Transdiagnostic internet treatment for anxiety and depression

Anxiety and depression are common, chronic, disabling and frequently comorbid, but many people experience barriers accessing treatment. Internet-delivered psychological treatments (iPT) have considerable potential to increase access, while transdiagnostic (TD) interventions, which aim to simultaneously treat multiple disorders, represent an emerging approach that may facilitate the treatment of comorbidity. The present paper describes a conceptual and pragmatic rationale for combining iPT and TD approaches. It also describes the authors' experiences in developing and evaluating TD iPT protocols for anxiety and depression. The results of 4 randomised controlled trials and one open trial (N = 572) are reviewed. The results of these trials are encouraging and indicate TD iPT can significantly reduce symptoms of both principal and comorbid disorders. However, independent replication of the existing findings is required and many outstanding questions remain. We watch with interest how further conceptual and technological developments influence the content and delivery of these interventions.