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. 2023 Oct;27(18):1–120. doi: 10.3310/CPMS3211

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

Chris Hollis, Charlotte L Hall, Kareem Khan, Marie Le Novere, Louise Marston, Rebecca Jones, Rachael Hunter, Beverley J Brown, Charlotte Sanderson, Per Andrén, Sophie D Bennett, Liam R Chamberlain, E Bethan Davies, Amber Evans, Natalia Kouzoupi, Caitlin McKenzie, Isobel Heyman, Joseph Kilgariff, Cristine Glazebrook, David Mataix-Cols, Eva Serlachius, Elizabeth Murray, Tara Murphy
PMCID: PMC10641713  PMID: 37924247

Abstract

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 (95% confidence interval -£59 to £1384), 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. 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.

FUTURE WORK

Future work should compare online to face-to-face therapy and explore how to embed the intervention in clinical practice.

TRIAL REGISTRATION

This trial is registered as ISRCTN70758207; ClinicalTrials.gov (NCT03483493). The trial is now complete.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health and Technology Assessment programme (project number 16/19/02) and will be published in full in Health and Technology Assessment; Vol. 27, No. 18. See the NIHR Journals Library website for further project information.

Plain language summary

It can be difficult for children and young people with tics to access therapy. This is because there are not enough trained tic therapists. Online remote behavioural intervention for tics was a clinical trial to see whether an online platform that delivered two different types of interventions could help tics. One intervention focused on techniques to control tics; this type of therapy is called exposure and response prevention. The other intervention was psychoeducation, where participants learned about the nature of tics but not how to control them. The online remote behavioural intervention for tics interventions also involved help from a therapist and support from a parent. Participants were aged 9–17 years with Tourette syndrome/chronic tic disorder and were recruited from 16 clinics, two study sites (Nottingham and London) or via online self-referral. All individuals who were eligible for the online remote behavioural intervention for tics trial were randomised in a 50/50 split by researchers who were unaware of which treatment was being given. Participants received either 10 weeks of online exposure and response prevention or 10 weeks of online psychoeducation. A total of 224 children and young people participated: 112 allocated to exposure and response prevention and 112 to psychoeducation. Tics decreased more in the exposure and response prevention group (16% reduction) than in the psychoeducation group (6% reduction) 3 months after treatment. This difference is considered a clinically important difference in tic reduction. The treatment continued to have a positive effect on tic symptoms at 6, 12 and 18 months, showing that the effects are durable. This was achieved with minimal therapist involvement. The cost of online exposure and response prevention to treat young people with tics within this study was less when compared to the cost of face-to-face therapy. The results show that exposure and response prevention is an effective behavioural therapy for tics in this specific patient group. Delivering exposure and response prevention online with minimal therapist contact can be a successful and cost-effective treatment to improve access to behavioural therapy.

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