Date of Submission


Degree Type


Degree Name

Doctor of Psychology (PsyD)



Department Chair

Michelle Lent, PhD

First Advisor

Dr. Collins, PsyD

Second Advisor

Stephanie Felgoise, PhD, ABPP

Third Advisor

Robert DiTomasso, PhD, ABPP


Bariatric surgery is the most effective long-term treatment for severe obesity. Although bariatric surgery results in significant weight loss for many patients, variability exists in expectations surrounding postoperative outcomes. Therefore, this study examined two psychosocial factors that may contribute to variability in weight loss expectations among adults seeking bariatric surgery: affective disorders and locus of control. Specifically, it was hypothesized that individuals scoring higher on external measures of locus of control would report lower weight loss expectations for surgery than those scoring higher on internal measures of locus of control (as measured by the Levenson’s Multidimensional Locus of Control Scale, Weight Loss Locus of Control Scale, and the Goals and Weight-Related Questionnaire). Additionally, it was hypothesized that a history of or current presence of an affective disorder would be associated with lower weight loss expectations for surgery, as measured by the Goals and Weight-Related Questionnaire. Participants were recruited from a weight-loss surgery program at a large comprehensive rural medical center. Regression models were used to analyze data to test the hypotheses. Findings from this study may be relevant to bariatric surgery programs as they work with candidates pursuing surgery; specifically, results may inform the assessment and treatment of the bariatric surgery population.