The article conducts a review of the literature that is available on behavior change intervention. It looks at various articles and identifies those that are high in external and internal validity. Accordingly, it is a meta-analysis that looks at the nature of research conducted before in behavioral interventions. The participant populations are also analyzed, especially for their descriptions provided and the representativeness of the drawn samples. This research comprised that which was published in scholarly journal between 1996 and 2000 and dealt with three subjects including dietary changes, smoking cessation, physical activity. The ...