Methodologic advances and ongoing challenges in designing community-based health promotion programs.

Community intervention trials continue to attract researchers as potential ways to achieve widespread, long-term change in health behaviors. The first generations of community studies were somewhat unsophisticated in design and analysis, and their promise may have been overstated. As design and analysis issues were better defined, as secular trends caught up with the behaviors that researchers were trying to change, or as other unknown variables affected community studies, small effects of interventions were observed in community trials. Discussions were held in professional meetings and reported in the literature: Should community trials be discontinued? In general, the answer was a qualified no. In this paper, we briefly review some of the many advances made in community intervention trials, and address in more detail the challenges ahead.