Behavior therapy versus "will power" in the management of obesity.

In a study of the management of obesity 43 patients were randomly assigned to behavior therapy, will power, and no-treatment control groups. The behavioral treatment involved contingency contracting, stimulus control, self-monitoring, energy expenditure, and group reinforcement procedures over an 18-week period. The will power patients were told to do the same thing as the behavior therapy patients; however, instead of having formal contingencies and meeting regularly, they were told to apply "will power" on their own, as this was the most important aspect of losing weight. The third group was a standard no-treatment control group. Analyses of covariance indicated that (a) the behavior therapy group lost significantly more weight than the will power (p less than .05) and no-treatment control (p less than .01) groups, and (b) the will power and no-treatment control groups did not differ significantly from each other. An 18-week maintenance follow-up of the behavior therapy group indicated that there was no significant weight gain from the end of treatment to follow-up. Also, an analysis of time spent per patient suggested that the behavioral treatment employed in this study was more efficient than previous treatments.