Rationale for a follow-up study focusing on economic productivity

Past studies of nutrition, human capital formation, and economic productivity have been limited by the fact that biomedical researchers and economists work largely in isolation, with loss of complementarity. Biomedical researchers are faulted for not adequately addressing bias and measurement issues and for naive analyses and interpretation of results, whereas economists are criticized for using simplistic nutrition and physiological measures and for relying on statistical methods rather than experimental designs. To avoid these problems, a multidisciplinary team of biomedical investigators and economists undertook a follow-up study in 2002-04 of a cohort of young men and women, who participated as young children in a randomized community trial of nutrition supplementation carried out from 1969-77 Previous studies, particularly the original trial and a 1988-89 follow- up, are described to provide an overview of the data available for linkage with the 2002-04 follow-up. Key results from these earlier studies are reviewed but judged inconclusive because the data used were collected when many subjects were still growing and developing physically, in school, unmarried, and/or not yet settled into occupations. The subjects were 26 to 41 years of age in 2003, permitting a more complete assessment of human capital and economic productivity. The experimental design of the 1969-77 original study, 35 years of follow-up, use of robust methods of data collection, and the participation of a multidisciplinary team will likely lead to the most comprehensive assessment to date of the importance of nutrition for economic productivity.