Evaluation of an online-based self-help program for patients with generalized anxiety disorder - a randomized controlled trial

Objectives: This study aimed to evaluate the effects of an online self-help intervention for generalized anxiety disorder (GAD). Our primary outcomes were reductions in generalized anxiety symptoms, measured using the GAD-7 (Spitzer et al., 2006), and improvements in well-being based on the WHO-5 (Topp et al., 2015). Methods: A total of 156 German-speaking patients aged 18 to 65 with a diagnosis of GAD and internet access were included in this randomized controlled trial. The intervention group (N = 78) received access to a 12-week online self-help program, while the waitlist control group (N = 78) received access only after the 12-week waiting period. Results: The intervention group showed a significant improvement in generalized anxiety symptoms compared to the control group (t(df=123.73) = -4.52, p < .001) with a medium to large effect size (d = -0.88, 95%-CI: -1.26; -0.50). Additionally, the intervention group demonstrated a significant increase in quality of life compared to the control group (t(df=87,86) = 3.48, p < .001), with a moderate to large effect size (d = 0.62, 95% CI: 0.27; 0.98). However, no significant effects were observed for secondary outcomes of functional impairments, work productivity, mental health literacy, and healthcare demands. For exploratory outcomes, improvement was found for anxiety and worry symptoms. Conclusions: These findings suggest that an online-based self-help intervention effectively reduces core GAD symptoms and improves overall quality of life. Future research should explore the long-term effects of this intervention and investigate potential mechanisms underlying its effectiveness.