housing, transportation, water resources, and agricultural and industrial development all represent potential paths for improving the welfare of the population. But, it is likely that some investments will be relatively more productive in their impacts than o thers for any aiven resource out lay. The purpose of cost-benefit analysis is to ascertain if the benefits of a particular s trategy exceed its costs and by ho; much. In this way one can compare the cost-benefit status of one alternacive with others and can 3 choose those alternatives which are likely to maximize the benefits to the society relative to their costs. In its ideal form, cost-benefit analysis provides a guideline for ctioosing investment priorities when resources are Limnited relative to the needs that they must address (Mishan 1976). Ideally, this exploration would proceed from a case studv or series of such studies in which interventions were undertaken under different sets of representative conditions. Precise measures would be available for all of the factors that were pertinent, and one need only place them into a bene fit-cost framework to provide the necessary result.s. Unfortunately, no such case studies exisc that provide systematic data for alL of the pertinent relations. However, a large variety of studies exist that can be used to "construct" a picture of the magnitudes of benefits and costs of anemia interventions. The purpose of this study is to use available data to establish the overall parameters of benefits and costs for strategies to reduce nutritional anemia. A major emnphasis will be on building a methodology tthat can be applied to new data as they arise or to specific field trials. Lii constructing this framework, a variety of assumptions wilL be used to establish linkages where more precise data are lacking. The attempt will be to make the methodology and assumptions transparent so that other assumptions can be imposed in order to see if they would modify the conc lu s ions. This study should not be viewed as a substitute for one based upon f ield trials in specific settings, but only as an overall benefit-cost guide to anemia interventions. The remainder o f this report will be organized in the following way. Section II will discuss the prevalence and treatment of anemia. Section III wiLl develop the potential benefits of anemia reduction, and Section IV 4 wi L L present the costs of interventions to reduce iron-deficiency anemia. Seccions V and VI will develop specific calculations for coscs and benefits raspectively. The final section will integrate these results into a benefit-cosr frainework. LI . PREVALENCE AND TREATMENT OF ANEMIA In this section we will present information on the prevalence of anemia and its treatment. Diagnosis of anemia is usualLy made on the basis of an evaluation of the hemoglobin content of the b.lood. Hemoglobin is a substance of iron (heme) and protein (globin) found in the red corpuscles Of ciie blood that carries oxygea fromn the Lungs to the tissues and some of che carbon dioxide froa the tissues to the lungs. Each molecule of hemoglobi,n can carry four molecules of oxygen. In a non-anemic person, elach liter of blood contains between 110 and 160 grams of hemoglobin. Reinotglobin accounts for about two-thirds of the 3..5 grams of iron in the healthy adulc male. The standard test for anemia is to assess the concentration of hemoglobin, which is usually evaluared in grams per deciliter of blood (g/dl). An alternative measure is hematocrit which requires only a minute amount of blood and can be done in a small clinic or office. The hematocrit is about equal to the hemoglobin (Hb) concentration multCiplied by 3, however it is a less reliable means of diagnosing anemia (DalLman 1982: 67). Although groups like the World Health Organizacion (WHO) have established general criteria for determining if a person is anemic, the an o ra" l a I e v of hemoglobin, at sea-le vel, w i 1 L d i F f e r f r o m 5 person-to-person and population-to-population. For eKL=-c&, WHO (1968) defined the following levels of hemoglobin concentration in g/dl below whiich anemia is likely to be present: children 6 months to 6 year.s, 11; children 6 to 14 years, 12; adult males, 13; adult females, non-pregnant L2; and adult- emales, pregnant,ll. However, these are conv.idered to be zeneral indicators of anemia rather than precise criteria. Likewise, iron requirelnents also differ among individuals and groups. Daily requirements o f iron that mus t be ab sorbed to maintain homeostasis are estimated to range from .7 mg for infarnts and .9 mg 'or men to about 3 mg for women in the second half of pregnancy (Baker and DeMaeyer 1979:375). One mne thod of ascertaining if an individual is anemic is to establish an initial hemoglobin or hematocrit level followed by dietary supplement with irorn and a subsequent measurement of hemnogliAin or hematocrit. Those persons whose hemoglobin or hematocrit levels rise as a response to supplementation are considered to have been anemic. The larger the response, the more serious the anemia. For any population it is possible to relate different initial Levels of hemoglobin concentrations with response rates to determine a "cutoff" value for Hb that would predict that persons be low that level were anemic (Leibel, Pollitt, Kim and Viteri 1982). Cook and Finch (1979) have shown that alternative laboratory measurements of iron status may be more useful than Rb concentrations among some populations, particular those with mild iron deficiencies, and that in field t.rials it may be desirable to use multiple measures. Anemia is a serious nutritional problem around the world, bur especially in the tropics (Fleming 1977 & 1982; Slasawe 198'1; Woodruff 6 TABLE ONE POPULATIONS AT RISK: ESTIMATED PERCENTAGE WITH HEIOGLOBIN CONCENTRATION BELOW TiE NORM FOR NON-ANEAMIC SUBJECTS Countrv Date A&e Sex Urban/Rural % Anemic 3angLadesh 19762 adult F-pregnant Urban 66a 3urma 19761 adulc F-pregnant Urban 82a Surina 19722 adult F-pregnant Urban ,-4ia Burma 19724 pre-school M/F 3-27c Fiji (Indian) 19704 adult 80C North India 19681 adult F-pregnant Rural 80a A;orth India 19734 children M/F 9Qb adult M/ F 48g/ 84c South India 1968/19731 adult F-pregnant Mainly Urban 57.4a Souch India 19752 children M/F aural 76c adult M2 Rural 56c adult F Rural SIc India 19752 adult F-pregnant Urban/Rural 88a Indonesia 19802 adult F-Pregnant Rural 37a (East Java) F 30c :ndonesia (West 19732 adult F-pregant Rural 65a & Central Java, Bali) Jatnica L9794 pre-school M/F 76c Kenya 19573 adult M/F Rural 32.3e Latin America 19711 adult F-pregnant Mixed 26.5a Latin America 19714 adult M1 Mixed 4c .Maur i t ius 19603 pre-school / F 5 Od Malaysia 19642 adult F-pregnant Urban 75a :'e:ico 19681 adult F-pregnant Rural 26.6a .;eoai 19772 adult F-pregnant Urban 35a Pakistan 19702 adult F-pregnant Urban 73a 7 T BLE L: (continued) C5uncrv Date Age Sex Urban/Rural % Anemic * .ilippines 19712 adult F-pregnant Urban 63a : i1ippines 29762 adult F-pregnant Urban -2a ;I'?ppines 19764 pre-school M/F 4c adult M' 7c adult F 37: -o Land 19681 adult F-pregnant Urban 21.3a z6uch 'iZrica 19763 adulc 14 44. 3c "'a tal) adult F 33.lc r,apre 19722 adult F-pregnant Uirban Indian 205 Urban Ma lay 215 'Jrban Chinese Gb iri Lanka 19572 adult F-pregnant Rural 5Oa 3,.i Lanka 29744 adult F Oc adult 14g .-rzania 19733 adult M4/F RU raL 37.3f .ai Land 19802 adult F-pregnant Urban BOa I.Ban;kok) _ aiLand (Ubal) l9712 adult F-pregnant Rural 48a .;iailand 19794 pre-school 14/F 45c adult M 35c adult F 45c Thailand 19802 pre-school M/F L5c children M/F 33C 15-49 M1 1Sc 15-49 F 18c over 49 14 34c over 49 F Si c :ricerion: a) Hb