Interpersonal psychotherapy (IPT) research has addressed outcome more than mechanism. This study used the novel Interpersonal Psychotherapy Outcome Scale (IPOS) to test the theoretical axiom that symptomatic improvement in IPT reflects resolution of interpersonal problem areas. The IPOS rates change in focal interpersonal problem areas on a 5-point scale. Patients (N = 24) and therapists (N = 7) in a time-limited IPT outcome study of dysthymic disorder, and patients (N = 11) in an open trial for posttraumatic stress disorder, completed the IPOS at treatment termination. All responding dysthymic subjects (N = 24) and therapists (N = 21) reported interpersonal gains: dysthymic patients scored 4.39 (SD = 0.52) out of 5, therapists 4.27 (0.53). Posttraumatic stress disordered patients rated 4.75 (0.34). Patient and therapist IPOS ratings correlated with objectively measured symptomatic improvement with full or trend statistical significance. Despite methodological limitations, initial testing of the IPOS supports the theorized link between resolving interpersonal crises and improvement in IPT.
*Department of Psychiatry, Weill Medical College of Cornell University, New York, New York; †New York State Psychiatric Institute, New York, New York; and ‡Department of Public Health, Weill Medical College of Cornell University, New York, New York.
Supported in part by grant MH-49635 from the National Institute of Mental Health.
Send reprint requests to John C. Markowitz, MD, New York State Psychiatric Institute, 1051 Riverside Drive, Unit# 129, New York, NY 10032.