• obsessive compulsive disorder;
  • cognitive therapy;
  • psychotherapy;
  • group

Jónsson H, Hougaard E, Bennedsen BE. Randomized comparative study of group versus individual cognitive behavioural therapy for Obsessive Compulsive Disorder.

Objective:  The primary aim of the study was to compare the effectiveness of group and individual cognitive behaviour therapy (CBT) for obsessive compulsive disorder (OCD).

Method:  One hundred and ten out-patients with OCD were randomly assigned to 15 sessions of either group CBT or individual CBT. Outcome measures were administered before and after treatment, as well as at 6- and 12-month follow-ups. The study was supplemented by a meta-analysis of accomplished comparative studies of group vs. individual CBT for OCD.

Results:  Large and stable pre–post effect sizes were found for both treatment conditions in the study (= 1.06–1.24 on the Yale-Brown Obsessive Compulsive Scale). There were no significant between-group differences in outcome at any data point (ds = −0.13 to 0.15). The meta-analysis of four accomplished comparative studies (including the present one) found a between-group mean effect size of = 0.15 favouring individual over group CBT at posttreatment (95% confidence interval, −0.12, 0.42).

Conclusion:  The results of this study suggest that OCD can be treated effectively with a group format of CBT, thus sparing some therapist resources, although the four accomplished comparative studies do not rule out the possibility of a small superiority of individually conducted CBT.