Efficacy of a parent-based treatment for children and adolescents with obsessive-compulsive disorder: Protocol of a multiple baseline, single-case experimental design study.

Background: Pediatric obsessive-compulsive disorder (OCD) is a severely impairing disorder, associated with high levels of family accommodation (FA). Approximately 40 % of youth do not benefit from first-line treatment options (cognitive behavioral therapy or pharmacotherapy). Supportive Parenting for Anxious Childhood Emotions (SPACE) is a parent-based treatment, teaching parents to reduce FA and increase supportive parenting, thereby aiming to improve the child's OCD. This article presents the protocol of a multiple baseline single-case experimental design (SCED) study to test the efficacy of SPACE in reducing OCD severity and FA in youth with OCD. Methods: This SCED consists of a baseline, treatment, and follow-up phase. In total 25 youth (7-18 years) with OCD, who previously received cognitive behavioral therapy (CBT) unsuccessfully, aborted treatment early, or were not able to receive CBT due to too high levels of OCD/anxiety, and their parents will be included. They will be randomly allocated to one of three baseline phase options (4, 6 or 8 weeks). The treatment phase consists of 12 weekly sessions of SPACE with parents. Throughout all phases, OCD severity and FA will be briefly assessed thrice a week. Standard clinical measurements assessing OCD severity and FA and secondary parameters will be conducted at six timepoints, till 6 months follow-up. Conclusion: Combining the innovative SPACE treatment with a SCED provides detailed insight into the relationship between OCD and FA over time. Studying this in clinical practice in complex cases that are normally understudied, helps to improve more personalized care for youth with OCD.