Randomised controlled trials (RCTs) of adults aged 17 to 64 years with anxiety, depression, or both, were eligible for inclusion if they compared guided self-help interventions against unguided self-help, usual psychological treatment or waiting list controls. The definition of anxiety or depression had to be based on a structured clinical interview or validated assessment scale. To be included, trials had to report clinical effectiveness as an outcome, measured by validated observer or self-report tools for anxiety or depression. Guided self-help was defined as an individual’s access to CBT self-help materials, with active guidance from a professional or paraprofessional therapist for at least 30 minutes and no more than three hours. The therapist's involvement had to be more than reminders or assessment monitoring. Trials with less than one month of follow-up were not eligible.
In the included trials, recruitment was either through media advertisements or clinical referral. The mean age of participants ranged from 32.4 to 45 years, and the percentage of females ranged from 59 to 84. Participants had one or more diagnosis of: depression, panic disorder, social phobia, other phobias, and general anxiety. Four trials included patients with severe depression. Few details of the interventions were given, but they included internet or face-to-face guidance, from a general practitioner or nurse. The duration of guidance ranged from 60 to 180 minutes. The control patients were either on a waiting list or received discussion group support, usual care, relaxation, or internet-guided minimal CBT. Follow-up ranged from one month to one year.
The authors did not state how many reviewers selected trials for inclusion.