Factors of treatment success in psychotherapy: a within-therapist analysis of early session processes.

While psychotherapy is generally effective, outcomes can vary significantly across patients, even when treated by the same therapist. This study employed a mixed-methods design to examine early indicators of treatment success by analyzing contrasting outcomes within individual therapists' caseloads. Treatment success was determined by patients achieving a clinically significant change on the Brief Symptom Inventory's Global Severity Index (BSI-GSI). The Reliable Change Index (RCI) was used to calculate these changes, adjusting to account for measurement error and regression to the mean. Unsuccessful cases are defined as those with no reliable change or deterioration. Data from six patients treated by three psychodynamic therapists were analyzed (each therapist having one successful and one unsuccessful case). Quantitative analyses of psychological assessments and early treatment measures, along with qualitative analyses of third session transcripts, were conducted. In successful cases, the patients reported higher levels of depression, interpersonal distress, and social avoidance/anxiety, but also greater personal insight prior to the treatment. Patients in successful cases also rated lower session smoothness compared to their therapists' ratings early in treatment. These divergent views are likely due to higher ratings of therapists' exploration of uncomfortable feelings in the successful treatment sessions. In addition, these external raters observed that in the successful cases, therapists employed higher overall levels of psychodynamic-interpersonal techniques during the third session than in their unsuccessful cases. Results highlight the importance of how initial severity and emotional expression in the early stage of psychotherapy may help lay the foundation for successful treatment outcomes.