BackgroundThe Bergen 4-day treatment (B4DT) is a concentrated exposure-based treatment for patients with Obsessive-Compulsive Disorder (OCD) delivered during four consecutive days. The B4DT has in a number of effectiveness studies demonstrated promising results as approximately 90% of patients gain reliable clinical change post-treatment and nearly 70% are recovered on a long-term basis.MethodsThe current study is the first randomized controlled trial evaluating the effects of the B4DT. Forty-eight patients diagnosed with OCD were randomized to B4DT, self-help (SH), or waiting list (WL) with 16 patients in each condition. All participants randomized to the B4DT underwent the treatment without any attrition.ResultsThe B4DT yielded significantly better effects than control conditions on measures of OCD, depression, and generalized anxiety. The response rate (≥35% reduction of the individual patient’s pre-treatment Y-BOCS score) was 93.8% in B4DT, 12.5% in SH and 0% in WL, while remission rate (response criterion is fulfilled and the post-treatment Y-BOCS score is ≤12 points) was 62.5%, 6.3%, and 0%, respectively. Furthermore, patients who had received the B4DT, showed improved work- and social functioning. None of the patients treated with B4DT showed signs of deterioration. In comparison, one patient in the SH condition was in remission, and one showed significant clinical improvement, whereas the remaining showed no change.ConclusionThe results indicate that the B4DT is an effective treatment for patients suffering from OCD.Clinical Trial Registrationwww.ClinicalTrials.gov, identifier NCT02886780.

Sørlandet Hospital in Norway has a history of offering patients with obsessive-compulsive disorder (OCD) cognitive behavior group therapy using 12 weekly sessions of 2.5 h each. A previous evaluation of this treatment has shown that 51.9% did not respond at post-treatment. Recently, a highly concentrated group-treatment format, the Bergen 4-day treatment (B4DT), has been shown to help more than 90% of patients with OCD post-treatment. Based on these positive results, it was decided to explore whether the B4DT could be a feasible format for delivering ERP at another clinic. Thirty-five consecutively recruited patients were included in the current pilot study, and assessed at pre-treatment, post-treatment, and 3-month follow-up. Treatment response rate (35% reduction in OCD-symptom score) was 94% at post-treatment, and 80% at follow-up. Seventy-four percent were in remission at post-treatment and 68% at follow-up. Only one patient dropped out of treatment. The patients were highly satisfied with the treatment content and format. The results indicate that the 4-day treatment could successfully be implemented at a new clinic.