Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Donald A. Williamson


Comparative outcome and process research approaches have not yielded a complete understanding of the beneficial processes of psychotherapy. A recent approach to studying psychotherapy has involved the study of general stages of change that occur during all types of psychotherapy which are positively related to treatment outcome. The purpose of the present investigation was to test a stage of change model for the treatment of the eating disorders anorexia and bulimia nervosa. A review of the literature suggested that there were four general symptom domains that may be related to positive outcome in the treatment of eating disorders. Based on this information a stage of change model was proposed. In order to examine the validity of such a model, a self-report inventory (Eating Disorder Symptom Profile, EDSP) was developed so that the four symptom domains could be assessed at different stages of treatment. Study 1 of this investigation was devoted to the development of the change model and the development of the EDSP. Study 2 involved an examination of the psychometrics of the EDSP, and an initial examination of the stage of change model. Results showed the EDSP to contain 4 factors which were conceptually similar to the 4 symptom areas of the stage of change model. The instrument was found to have good test-retest reliability and moderate to good support for the validity of the EDSP factors. In Study 2, the EDSP was administered to a group of 50 eating disorder patients who were at different points in treatment. The symptom profiles of the EDSP were examined in order to see if they corresponded with predictions made by the stage of change model. Cluster analyses and examination of individual profiles were generally supportive of the model, although the model was not able to account for all patterns of symptomatology evidenced by the patients on the EDSP. Results were discussed with respect to the psychometric characteristics of the EDSP and their implications for testing the stage of change model. Also, suggestions for the refinement of the stage of change model and the EDSP were presented.