Expectations in the treatment of obesity.

The initial efficacy expectations and outcome expectations held by 147 women participating in two weight reduction programmes were assessed and found to be partially related to drop-out and the weight loss attained. Expectations were revised as treatment progressed, but changes were not closely correlated with changes in weight over the same period. Initial outcome expectations were associated with higher weight, and lower social class and verbal ability, but not the number of previous attempts to lose weight.