OBJECTIVES: In the UK, around 93,000 children and young people (CYP) experience specific phobias with a substantial impact on daily life. The current gold-standard treatment (multi-session cognitive behavioural therapy - CBT) is effective at reducing specific phobia severity; however, it is time consuming, requires specialist therapists, and can be costly with limited availability. It has been found one-session treatment (OST), a briefer variant of CBT, offers similar effectiveness. The aim of this study was to assess the cost-effectiveness of OST compared to multi-session CBT for CYP with specific phobias through ASPECT, a two-arm, pragmatic, multi-centre, non-inferiority randomised controlled trial.

METHODS: CYP aged 7 to 16 years with specific phobias were recruited nationally via the Health and Social Care pathways, randomised to the intervention group and control groups, and analysed (n=267). Resource use based on NHS and personal social services perspective and quality adjusted life years (QALYs) measured by EQ-5D-Y were collected at baseline and at six-month follow-up. Incremental cost-effectiveness ratio (ICER) was calculated, and non-parametric bootstrapping was conducted to capture uncertainty around the ICER estimates. The results were presented on a cost-effectiveness acceptability curve (CEAC). A set of sensitivity analyses (including taking a societal perspective) were conducted to assess the robustness of the primary findings.

RESULTS: After adjustment and bootstrapping, on average CYP in the OST group incurred less costs (incremental cost was -£302.96 (95% CI -£598.86 to -£28.61)) and maintained similar improvement in QALYs (gained 0.002 (95% CI −0.004 to 0.008)). The CEAC shows the probability of OST being cost-effective was over 95% across all the WTP thresholds. Results of a set of sensitivity analyses were consistent with the primary outcomes.

CONCLUSIONS: Compared to CBT, OST produced a reduction in costs and maintained similar improvement in QALYs. Results from both primary and sensitivity analyses suggested that OST was highly likely to be cost saving.