Self-Consciousness, Outcome Expectancy, And Motivational Factors In A Behavioral Eating/weight Control Program

Date of Award




Degree Name

Doctor of Philosophy (Ph.D.)




The present study was undertaken to extend the findings of an earlier study which tested the hypothesis that expectancy and self-consciousness variables interact to predict success in a 7-week behavioral eating/weight control program. The hypothesis that high private self-consciousness would predict greater outcome success in conjunction with positive expectancy received substantial support. Unexpectedly, it was found that "moderate" levels (as opposed to higher levels) of several of the "expectancy" measures predicted success. The most consistently effective "expectancy" predictor index had as one of its components desired weight loss; this variable (conceptually a motivational rather than expectancy factor) actually accounted for the more moderate index values which had predicted greater success. It appeared that two conceptually distinct variable types, expectancy versus motivation, had been confounded in the original study, making interpretation and attribution of predictive efficacy impossible.A major purpose of the replication study was to isolate expectancy from motivational predictor variables and identify the differences in their relationship to weight loss over the course of treatment. The intersection of two "content" dimensions in the present study--i.e., (1) an expectancy factor versus a motivational factor, and (2) weight-loss issues versus control over eating problem issues--allowed comparison of four predictor content types: (1) expected weight loss, (2) desired weight loss, (3) expectancy of control over eating problems, and (4) importance of control over eating problems. The relationship between each of these indices and weight loss over the course of treatment was examined. Predictor efficacy issues, such as (1) time in the treatment sequence when prediction was most effective (i.e., week-1 versus week-3), and (2) length of prediction period having greatest accuracy (i.e., short-term versus long-term) were examined independently for each of the predictor types.The four predictor types demonstrated different weight loss prediction patterns, supporting the hypothesis that expectancy and motivational attitudes operate differently and provide unique descriptive and predictive information regarding treatment outcome. Self-consciousness failed to correlate with weight loss. The importance of distinguishing between weight loss and eating control issues, both as independent measures and in the evaluation of treatment outcome, was also considered.


Psychology, Clinical

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