WASHINGTON --- Psychologist Irving Kirsch and his co-authors analyzed all of the data submitted to the U.S. Food and Drug Administration for approval of the six most widely prescribed antidepressants between 1987 and 1999. They found that approximately 80% of the response to the medications was duplicated in placebo control groups. They believe the difference between the patient's response to medication and response to placebo was small enough to be considered clinically meaningless. However, Kirsch et al. speculate that the true drug effect may be more than the difference between the medication and the placebo.
How effective are antidepressants? Kirsch et al.'s thesis is that we really don't know. They submit that either the effects of the medications are very small or being missed by current effectiveness measurements due potentially to the way in which the drug trials are conducted.
In commentaries on Kirsch's article other researchers generally agree with his findings but disagree as to why they are occurring. Some argue that antidepressants are being overmarketed and overprescribed. Others suspect the way the drugs are evaluated lead to the finding suggesting that the drug trial procedures themselves increase the placebo response or miss important subgroups of patients who may be best treated by medications. All conclude that better ways to measure the effectiveness of numerous depression treatments including medications, psychosocial factors and psychotherapy are needed.
Article: "An analysis of Antidepressant Medication Data Submitted to the FDA,". Irving Kirsch, University of Connecticut; Thomas J. Moore, George Washington University; Alan Scoboria and Sarah S. Nicholls, University of Connecticut. Prevention and Treatment, American Psychological Association.
Full text available from APA Public Affairs Office or after 7/8/02 at APA Journals/Prevention and Treatment.
Author Contacts:
Lead Authors:
Irving Kirsch, PhD, University of Connecticut
In Italy - 39 055 631783
Thomas Moore, PhD, George Washington University
(202) 530-2348
David Antonuccio, PhD, University of Nevada School of Medicine
775 784-6388, ex. 229
Steven Hollon, PhD, Vanderbilt University
(O) 615 322-3369
(H) 615 373-2422
Michael Thase, MD, University of Pittsburgh Medical Center
412 624-5070
Roger P. Greenberg, PhD, SUNY - Update Medical University
(O) 315 464-3120
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