Transdiagnostic internet treatment for anxiety and depression: A randomised controlled trial

► We compare the efficacy of transdiagnostic internet CBT vs. waitlist control. ► We examine changes in diagnosis and symptoms at post-treatment and at follow-up. ► Changes in the treatment group were superior to controls on all generic measures. ► Participants rated the procedure as highly acceptable. ► Transdiagnostic treatments could be administered via the internet.