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Date of Award


Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

James B. Lane, PhD

Second Advisor

Robin Shallcross, PhD, ABPP


The field of psychology lacks a comprehensive understanding of the process by which a therapist chooses his or her theoretical orientation. This choice is central to a therapist’s professional identity, impacting clinical approach, conceptualization, supervision, and the length, quality, and outcome of treatment. Orientation guides research, and licensing organizations, insurance companies, and colleagues often ask psychologists to identify with a particular orientation (Fitzpatrick, Kovalak, & Weaver, 2010). Additionally, the interaction between a therapist’s personality and his or her choice of theoretical orientation affects his or her career satisfaction (Arthur, 2001). Identifying and practicing from a complementary orientation is therefore an important goal for a therapist, and understanding the underlying process and contributing factors can help therapists more efficiently identify a matching orientation. Therapists who are more aware of their personality characteristics may find the process of identifying a complementary orientation less distressing than those who are less aware of their personality. Researchers have explored variables affecting choice of orientation, including the roles of training, personality, and early clinical experiences. In the present study, I measured doctoral psychology graduate students’ ambiguity tolerance (AT) via the Multiple Stimulus Ambiguity Tolerance Scale-II (MSTAT-II) (McLain, 2009) to understand how this trait impacts choice of orientation. I hypothesized that there would be significant differences in average MSTAT-II scores between insight-oriented, integrative, and behaviorally-oriented theoretical orientation groups, with higher MSTAT-II scores associated with insight-oriented, moderate scores associated with integrative, and lower scores associated with behaviorally-oriented. The results suggested significantly higher AT in the insight-oriented group (n=29) than integrative (n=60) and behaviorally-oriented groups (n=31). No significant difference in AT was identified between integrative and behaviorally-oriented groups. Overall, the results suggested a medium effect size between the two variables (η2 = 11.6%). Implications for training are discussed.


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