The Indian Government has endorsed a policy, in line with World Health Organization recommendations [15
], of providing routine iron supplementation to all children aged 6-60 months, and all pregnant and lactating women [5
]. By conducting both a targeted study in two districts of rural Karnataka and also using data from a nationally representative survey, we have found a marked difference between anaemia control policy and iron supplement receipt in the field. We have also identified considerable disparities that are partly mediated by socio-economic and health care factors.
Private providers, rather than government health care workers, are the major source of supplements for children. Possible reasons for this may include, firstly, a lack of availability of appropriate supplements within the government system: inadequate supply of supplements in rural Indian PHCs has been previously observed [18
], and government supplied liquid preparations suitable for children may be particularly difficult to access [19
]. Iron preparations appropriate for young children are more expensive than iron tablets in retail pharmacies in India [20
]. Secondly, government health workers and managers may be insufficiently educated about the importance of iron supplementation for prevention of anaemia in young children, and hence may not routinely provide this therapy [21
]. Thirdly, wealthier families may be more likely to seek optimal health outcomes through private providers [22
]. The unexpected finding in the Karnataka Study of an inverse association between children's receipt of iron supplementation and indicators of apparently good primary health care (receiving a full course of vaccinations and visits to the Anganwadi centre), together with the very low rate of distribution from government sources, raises the possibility that families who exclusively use government services are unable to receive iron supplements for their child through that system.
Data from both our field study and the NFHS-3 identify clear links between maternal anaemia control measures and delivery of iron to children. This may be due to improved awareness of anaemia and the value of iron in mothers, or to superior knowledge, attitudes and practices regarding anaemia prophylaxis in health workers caring for both mothers and their children. We have previously reported that children's haemoglobin concentrations in this population are chiefly associated with their iron status and their mother's haemoglobin [2
]. Thus, controlling maternal anaemia may prevent anaemia in children as well as improve the health of the mother. Iron supplementation programmes for pregnant [23
] and non-pregnant women [24
] have been successfully implemented in several settings worldwide, including in India [25
], and these programmes could be expanded with potential benefits for children as well as their mothers.
There are important differences between the methodology of the Karnataka Study and the NFHS-3. The two studies evaluated different outcomes: NFHS-3 asked whether children were currently receiving iron; the Karnataka Study asked whether children had ever received iron supplements. This may partly explain the lower national prevalence of receipt of iron identified on the NFHS-3: assuming all children received the nationally recommended 100 days of supplementation annually, and supplementation was evenly distributed across a year, 27% of children should have been receiving iron in the NFHS-3. However, the NFHS-3 data also indicated overall performance of services was poorer nationally than in the Karnataka Study. For example, whereas the Karnataka Study showed that 85.7% of children had ever visited an Anganwadi centre, NFHS-3 data shows that only 20.2% of children had visited a centre in the previous 3 months; this difference suggests heterogeneous access to ICDS services nationally that may explain the disparate findings in association between attendance at Anganwadi centres and receipt of iron between the two studies. Unlike the NFHS-3 data, the Karnataka study identified the source of iron received by children and thus was able to specifically evaluate government distribution. Although lower receipt of iron by children of Muslim families, as noted in the Karnataka Study, was not borne out nationally, this was identified among pregnant women from Muslim families in the national dataset. Finally, the Karnataka Study was prospectively designed with specific elements in the questionnaire to obtain a better understanding of the receipt of iron in rural India; the NFHS-3 dataset was used to perform a post-hoc analysis to understand iron receipt nationally.
Very few other published studies have reported receipt iron in the field by children in India. A study of 487 pregnant women in Andhra Pradesh identified receipt of iron by only 19%, and only 1% among children [7
]. The Micronutrient Taskforce reviewed national nutritional anaemia control programmes in 1996 and identified limitations, including "poor compliance, irregular supplies, (and) low education/counseling" [26
]. Thus, our study provides one of few comprehensive evaluations of iron supplementation both nationally, and in detail in a representative rural population.
The results of our study should be interpreted within the context of its strengths and limitations. This study analysed cross-sectional rather than longitudinal data, thus we are able to report only associations between variables, rather than definite cause and effect. Since the Karnataka Study sample size was relatively small, we sought to improve the external generalisability by also evaluating national (NFHS-3) data and making comparisons. Beyond variables measured in this study, there are likely to be multiple other factors that interact to affect the efficacy of anaemia control policies, concerning distribution and supply chains of iron supplements, performance of the health system as a whole, affordability of supplements, and acceptability of iron formulations to families.
Further research, including qualitative studies, are required to understand the gap between national anaemia control policy and practice in the field, and for disparities in receipt of iron supplements. Specifically, additional research is required to understand why receipt of iron was suboptimal in a setting where other vertical programmes (such as vaccination and Vitamin A distribution) function relatively well, as noted in the Karnataka Study. Such information may help to either specifically improve the iron supplementation programme or offer potential opportunities for synergy with these other programmes. Secondly, a study of the supply chain required for the provision of iron supplementation: from raw materials, manufacture, and distribution to the PHC, may help understand reasons for inadequate receipt of supplements that we did not address in this study. This could help programme managers plan for and procure sufficient stock of iron supplements for distribution through public systems. Thirdly, understanding the knowledge, attitudes and practices of government health workers and managers would help clarify how these factors affect implementation of anaemia control measures [27
]. This information would help policymakers direct their management and training messages to improve iron supplementation through the government health system. Finally, research directed at understanding the likely acceptability of liquid iron formulations by children and their mothers in the field could be undertaken to address adherence to supplements, if or when they are made available.
Our finding, both locally and nationally, that children belonging to poorer families are less likely to receive iron (despite a higher burden of anaemia in poorer children [2
]), is an example of the 'inverse care law': the poorest with greatest need have least access to valuable interventions [28
]. Based on our results, improving the receipt of iron supplementation among all, but especially the poorest families, could potentially be achieved through education of health workers responsible for providing iron during pregnancy, in the post partum, and to children. Additionally, other primary health services offer an opportunity to introduce iron supplementation, for example, integrated delivery with 9 and 18 month vaccinations or with Vitamin A supplements [29
]. Once women have experienced health benefits from iron, they may be more committed to continuing iron supplementation themselves [30
] and may also be more likely to seek iron supplementation for their children, as suggested by our data. However, beyond these strategies, emphasis must also be given to further developing longer-term strategies to eliminate anaemia including; development of effective alternatives to iron supplementation, such as home fortification by microencapsulated micronutrients [31
], iron fortification of staple foods, condiments and complementary foods [32
], and dietary diversification.