ISRCTN74790966ISRCTN08/05/2026Oxford Health NHS Foundation TrustComparison of focused cognitive behavioural therapy and treatment as usual in the treatment of obsessive compulsive disorderRandomised parallel trial comparing the efficacy of focused cognitive behavioural therapy versus treatment as usual for obsessive compulsive disorder01/06/2026Anticipated68Recruitinghttps://www.isrctn.com/ISRCTN74790966InterventionalAllocation: Randomized controlled trial; Masking: Open (masking not used); Control: Active; Assignment: Parallel; Purpose: Treatment;Not ApplicablePatients with a primary problem descriptor of obsessive compulsive disorder as identified at triage and confirmed at first assessment with therapist.The present randomised control trial aims to compare the efficacy of focused CBT with treatment as usual for OCD at two NHS Talking Therapy services . Focused CBT draws on the methodology outlined by Clark et al. (1999), Aslam et al. (2025), and Johnsen et al. (2025). Focused CBT sessions are supported by workbook modules, with treatment involving the development of a shared understanding of patients' OCD difficulties and the introduction of cognitive and behavioural strategies aimed at addressing factors maintaining OCD symptoms. Treatment will involve six to eight 30-minute sessions delivered online or face-to-face by psychological wellbeing practitioners. Treatment as usual at the services includes Guided Self-Help (GSH) and/or computerised CBT (cCBT). Interventions at both services can be delivered via phone, face-to-face, or MS Teams, depending on the individual’s preference. Both GSH and cCBT are classified as low- intensity, Step Two interventions. GSH involves a treatment planning session lasting up to 45 minutes, followed by six to eight 30-minute sessions with a PWP. Self-help materials are provided between sessions, with treatment focusing on psychoeducation and cognitive and behavioural skills. Meanwhile, cCBT is an online intervention delivered via the ‘SilverCloud’ platform. An initial ‘set-up’ call, lasting up to 20 minutes, is offered to explain the OCD programme. Patients then access the programme online, working through modules independently. Throughout the programme, patients are offered up to six online reviews, lasting up to 15 minutes each. Patients will be randomly allocated (using sampling without replacement) to either the intervention (focused CBT) or TAU (cCBT or GSH) condition on a 1:1 ratio in blocks of four using an online system called ‘Sealed Envelope’. A central randomisation system will be used to ensure allocation concealment, with an independent member of the research team not involved in the consent process, assigning participants to their treatment conditions. Clinical teams will be informed of the participant’s intervention condition, with services assigning therapists randomised to the condition. It will not be possible to blind therapists or participants to the intervention.027/09/2027NoNot expected to be made available.