The relationship of patient difficulty to therapist performance in interpersonal psychotherapy of depression.

The efficacy of Interpersonal Psychotherapy (IPT) in the treatment of ambulatory major depression was demonstrated in the recently completed NIMH Treatment of Depression Collaborative Research Program (Elkin et al. 1986). Factors which enhance or impede the administration of the treatment delimit effective patient care and should therefore be understood. This report examines the relationship of pretreatment patient attitudes and in-treatment patient difficulty to the ability of therapists to competently conduct IPT, using data from a training program in IPT. The hypothesis was that the patient's ability and willingness to establish a relationship and undertake the task demands of therapy would influence the therapist's ability to administer treatment. Patient difficulty was found to be strongly related to both therapists' and supervisors' judgements of therapist performance during IPT sessions: when patients were more difficult, therapists were judged to have performed more poorly. Patients' preexisting negative expectations about the potential outcome of treatment were associated with patient difficulty and poorer therapist performance, while the level of presenting symptomatology was not. Thus, it appears that the patient's ability to engage in a productive therapeutic relationship rather than the severity of his presenting problems influenced the therapist's ability to competently perform IPT. The findings regarding the relationship of patient difficulty to ratings of therapist performance suggest that patient difficulty should be taken into account in assessing therapist competence, whether for studies of therapeutic efficacy or for clinical supervision and training in general.