General population-based cohort
The Andhra Pradesh Children and Parent Study (APCAPS) is a large prospective, intergenerational cohort study in Southern India that began with the long-term follow-up of the Hyderabad Nutrition Trial (1987-1990). It is situated in 29 villages near the city of Hyderabad in Ranga Reddy district, Andhra Pradesh.
The Hyderabad Nutrition Trial evaluated the Integrated Child Development Services (ICDS) scheme, a national community outreach program, which provides a daily food supplement to pregnant women and children under 6 years of age. The trial used a controlled stepped wedge design, recruiting pregnant women from 29 villages (15 intervention with program; 14 controls awaiting implementation) and followed them through to childbirth.
In 2003-5, trial households were retraced and surveyed: families with at least one child born during the trial period and still alive in 2003-05 became the APCAPS prospective cohort (1815 families, 2601 index children). At this time, a first wave (W1) of data collection was carried out on index children and their mothers. The index children were then re-examined as young adults (aged 18-23 years) in 2009-10 (the second wave, W2) and then again in 2010-12 (the third wave, W3) when their siblings and parents were also examined. A socio-demographic household survey of all residents in all 29 villages was completed between 2012 and 2014.