The Community Intervention Trial for Smoking Cessation (COMMIT)

Abstract The Community Intervention Trial for Smoking Cessation (COMMIT), funded by the U.S. National Cancer Institute (NCI), was a large‐scale study involving 11 pairs of communities in North America, matched on geographic location (state or province), size, and sociodemographic factors. Communities were randomized within pairs to active community‐based intervention versus comparison. Thus, COMMIT is an example of a group randomization design (also called a cluster randomization design), in which intact groups (clusters), rather than individuals, are randomly allocated to intervention condition. Randomization of communities was used in COMMIT to obtain an unbiased assessment of the intervention effect; randomization also provided the basis for the statistical analysis.