Restricted (Penn State Only)
Youn, Soo Jeong
Graduate Program:
Doctor of Philosophy
Document Type:
Date of Defense:
May 17, 2016
Committee Members:
  • Louis Georges Castonguay, Dissertation Advisor
  • Louis Georges Castonguay, Committee Chair
  • Stephen Jeffrey Wilson, Committee Member
  • Jeffrey Hayes, Committee Member
  • Peter Cm Molenaar, Outside Member
  • therapist effects
  • practice oriented research
  • practice research networks
  • psychotherapy process
The presence of therapist effects, or the variability in the contribution of individual therapists to psychotherapy outcomes, is a well known phenomenon in psychotherapy, present in both clinical trials as well as routine clinical practice. However, what leads to therapist variability remains an area of continued exploration. Using a large dataset (N=9,188 clients, 520 therapists) collected in a large practice research network, the current study examines therapist variability using a multidimensional outcome measure addressing various dimensions of functioning, and different research methodologies assessing client outcome; rate of change and pre-post magnitude of change. The results of the multilevel model showed a range in the therapist accounted variance for rate of change (2-19%) and magnitude of change (0.75-11%) for the various subscales. Overall, the estimated therapist variance was higher when rate of change was used as the outcome assessment. Furthermore, the results also showed little overlap between the top therapists in each of the domains of functioning across the two types of outcome used. Taken together, these results suggest that differential skills may be required by therapists to foster different types of improvement. Additionally, the current study provides preliminary support for both specificity of expertise in some domains, as well as to a general construct of therapist competence across other areas of client distress. Clinical and training implications are discussed.