Study designs of evaluations included in the review
Studies with a control group.
Specific interventions included in the review
Cognitive behavioural therapy (CBT) and pharmacologic treatments with control comparisons (no treatment, wait list, or pill or psychological placebo).
Cognitive behavioural treatments included: cognitive restructuring, situational and imaginal exposure, interoceptive exposure, systematic desensitization, relaxation training (with or without biofeedback), and/or anxiety management training. Pharmacologic treatments included all agents for GAD that have been approved or are commonly used for this indication in the United States.
The authors also assessed the effect of methodological factors on treatment efficacy (treatment length, attrition rates, type of control condition employed, use of independent assessors, format of results, and concurrent medication usage).
Participants included in the review
Patients being treated for generalised anxiety disorder. Participants had either to meet the American Psychiatric Association's (APA) Diagnostic and Statistical Manual of Mental Disorders (DSM; DSM-III, DSM-III-R, or DSM-IV) criteria for GAD, or clearly would have met them had they been applied. Women comprised 60.2% of the samples. Mean period of duration of GAD was 5.26 years (14 studies).
Most studies excluded patients with comorbid problems of alcohol or substance abuse, psychotic disorders, and suicidality. Patients with organic brain syndrome, epilepsy or disabling medical conditions were also typically excluded. Pharmacotherapy studies further excluded women who were pregnant and, frequently, subjects with a previous history of benzodiazepine intolerance.
Outcomes assessed in the review
Anxiety or worry (primary) and depression (secondary) outcomes were measured using self-report questionnaires and clinician-rated measures of change.
Measures of anxiety or worry included the Hamilton Anxiety Depression Scale (HAMD), Fear Questionnaire, State-Trait Anxiety Inventory, Zung Anxiety Scale, Covi Scale for Anxiety, Fear Survey Schedule, Cognitive-Somatic Anxiety Questionnaire, and the Pennsylvania State Worry Questionnaire. Measures of depression were assessed by the Beck Depression Inventory and the Hamilton Rating Scale for Depression.
How were decisions on the relevance of primary studies made?
The authors do not state how the papers were selected for the review, or how many of the reviewers performed the selection.