Antidepressants could be little better than a placebo for all but the most severe depression. Researchers from the University of Pennsylvania in Philadelphia carried out a data analysis combining information from six different trials covering a total of 718 participants. They found that true advantages of antidepressants over placebos were 'non-existent to negligible' among depressed patients with mild, moderate and even severe symptoms. However, the drugs were very effective among patients with severe depression. The authors of the study pointed out that many studies used by drug companies to publicise the benefits of antidepressants only included severely-depressed people as participants.
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