Community Trial

Community trials, also called community intervention studies, are (mostly preventive) experimental studies with whole communities (such as cities or states) as experimental units; that is, interventions are assigned to all members in each of a number of communities. These are to be distinguished from field trials where interventions are assigned to healthy individuals in a community and from clinical trials in which interventions are assigned to patients in a clinical setting. Except for the experimental unit, the conduct of controlled community trials follow the same procedures as controlled clinical trials, including the requirement of informed consent of the communities meeting the eligibility criteria (e.g., consent being given by city mayors or state governors), randomization to treatment and control groups, and follow-up and measurement of endpoints. ...