To describe the rationale, development and implementation of the quantitative component of evaluation of a multi-setting, multi-strategy, community-based childhood obesity prevention project (the eat well be active (ewba) Community Programs) and the challenges associated with this process and some potential solutions.

ewba has a quasi-experimental design with intervention and comparison communities. Baseline data were collected in 2006 and post-intervention measures will be taken from a non-matched cohort in 2009. Schoolchildren aged 10–12 years were chosen as one litmus group for evaluation purposes.

Thirty-nine primary schools in two metropolitan and two rural communities in South Australia.

A total of 1732 10–12-year-old school students completed a nutrition and/or a physical activity questionnaire and 1637 had anthropometric measures taken; 983 parents, 286 teachers, thirty-six principals, twenty-six canteen and thirteen out-of-school-hours care (OSHC) workers completed Program-specific questionnaires developed for each of these target groups.

The overall child response rate for the study was 49 %. Sixty-five per cent, 43 %, 90 %, 90 % and 68 % of parent, teachers, principals, canteen and OSHC workers respectively, completed and returned questionnaires. A number of practical, logistical and methodological challenges were experienced when undertaking this data collection.

Learnings from the process of quantitative baseline data collection for the ewba Community Programs can provide insights for other researchers planning similar studies with similar methods, particularly those evaluating multi-strategy programmes across multiple settings.