Thompson 2008.

Methods	Study design: cluster‐randomized trial Sampling frame: Participants were recruited through 3 approaches: (1) participants in previous research study in same area; (2) additional households identified in 16 communities with high rates of Hispanic agricultural workers, and (3) households in labor camps Sampling method: All previous participants and households from labor camps were contacted; additional households in 16 communities were randomly sampled Collection method: in‐person interview, urine samples of farmworkers and children age 2 to 6, environmental sampling (house and vehicle dust) Description of the community coalition: Community Planning Group, consisting of 18 individuals from 16 diverse organizations, including farmworkers, growers, health department, regulatory agencies, farmworker clinics, advocates, and local media
Participants	Communities: 16 communities and 8 labor camps in Yakima Valley, Washington Country: USA Ages included in assessment: adult farmworkers (n = 213) and their children age 2 to 6 (n = 211) Reasons provided for selection of intervention community: Agricultural communities in Yakima Valley of Washington State have a high percentage of Hispanic agricultural workers, many of whom work with organophosphates. 24 communities were randomly assigned to intervention or control condition Intervention community (population size): 300 to 11,000 Comparison community (population size): 300 to 11,000
Interventions	Name of intervention: Para Niños Saludables Theory: not reported Aim: to reduce pesticide exposure among farmworkers and their children via a community‐based intervention trial Description of costs and resources: not reported Components of the intervention: Comprehensive intervention included activities at community (health fairs, festivals), organizational (schools and preschools, churches, English language and citizenship classes, orchards, farms), small group (lay health promotoras, home health parties), and individual (promotoras conducted individual outreach at community sites) levels. Main activities included information provision and education, distribution of educational materials, and media advocacy Start date: 1999 Duration: 2 years
Outcomes	Outcomes and measures: farmworkers’ and children’s urinary metabolite levels of pesticides (organophosphates)  Time points: baseline (year 1) and follow‐up (year 4)
Notes	No information provided regarding intervention and control community characteristics. Urinary metabolite concentrations were increased in both intervention and control communities Funder: National Institute for Environmental Health Sciences and US Environmental Protection Agency Funding source: government
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	High risk	Allocation not concealed
Baseline outcome measurement similar	Low risk	No P values reported, but for urinary metabolites baseline measurements appear to be similar
Baseline characteristics similar	Low risk	Study authors report no differences between intervention and control communities
Blinding of outcome assessment (detection bias) All outcomes	High risk	Blinding not reported
Incomplete outcome data (attrition bias) All outcomes	Low risk	High response rates, independent samples
Blinding of participants and personnel (performance bias) All outcomes	High risk	Blinding not reported
Protection against contamination	High risk	Contamination was monitored by including questions in a final survey regarding awareness of and participation in intervention activities; estimated to be ˜20%
Selective reporting (reporting bias)	Low risk	Questionnaire described in detail