Date of Submission


Degree Type


Degree Name

Doctor of Psychology (PsyD)



Department Chair

Robert A. DiTomasso, Ph.D., ABPP

First Advisor

Robert A. DiTomasso, Ph.D., ABPP, Chairperson

Second Advisor

Bruce Zahn, Ed.D., ABPP

Third Advisor

Barbara B. Williams, Ph.D.


This single subject case study was conducted to determine the usefulness of a new measure, the Inventory of Cognitive Distortions (lCD). The main purpose was to determine the effectiveness of the ICD in noting changes in dysfunctional thinking during cognitive behavioral therapy. Because of the high incidence of depression in the population, a subject diagnosed with Major Depressive Disorder was determined to be the most appropriate choice for assessing the effectiveness of this measure in the clinical setting. The cognitive behavioral treatment implemented was a manualized approach using Gilson and Freeman's (1999), Overcoming Depression. This treatment was a collaborative effort between the individual and the therapist; the individual using the manual for homework assignments and for reinforcement of what was learned in the therapeutic sessions. From baseline to termination the patient attended a total of 10 sessions, with a follow-up approximately one month later. Assessment involved clinical interviews, Multimodal Life History Inventory (Lazarus & Lazarus, 1991), the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID I; First, M.B., Spitzer, R.L., Gibbon, M., & Williams, J.B.W., 1997), the Beck Depression Inventory (BDI; Beck, Steer & Brown, 1996) the Beck Anxiety Inventory (BAI; Beck, Epstein, Brown & Steer, 1988), and the Beck Hopelessness Scale (BHS; Beck, Weissman, Lester, Trexler, 1974), the Inventory of Cognitive Distortions (lCD: Yurica & DiTomasso, 2002), and the Dysfunctional Attitude Scale (DAS; Beck & Weissman, 1978; Weissman, 1979). The ICD and the DAS were used at baseline, at termination, and at follow-up to note any changes (or cessation) in dysfunctional thinking throughout treatment. The research findings indicated reductions in self-report scores as the client and therapist worked through the manualized treatment. Homework was an important component. Three self reports (BDI,BAI, BHS) were completed for each session. Reading and working on the manual and the chapter exercises was essential; other homework varied according to the individual's needs. Those included completion of a Daily Thought Record (DTR) to determine patterns and/or triggers in distorted thinking. Because the client seemed to struggle with passive-aggressive tendencies she used writing as a vehicle to express her feelings calmly; she learned and practiced, in session, the assertiveness skills which were to be used beyond the therapeutic setting. The results indicated that cognitive behavioral therapy, in a manualized format, was effective in reducing depressive symptoms and that the lCD was able to indicate changes in the distorted thinking of the subject, as hypothesized.