Antidepressants are far less effective than doctors and the public may have been led to believe, a new study has claimed.
Eighty – eight per cent of clinical trials that showed the drugs were less than effective either were not published in medical journals or were presented as positive findings, according to the study in the New England Journal of Medicine.
The researchers examined the studies that drug companies submitted to the Food and Drug Administration in the United States when they were seeking regulatory approval for 12 antidepressants.
The drugs were all approved between 1981 and 2004, and are now widely prescribed.
It was found that all but one of the 38 positive studies given to the FDA were published, but most of the negative studies were not published.
A doctor reading the medical journals would think that individual antidepressants were between 11- and 69-per-cent more effective than they really are, according to Prof Erick Turner, of Oregon Health and Science University, who is lead author on the paper.
He said it is not that antidepressants do not work, but that their effectiveness has been exaggerated.