Cognitive behavioural therapy (CBT) including exposure and response prevention (ERP) is an effective treatment for preadolescent children with obsessive compulsive disorder (OCD); however, there is a need to increase access to this treatment for affected children.

This study is a preliminary evaluation of the efficacy and acceptability of a brief therapist-guided, parent-led CBT intervention for pre-adolescent children (5–12 years old) with OCD using a non-concurrent multiple baseline approach.

Parents of 10 children with OCD were randomly allocated to no-treatment baselines of 3, 4 or 5 weeks before receiving six to eight individual treatment sessions with a Psychological Wellbeing Practitioner. Diagnostic measures were completed prior to the baseline, 1-week post-treatment, and at a 1-month follow-up, and parents completed weekly measures of children’s OCD symptoms/impairment.

Seventy percent of children were ‘responders’ and/or ‘remitters’ on diagnostic measures at post-treatment, and 60% at the 1-month follow-up. At least 50% of children showed reliable improvements on parent-reported OCD symptoms/impairment from pre- to post-treatment, and from pre-treatment to 1-month follow-up. Crucially, the intervention was acceptable to parents.

Brief therapist-guided, parent-led CBT has the potential to be an effective, acceptable and accessible first-line treatment for pre-adolescent children with OCD, subject to the findings of further evaluations.