Presentation Master's Thesis- Niek Putter- Clinical Psychology

Generalised anxiety disorder (GAD) is common and distressing, while subthreshold GAD is even more common and also impairs functioning. Internet-delivered CBT (iCBT), including third-wave approaches, aims to reduce access barriers to face-to-face CBT while maintaining efficacy. We systematically reviewed randomised trials that included adults with a diagnosis of GAD and those with elevated anxiety symptoms above the cut-off (double checking each extraction). In total, 18 trials with 19 conditions and more than 1,500 participants were included. In addition to the main analysis, I performed subgroup and sensitivity analyses, bivariate and multivariate meta-regressions, assessed risk of bias and checked for publication bias. iCBT showed a clear moderate to large benefit over controls. By including both diagnosed and elevated symptom populations, the study adds to the literature by showing that iCBT is effective across a broader spectrum of generalised anxiety.