An increasing amount of outcome research supports the efficacy of Short Term Psychodynamic Psychotherapy (STPP) for a wide range of psychological disorders, reporting effect sizes in meta-analyses between 0.50 and 1.40 (for review see Shedler, 2010). Mapping mechanisms of change in the STPP process can be considered the major challenge of STPP for the decades to come.

This study focuses on STPP with Obsessive-Compulsive (OC) patients and tests the hypothesis that the progressive elimination of OC symptoms throughout an STPP process is correlated to a parallel process of change at the level of interpersonal characteristics.

Mixed quantitative-qualitative analyses of data of Short Term Psychodynamic Therapies with four OC patients are presented. Repeated Measures analyses are performed to study intra-subject associations between intensity of OC symptoms (measured by General Health Questionnaire, GHQ-12, and Obsessive-Compulsive Inventory, OCI-R) and interpersonal characteristics (measured by Inventory of Interpersonal Problems, IIP-32).

Observed associations between evolutions in general interpersonal characteristics and general complaints were significant yet inconsistent across the patients. Qualitative analyses, however, revealed similarities on the level of specific interpersonal characteristics, in this respect that all patients struggled to escape the suffocating impact of parental figures and/or romantic partners.

Rather than elaborating a general interpersonal style (cfr. Desmet et al., 2008), the results suggest that a progressive elaboration of parent-child and partner relationships is a crucial characteristic of the STPP process with OC patients. Limitations of the study are the small sample size and the absence of contrast- and control groups.