Does internet-based cognitive behaviour therapy reduce healthcare costs and resource use in treatment of social anxiety disorder? A cost-minimisation analysis conducted alongside a randomised controlled trial

OBJECTIVES Social anxiety disorder (SAD) can be effectively treated with internet-delivered cognitive behavioural therapy (ICBT), but studies on long-term cost minimisation from a healthcare provider perspective in comparison to an evidence-based control treatment of therapeutic equivalence are lacking. The objective of the study was to determine whether ICBT reduces healthcare costs and use of healthcare resources compared with cognitive behavioural group therapy (CBGT). DESIGN A cost-minimisation study alongside a randomised controlled trial where participants (n=126) with SAD were randomised to ICBT or to CBGT. Costs measured from a healthcare provider perspective were estimated using time-driven activity-based costing alongside health status over 4 years from baseline measured with EQ-5D. SETTING A psychiatric outpatient clinic in Stockholm, Sweden. PARTICIPANTS Participants were 126 individuals with SAD. PRIMARY OUTCOME MEASURES Changes in EQ-5D and costs. INTERVENTIONS Participants received either CBGT or ICBT for a duration of 15 weeks. RESULTS ICBT minimised healthcare costs and demonstrated health improvements within the non-inferiority margin. Assuming a practical work capacity for personnel varying between 100%, 80% and 50% of theoretical full capacity, the cost for ICBT varied in the range between 400€, 463€ and 654 €, while the cost for CBGT varied between 699€, 806€ and 1134€. Within-group effect size was -0.36 (95% CI -0.70 to -0.01) for ICBT and -0.25 (95% CI -0.60 to 0.10) for CBGT. Mean use of effective psychologist time in ICBT was 189.60 (SD=53.77) minutes compared with 499.78 (SD=30.91) in the CBGT group. CONCLUSIONS In treatment of SAD, ICBT is equally effective but is associated with more efficient staff utilisation and less costs compared with CBGT. From a healthcare provider perspective, ICBT is an advantageous treatment option. TRIAL REGISTRATION NUMBER