RESUMEN
OBJECTIVE: To examine the efficacy of the parent-led intervention Supportive Parenting for Anxious Childhood Emotions (SPACE) relative to a low-dose version of the protocol among children and adolescents with clinically significant anxiety and/or obsessive-compulsive disorder (OCD). METHOD: 68 youth (7-17) with anxiety/OCD and their parents were randomized to receive 12 weekly telehealth SPACE sessions (SPACE-Standard) or bibliotherapy plus 4 telehealth sessions over 12 weeks (SPACE-light). After screening, assessments were conducted via videoconferencing at baseline, post-treatment, and one-month follow-up. Independent evaluators were blind to treatment condition. RESULTS: Treatment condition did not predict whether a participant responded to the intervention (SPACE-Standard = 70%; SPACE-Light = 68%), nor was treatment condition a predictor of anxiety severity, parent-reported anxiety, or parent-/child-reported functional impairment at post-treatment or one-month follow-up. Youth in SPACE-Light self-reported higher post-treatment anxiety than youth in SPACE-standard, though this was no longer significant at one-month follow-up. Parent-reported family accommodation total change scores were associated with anxiety severity at post-treatment across both arms. CONCLUSION: This is the second randomized controlled trial (RCT) evaluating SPACE and provides further support for the efficacy of this intervention both in standard and low-dose formats. This study provides support for parent-led anxiety treatment targeting family accommodation as a primary mechanism of change and extends evidence of efficacy to a more clinically diverse sample. TRIAL REGISTRATION: ClinicalTrials.gov Registry: NCT04922502.https://classic. CLINICALTRIALS: gov/ct2/show/NCT04922502.