Methods and issues in conducting a community-based environmental randomized trial

The environment is suspected to play an important role in the prevalence and severity of asthma in inner-city children. This paper describes the implementation and baseline data of an inner-city community-based participatory research clinical trial designed to test the effectiveness of a pollutant and allergen control strategy on children's asthma morbidity. Participants were 100 elementary-school-aged children with asthma, graduates of a school-based asthma education program in East Baltimore. The intervention for half of the randomly assigned families consisted of environmental control education, allergen-proof encasements, pest extermination, and a HEPA air cleaner at the beginning of the study. Controls received the same at the end of the study. Participants visited a clinic for questionnaires, allergy skin testing, spirometry, and blood sample at baseline and 12 months. Home environments, NO₂, O₃, airborne particulates, and allergens were evaluated at baseline and at 6 and 12 months. Asthma morbidity and adherence was assessed quarterly. Collaboration with the community proved very beneficial in creating a study design and procedures acceptable to an inner-city community.