Cohort profile: the consortium of health-orientated research in transitioning societies

In 2005, plans were made for a series of papers on maternal and child undernutrition for publication in The Lancet. The second paper of the series aimed to describe the long-term consequences of maternal and child undernutrition for health and human capital. The focal person for this article "Cesar Victora from the Federal University in Pelotas, Brazil" decided to bring together available long-term data from low- and middle-income countries. He identified the five largest prospective birth cohort studies from these regions, all of which had at least 15 years of follow-up and an initial sample size of 2000 or more newborns. The principal investigators were approached, and all agreed to join the writing team. The five studies included the 1982 Pelotas (Brazil) Birth Cohort Study, the Institute of Nutrition of Central America and Panama Nutrition Trial Cohort (INTC; Guatemala), the New Delhi Birth Cohort (India), the Cebu Longitudinal Health and Nutrition Survey cohort (CLHNS; Philippines) and the Birth-to-Twenty (Bt20; Soweto-Johannesburg, South Africa) cohort. All the studies were population-based and started recruitment during gestation or at delivery; they have long follow-up periods; their study populations experienced high rates of maternal and/or child undernutrition, and all are currently undergoing rapid demographic, nutritional and epidemiological transitions. The experience of working together on the original paper, which was published in 2008, was highly positive. This motivated Cesar Victora, on behalf of the principal investigators, to apply for a research grant from the Wellcome Trust aimed at establishing a long-lasting collaborative network among the five cohorts. With funding, the group named the Consortium of Health-Orientated Research in Transitioning Societies (COHORTS), was formed and a logo created.