Yes / Background: There is an absence of evidence about interventions to prevent or treat obesity in early childhood and in South Asian populations, in whom risk is higher. Objectives: To study patterns and the aetiology of childhood obesity in a multiethnic population and develop a prevention intervention. Design: A cohort of pregnant women and their infants was recruited. Measures to compare growth and identify targets for obesity prevention, sensitive to ethnic differences, were collected. A feasibility randomised controlled trial (RCT) was undertaken. Setting: Bradford, UK. Participants: A total of 1735 mothers, 933 of whom were of South Asian origin. Intervention: A feasibility trial of a group-based intervention aimed at overweight women, delivered ante- and postnatally, targeting key modifiable lifestyle behaviours to reduce infant obesity. Main outcome measures: The feasibility and acceptability of the pilot intervention. Data sources: Routine NHS data and additional bespoke research data. Review methods: A systematic review of diet and physical activity interventions to prevent or treat obesity in South Asian children and adults. / National Institute for Health Research