Treating young adult generalized anxiety disorder with text-message delivered cognitive behavioral therapy: A randomized clinical trial testing efficacy and clinical mechanisms.

Approximately one in five (19.5 %) young adults have experienced generalized anxiety disorder (GAD) in the past year. Compared with other age groups, they are least likely to receive mental health treatment despite reporting greater need for these services. To address these issues, we conducted a randomized clinical trial with 102 young adults using an 8-week, automated text-message delivered cognitive behavioral therapy (CBT-txt-A) to treat GAD. We examined treatment engagement, tested treatment efficacy, and tested 3 clinical mechanisms of change. Participants were from 33 states, recruited from Instagram and Facebook who presented with at least moderate GAD symptomatology. Assessments occurred at baseline prior to randomization and at 1, 2, and 3 months after enrollment. The primary outcome, severity of GAD symptoms, was assessed using the GAD-7 measure. Behavioral activation, perseverative thinking, and cognitive distortions were hypothesized clinical mechanisms. Participants were randomized to CBT-txt-A or a waitlist control condition. Results indicated that participants in the CBT-txt-A group significantly reduced their GAD symptoms over time compared to the control condition, producing a large effect size (Cohen d = 0.83). One quarter of the treatment group moved into the high-end state functioning level, representing no or minimal GAD symptoms, compared to 5.5 % of the controls. Mediation analyses indicated that CBT-txt-A increased behavioral activation, and reduced perseverative thinking and cognitive distortion, at 2 months, which in turn, was then associated with reductions in GAD symptoms at 3 months. Results provide evidence for the efficacy of CBT-txt-A in reducing GAD symptoms through three hypothesized clinical mechanisms.