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July 11, 1977

Medical News

JAMA. 1977;238(2):107-115. doi:10.1001/jama.1977.03280020011001

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Review of clinical studies suggests many trials don't last long enough  If the result of a randomized, controlled clinical trial is published as negative, showing no difference between treatment and control groups, is this result always believable?The question has been examined by researchers at the Mount Sinai School of Medicine, New York, who reviewed 76 randomized, controlled clinical trials published between 1959 and 1976. The investigators in these projects viewed their results as negative or as yielding "no difference" between treatment and control groups (P>.05). But the Mount Sinai team has shown that based on the control rate of response in each study, the difference in response rate between treatment and control groups, and the number of patients studied, a majority of the trials had an unacceptably high probability of missing a true positive result if it indeed existed. The trials were terminated before they had ruled