Parker 2008.

Methods	Study design: randomized controlled trial Sampling frame: households in southwest or eastside Detroit with children age 7 to 11 with persistent asthma Sampling method: questionnaires mailed to all caregivers of children age 7 to 11 who attended 1 of 44 elementary schools in neighborhoods; for households with more than 1 eligible child, the child with the most severe symptoms was chosen. Participants participating in baseline assessment were randomly assigned to intervention or control group Collection method: asthma screening questionnaire, measurements of lung function Description of the community coalition: partnership with Detroit Community‐Academic Urban Research Center (URC); community‐based participatory research (CBPR) with steering committee composed of representatives of 8 community‐based organizations, a health service agency, a state agency, an academic institution, and community members
Participants	Communities: eastside and southwest Detroit, MI Country: USA Ages included in assessment: children age 7 to 11 (n = 298) Reasons provided for selection of intervention community: high rates of African American and Latino residents; statistics demonstrating high rates of asthma hospitalization, high rates of poverty, pre‐existing efforts to address health concerns, and pre‐existing relationships Intervention community (population size): 165,000 Comparison community (population size): same
Interventions	Name of intervention: Community Action Against Asthma (CAAS) Theory: Empowerment and Social Cognitive Theory Aim: to improve children’s asthma‐related health by reducing household environmental triggers for asthma through activities delivered by community health workers (CHWs) Description of costs and resources: not provided Components of the intervention: community health worker home visits (> 9/y). CHWs provided tailored information, strategies, methods, and materials to reduce environmental triggers, as well as referral to medical treatment and/or other social services (e.g. food bank) (intervention group: n = 162; control group: n = 166) Start date: 2000 Duration: 12 months
Outcomes	Outcomes and measures: lung function (daily nadir forced expiratory volume, daily nadir peak flow), asthma symptoms (cough that will not go away, coughing with exercise), unscheduled medical visits, use of asthma controller medications Time points: 1‐year follow‐up
Notes	Funder: National Institute for Environmental Health Sciences and the US Environmental Protection Agency Funding source: government
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random number generator used for randomization
Allocation concealment (selection bias)	Unclear risk	Not described
Baseline outcome measurement similar	High risk	Unscheduled medical care and uncontrolled symptoms higher in intervention group at baseline; P values not provided
Baseline characteristics similar	Low risk	Intervention and control groups showed no significant differences with regard to baseline characteristics
Blinding of outcome assessment (detection bias) All outcomes	High risk	No blinding reported
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	25% attrition rates did not differ between intervention and control
Blinding of participants and personnel (performance bias) All outcomes	High risk	No blinding performed
Protection against contamination	Unclear risk	Cases and controls lived in close geographic proximity and attended the same schools
Selective reporting (reporting bias)	Low risk	Main outcomes reported