An international study of nearly 100 clinical trials that were stopped early due to positive treatment effects has found that many of those effects were exaggerated. The authors of the study — published in the current issue of the Journal of the American Medical Association — recommend that researchers resist pressures to end clinical trials early and continue trials for longer periods before even considering premature termination.
“Our research shows that in most cases early stopping of clinical trials resulted in misleading estimates of treatment effects. These misleading estimates are likely to result in misguided decisions about the trade-off between risks and benefits of a therapy”
“Our research shows that in most cases early stopping of clinical trials resulted in misleading estimates of treatment effects. These misleading estimates are likely to result in misguided decisions about the trade-off between risks and benefits of a therapy,” says Victor Montori, M.D., Mayo Clinic endocrinologist and corresponding author of the study. “On average, treatments with no effect would show a reduction in relative risk of almost 30 percent in stopped early trials. Treatments with a true relative risk reduction of 20 percent would show a reduction of over 40 percent.”