Phase 1 Birth: Parental and Birth data were collected at the first recruitment in 1969-73. All married women who were not pregnant in the study area were recruited and followed up until they became pregnant and gave birth. 10,670 live births were recruited (rural 6,260, urban 4,410), representing a broad range of socio-economic status. Around 20% of infants also had a sibling recruited. Data were collected at birth in relation to a) parent’s socio-economic status (e.g. education and occupation of both parents; condition of house; access to water and sanitation; household size etc), b) details of the pregnancy (e.g. antenatal care; obstetric history),
Phase 2 Infancy: details of the infant at birth (e.g. weight and length; head and chest circumference) and d) history of consanguinity. Length/height was measured at 1, 2, 3, 6, 9, and 12 months and weight was measured at 1,2 and 3 months, and at 6-8 years and 10-15 years. Further information collected included breast feeding and morbidity patterns during the first year; IQ at 6-8 years was assessed and blood pressure at 10-15 years was measured.
Phase 3 and 4 Childhood & Adolescence: Follow-up studies at two time periods in childhood (6 to 8 years of age) and adolescence (10 to 15 years of age) focusing on physical and mental growth were carried out. During the childhood study period, 5541 children were observed with a maximum of two follow up measurements per child. About 2672 children from the original cohort were followed up on a yearly basis during the adolescent study period with a minimum of single observation per child to a maximum of six observations per child.
Phase 5 Adult follow-up 1: For the follow-up in young adulthood at the age of 26-32 years (1998–2002), the main objective was to study glucose tolerance, insulin resistance and insulin secretion and a range of cardiovascular risk factors (body composition, blood pressure and plasma lipid concentrations) in relation to parental size, neonatal size and childhood growth. This study was funded by the British Heart Foundation.
Phase 6 Adult follow-up 2: A subgroup of the VBC participants (n=1080) were invited to participate in a research protocol that aimed to study ophthalmic disease in relation to early growth. This was funded by grants from London School of Hygiene and Tropical Medicine, Public Health Foundation of India and Christian Medical College and Hospital, Vellore
Phase 7 Adult follow-up 3: Currently participants are being recruited under IndEcho study, funded by the British Heart Foundation.
