Study designs of evaluations included in the review
Studies were included if they were randomised controlled trials (RCTs), comparing a newer antidepressant with either, another newer antidepressant, an older antidepressant, a placebo, or a psychosocial intervention. Studies had to have had an active intervention period of at least 6 weeks.
Specific interventions included in the review
Thirty-two specific agents from nine classes of antidepressants, i.e selective serotonin re-uptake inhibitors (SSRIs), selective norepinephrine re-uptake inhibitors, norepinephrine re-uptake inhibitors, reversible inhibitors of monoamine oxidase A, 5-HT2-receptor antagonists, 5-HT1A-receptor agonists, Gabamimetics, dopamine antagonists, and dopamine re-uptake inhibitors. Herbal remedies and other miscellaneous agents were also included. Various dose regimens were used.
Participants included in the review
Adult patients in the primary care setting requiring treatment for depression. Patients included those with mild, moderate or major depression, endogenous depression, depression requiring treatment, dysthimia, or mixed anxiety depression.
Outcomes assessed in the review
All studies had to have measured a clinical outcome such as depression, functional status or quality of life. The primary outcome measure was response rate (defined as the proportion of patients having a 50% or greater improvement in symptoms as assessed by a depression symptoms rating scale) or a rating of much or very much improved, as assessed by a global assessment method.
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.