Worry-specific versus self-tailored internet-based treatments for generalized anxiety disorder, with scheduled support or support on demand: A pilot factorial design trial

Studies suggest that internet-delivered cognitive behaviour therapy (ICBT) can be effective when treating generalized anxiety disorder (GAD). This pilot factorial design study examined the effects of two types of ICBT (worry-specific and self-tailored treatment), and two support types (scheduled weekly support and support on demand), on measures of worry, anxiety, and depressive symptoms. Participants (N = 85) were randomized into four treatment groups. Post-treatment measures were completed by 76.5% after eight weeks (n = 65). Intention to treat analysis showed significant improvements, with moderate to large within-group effects on the primary outcome measure, Penn State Worry Questionnaire (Cohen's d = 0.77–1.43). Minor to large effects on the secondary measures were found in all groups (Cohen's d = 0.13–1.66). No significant differences in outcome measures were found between the groups. Receiving scheduled support and self-tailored treatment was rated as more positive than receiving support on demand and the worry-specific program. A limitation is the low number of participants. The pilot results suggest that GAD can be treated with both worry-specific and self-tailored treatments, and that ICBT can be supported both with scheduled and support on demand.