Bowen 2009.

Methods	Cluster RCT where religious organisations in Seattle were the unit of randomisation. Called the Eating for a Healthy Life project.
Participants	Members of religious organisations (cluster RCT where 40 religious organisations were randomised ‐ 2175 individuals). 100 households were drawn at random from each religious organisation (RO) list and further samples as required to complete the cohort. Individuals had to be active members of the RO, at least 18 years, English speakers, resident in the area for the next 12 months, had phone number and address, and had agreed to be contacted for follow‐up. The sample size calculation of 20 pairs of ROs assumed an intra‐class correlation of 0.015 for the primary outcome fruit and fibre questionnaire based on previous data. Data is analysed at the level of the individual using regression analyses which allowed for adjustment of random RO‐level variation in addition to variation from individual respondents. The denominator used in this review is the RO.The mean age of the participants was 54 (15.9) years (range 18‐100) with approximately equal numbers in the 30‐50 year and 50‐79 year age groups. 86% of the participants were female.
Interventions	Intervention package of self‐help books and motivational messages and social interactions designed to change dietary behaviours (lowering fat and increasing F&V consumption). Materials were based on social learning theory and trans‐theoretical models of behavioural change. The dietary intervention package was implemented for 9 months in each intervention RO. A healthy eating coordinator was assigned to each RO to help deliver the intervention. Intervention components included a volunteer advisory board, interpersonal support, dietary change mailings, social activities, healthy eating sessions and print advertisements. The spacing out of individual components was determined by the advisory boards for each RO appropriate for each RO climate. The intervention was targeted at the primary food preparer in each household, but all intervention components were made available to the entire RO membership. The intervention period was 9 months with follow‐up at 12 months. The control ROs received the intervention after 12 months.
Outcomes	Primary outcomes were fat and F&V related behaviours using the Fat and Fibre Behaviour (FFB) Questionnaire. In 30% of the sample fat % energy intake, fruit and vegetable servings/day and dietary fibre (g/1000Kcal) were measured.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Stratified randomisation of religious organisations by denomination, size, baseline response rate, percentage of families and education level.
Allocation concealment (selection bias)	Unclear risk	No details
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No details. Cluster randomisation avoids contamination.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details
Incomplete outcome data (attrition bias) All outcomes	Low risk	Losses to follow‐up were similar for each group (9.4% of the intervention group and 11% of the control group were lost to follow‐up at 12 months).
Selective reporting (reporting bias)	Unclear risk	All expected outcomes reported.
Other bias	Unclear risk	Insufficient information to judge.