Date of Award

6-2026

Degree Name

Doctor of Philosophy

Department

Counselor Education and Counseling Psychology

First Advisor

Eric Sauer, Ph.D.

Second Advisor

Jennifer Foster, Ph.D.

Third Advisor

Ya Zhang, Ph.D.

Keywords

Attachment styles, mentalization, psychotherapy, treatment outcomes, working alliance

Abstract

A burgeoning area of research within the past 30 years has sought to identify which specific therapist factors contribute to differential treatment outcomes (Barkham et al., 2017). The purpose of the current naturalistic study was to explore how two personal characteristics of therapist trainees, mentalization capacity and attachment styles, impact early treatment outcomes at two Midwestern psychology training clinics. This study also examined whether therapist mentalization and the working alliance interacted to influence client outcomes. Therapists completed the Mentalization Scale (MentS; Dimitrijević et al., 2018) and the Experiences in Close Relationships scale (ECR; Brennan et al., 1998), while the Working Alliance Inventory–Short Revised (WAI-SR; Hatcher & Gillaspy, 2006) and the Outcome Questionnaire-45.2 (OQ-45.2; Lambert et al., 1996) were used to assess therapeutic alliance and client outcomes, respectively. Client psychological distress was measured at intake and prior to each therapy session. Participants included 10 therapist–client dyads.

Due to the exploratory nature of this study, no formal research hypotheses were specified. Two level growth curve modeling was used for the main analyses. Interestingly, therapist mentalization did not influence treatment outcomes. However, therapist attachment anxiety predicted improved client outcomes early in treatment. Moreover, therapists higher in attachment anxiety with greater mentalizing capacities were associated with poorer client outcomes. In contrast, higher mentalizing capacities combined with greater attachment avoidance predicted improved client outcomes. These findings highlight the complex interplay between therapist attachment and mentalization capacities in shaping early psychotherapy outcomes. Research, training, and clinical implications are provided.

Access Setting

Dissertation-Open Access

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