Online remote behavioural intervention for tics in 9-to 17-year-olds: the ORBIT RCT with embedded process and economic evaluation

Background: Behavioural therapy for tics is difficult to access, and little is known about its effectiveness when delivered online.Objective: To investigate the clinical and cost-effectiveness of an online-delivered, therapist- and parent-supported therapy for young people with tic disorders.Design: Single-blind, parallel-group, randomised controlled trial, with 3-month (primary end point) and 6-month post-randomisation follow-up. Participants were individually randomised (1 : 1), using on online system, with block randomisations, stratified by site. Naturalistic follow-up was conducted at 12 and 18 months post-randomisation when participants were free to access non-trial interventions. A subset of participants participated in a process evaluation.Setting: Two hospitals (London and Nottingham) in England also accepting referrals from patient identification centres and online self-referrals.Participants: Children aged 9-17 years (1) with Tourette syndrome or chronic tic disorder, (2) with a Yale Global Tic Severity Scale-total tic severity score of 15 or more (or > 10 with only motor or vocal tics) and (3) having not received behavioural therapy for tics in the past 12 months or started/stopped medication for tics within the past 2 months.Interventions: Either 10 weeks of online, remotely delivered, therapist-supported exposure and response prevention therapy (intervention group) or online psychoeducation (control).Outcome: Primary outcome: Yale Global Tic Severity Scale-total tic severity score 3 months post-randomisation; analysis done in all randomised patients for whom data were available. Secondary outcomes included low mood, anxiety, treatment satisfaction and health resource use. Quality-adjusted life-years are derived from parent-completed quality-of-life measures. All trial staff, statisticians and the chief investigator were masked to group allocation.Results: Two hundred and twenty-four participants were randomised to the intervention (n = 112) or control (n = 112) group. Participants were mostly male (n = 177; 79%), with a mean age of 12 years. At 3 months the estimated mean difference in Yale Global Tic Severity Scale-total tic severity score between the groups adjusted for baseline and site was -2.29 points (95% confidence interval -3.86 to -0.71) in favour of therapy (effect size -0.31, 95% confidence interval -0.52 to -0.10). This effect was sustained throughout to the final follow-up at 18 months (-2.01 points, 95% confidence interval -3.86 to -0.15; effect size -0.27, 95% confidence interval -0.52 to -0.02). At 18 months the mean incremental cost per participant of the intervention compared to the control was 662 pound (95% confidence interval -59 pound to 1384) pound, with a mean incremental quality-adjusted life-year of 0.040 (95% confidence interval -0.004 to 0.083) per participant. The mean incremental cost per quality-adjusted life-year gained was 16,708 pound. The intervention was acceptable and delivered with high fidelity. Parental engagement predicted child engagement and more positive clinical outcomes.Harms: Two serious, unrelated adverse events occurred in the control group.Limitations: We cannot separate the effects of digital online delivery and the therapy itself. The sample was predominately white and British, limiting generalisability. The design did not compare to face-to-face services.Conclusion: Online, therapist-supported behavioural therapy for young people with tic disorders is clinically and cost-effective in reducing tics, with durable benefits extending up to 18 months.