Interpreting antidepressant clinical trials.

BACKGROUND

Psychiatrists and other clinicians make decisions about antidepressant medications with little understanding on how to interpret the research literature.

METHODS

Pertinent clinical literature is reviewed.

RESULTS

The author reviews levels of evidence, study design, statistical significance, p values, defining outcomes, drop outs, and basic analytic strategies such as last observation carried forward and mixed-effects model repeated measures. Several recent clinical trials are dissected to illustrate these concepts.

CONCLUSIONS

Clinicians need to develop greater sophistication at interpreting research findings. No single study is definitive, and comparative antidepressant trials suffer from low statistical power.