Degree Type

Honors Capstone Project

Date of Submission

Spring 5-1-2007

Capstone Advisor

Kevin S. Masters, Ph.D.

Honors Reader

Paula M. Trief, Ph.D.

Capstone Major


Capstone College

Arts and Science

Audio/Visual Component


Capstone Prize Winner


Won Capstone Funding


Honors Categories

Social Sciences

Subject Categories

Health Psychology | Other Psychology | Psychology


Background: Bariatric weight loss surgeries are an increasingly popular last resort option for obese individuals attempting to lose weight. Though these surgeries often produce substantial weight loss outcomes, especially in a short-term follow-up period, many individuals that undergo these procedures are unable to achieve long-term weight loss success. Within the bariatric surgery literature several psychological variables have been implicated in this long-term failure to maintain weight loss. Purpose: This study was designed to assess the effects of psychological variables on weight loss success after surgery through a meta-analytic review. Methods: The effect sizes from 10 studies were calculated and combined to determine the overall effect size across the data pool. The variables of depression and anxiety were isolated to determine the effect size within this narrower subset of studies. A test of homogeneity was performed to determine the extent to which the overall effect was representative of the findings across studies. Results: No significant relationship was found between pre-surgical general psychopathology and weight loss (r=.082, p=.122). A small non-significant positive correlation was found between pre-surgical anxiety and depression and weight loss (r=.177, p=.13). Both data sets were found to be heterogeneous (general psychopathology: Q=19.15, p=.024, I^2=52.99; anxiety/depression: Q=8.34, p=.04, I^2=64.01). Conclusions: The results indicate that pre-surgical psychopathology is not predictive of weight loss success after bariatric surgery. Given the lack of standardized test data for psychopathology prior to these surgeries and given the poor quality of data reporting in the existing literature, we recommend further investigation in this field using validated instruments, especially concerning anxiety and depression.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.



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