Predicting patient perceptions of psychotherapy session impact

Given relative consensus in the empirical literature about the beneficial impact of psychotherapy, researchers have sought to identify the effective ingredients in psychotherapy by relating process to outcome. A review of this literature reveals inconsistent findings. In response, researchers have developed strategies involving micro- or sub-outcomes. One type of micro-outcome strategy is therapy session impact: the immediate effects of session process on the participants perception of the session.

The primary purpose of this study was to apply the therapy session impact strategy with respect to process variables related to patient perceptions of session depth/value, smoothness/ease and goodness. A secondary purpose of this study was to explore these session process variables as a function of differing levels of patient pathology.

Thirty-three patients and their therapists were recruited for the study. Three audiotaped sessions, patient completed Session Evaluation Questionnaires and a Millon Clinical Multiaxial Inventory were obtained from each patient. Sessions were rated on a wide range of iv process variables using the Vanderbilt Psychotherapy Process Scale.

Results indicated that process variables were not stable over sessions within patient-therapist dyads. Results also indicated that process variables did not predict patient perceptions of session goodness. Although several process variables predicted patient perceptions of depth/value or smoothness/ease, these findings were not consistent over sessions. Consistent differences in process variables were not found over sessions with patients having different levels of psychological disturbance.

Overall, the present study indicated variability in both the process variables and the usefulness of process variables to predict patient perceptions of impact over sessions. These findings are consistent with prior research which contradicts the assumption of the homogeneity of process variables. The present findings support the development of psychotherapy research strategies that take into consideration the heterogeneity of process variables over sessions.