Home-based treatment of obsessive-compulsive patients: intersession interval and therapist involvement

In a 2 x 2 factorial design massed vs spaced and therapist vs self-controlled exposure were compared with obsessive-compulsive patients. Intersession interval was varied keeping constant the length of exposure time and number of exposure sessions. Treatment in all conditions was home based. Treatment led to highly statistical and significant improvements on all measures. Massed exposure was as effective as spaced exposure; self-controlled exposure proved to be as effective as therapist-controlled exposure.