{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T15:40:28Z","timestamp":1792424428165,"version":"4.5.0"},"reference-count":46,"publisher":"American Medical Association (AMA)","issue":"10","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Netw Open"],"abstract":"\n Importance<\/jats:title>\n Given the high prevalence, chronicity, and associated disability of obsessive-compulsive disorder (OCD), optimizing treatment is a global priority. The Bergen 4-day treatment (B4DT), a concentrated exposure-based intervention, may reduce treatment burden and improve access to evidence-based care.<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n To evaluate the efficacy of B4DT compared with internet-based cognitive behavioral therapy (iCBT) in reducing OCD symptom severity.<\/jats:p>\n <\/jats:sec>\n \n Design, Setting, and Participants<\/jats:title>\n Single-center randomized controlled trial (1:1 allocation). Between May 8, 2024, and August 8, 2025, adults (aged 18 to 72 years) with OCD were enrolled and were followed up for 3 months. Key exclusion criteria included schizophrenia, bipolar disorder, acute suicidality, substance dependence, and recent psychopharmacological changes. Outcomes were assessed at baseline, 6 weeks, 8 weeks (posttreatment), and 3 months (follow-up) by masked evaluators.<\/jats:p>\n <\/jats:sec>\n \n Interventions<\/jats:title>\n Patients were randomized to B4DT (including preparatory sessions) or an 8-week unguided iCBT program.<\/jats:p>\n <\/jats:sec>\n \n Main Outcomes and Measures<\/jats:title>\n The primary outcome was the change in OCD symptom severity, measured by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Secondary outcomes included self-reported OCD (OCI-R), dysfunctional cognitions, quality of life, depressive symptoms, experiential avoidance, global functioning, self-esteem, and treatment satisfaction.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n A total of 253 individuals were screened, and 119 were enrolled after 53 were found to be ineligible and 81 declined to participate. Sixty of the 119 randomized participants (mean [SD] age, 33.5 [10.1] years; 79 [66.4%] women) were assigned to B4DT and 59 to iCBT. The primary analysis included all randomized participants (intention-to-treat). B4DT was associated with significantly greater reductions in OCD symptoms (Y-BOCS) than iCBT, with large effects at posttreatment (mean [SE] difference, \u22127.9 [0.9]; 95% CI, \u22129.7 to \u22126.0; Hedges\n g<\/jats:italic>\n , \u22121.6) and sustained effects at 3-month follow-up (mean [SE] difference, \u22125.6 [1.1]; 95% CI, \u22127.8 to \u22123.4; Hedges\n g<\/jats:italic>\n , \u22121.0). Secondary outcomes consistently favored B4DT. Response and remission rates at 3-month follow-up were higher with B4DT (35 of 57 [61.4%] vs 11 of 44 [25.0%] and 24 of 57 [42.1%] vs 6 of 44 [13.6%], respectively).\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions and Relevance<\/jats:title>\n In this randomized clinical trial of 119 adults with OCD, B4DT was superior to iCBT in reducing OCD symptom severity, with sustained benefits. Its brief, concentrated format may represent a scalable strategy to improve access to effective OCD treatment globally.<\/jats:p>\n <\/jats:sec>\n \n Trial Registration<\/jats:title>\n \n German Clinical Trials Register:\n DRKS00034236<\/jats:ext-link>\n <\/jats:p>\n <\/jats:sec>","DOI":"10.1001\/jamanetworkopen.2026.39281","type":"journal-article","created":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T15:00:27Z","timestamp":1792422027000},"page":"e2639281","source":"Crossref","is-referenced-by-count":0,"title":["Concentrated Exposure Therapy vs Internet-Based Cognitive Behavioral Therapy for Obsessive-Compulsive Disorder"],"prefix":"10.1001","volume":"9","author":[{"given":"Lena","family":"Jelinek","sequence":"first","affiliation":[{"name":"Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, 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