The influence of interpersonal problems and symptom severity on the duration and outcome of short-term psychodynamic psychotherapy.

This naturalistic outcome study investigated validity aspects of the Inventory of Interpersonal Problems (IIP [Horowitz, Strauß, & Kordy, 1995]). The sample consisted of 180 patients who received short-term psychodynamic psychotherapy for an average number of 7.8 sessions and an average duration of 3.4 months. Small changes in pre-post-measures imply that the IIP is not to be recommended as an instrument for outcome evaluation in short-term psychotherapy, due to the traitlike character of its items. However, we showed by path analyses that a higher score on the affiliative dimension of the interpersonal circumplex goes along with a better treatment outcome. The influence of the dominance dimension is gender specific: male patients (who generally showed more dismissive and introverted behavior in this sample) received, if dismissive and introverted, a longer introductory therapy, whereafter they - in cases of high symptom load - were often referred to long-term treatment. Dominant male patients and, in general, female patients with high symptom scores, were referred faster, after only a few sessions. Results are discussed under aspects of adaptive therapist behavior.