Study designs of evaluations included in the review
Randomised controlled trials (RCTs), convenience sample studies and pre-test post-test studies were eligible for inclusion in the review; case studies were excluded. The included studies were RCTs, convenience sample studies and longitudinal studies.
Specific interventions included in the review
Studies that compared telephone-based interventions with a control or face-to-face interventions were eligible for inclusion. Studies that compared two telephone-based interventions without a suitable control group were excluded, as were studies that evaluated group therapy, teletherapy with visual aids, telephone-accessed computer systems or assessment tools delivered using the telephone. The included studies evaluated a variety of telephone-based interventions, including cognitive-behavioural therapy, problem-solving, behaviour monitoring and change, psycho-education, exposure therapy, and identification of goals and stressors. Some of the included studies also used antidepressant medication.
Participants included in the review
Studies of patients with mental illness were eligible for inclusion. Studies that focused on specific populations were excluded. The included studies were in patients with depression, anxiety disorders (including obsessive-compulsive disorder (OCD) and panic disorder), eating disorders (including binge eating disorders and bulimia nervosa), substance-use disorders and schizophrenia.
Outcomes assessed in the review
Studies that assessed outcomes not specifically related to mental illness were excluded. The included studies assessed a variety of measures including the Hamilton Rating Scale (HRS), Beck Depression Inventory (BDI), Hopkins Symptom Checklist Depression Scale (SCL), Centre for Epidemiologic Depression Scale, OCD symptom scores, Fear Questionnaire ratings, Anxiety Sensitivity Index, Eating Disorder Inventory, Body Mass Index, binge eating, vomiting, laxative abuse, remission behaviour, abstinence, re-hospitalisation, duration of readmission and community survival. Self-reported measures were also included.
How were decisions on the relevance of primary studies made?
The authors did not state how the papers were selected for the review, or how many reviewers performed the selection.