[img_inline align=”right” src=”http://padnws01.mcmaster.ca/images/Guyatt.Gordon.jpg” caption=”Gordon Guyatt”]Physicians should be wary of overly optimistic results from randomized clinical trials that are stopped early because of apparent benefits, says a study led by McMaster University researchers.

A review article in the November 2 issue of the Journal of the American Medical Association (JAMA) states that although the trials stopped early are becoming more common and gaining more publicity, they often show implausibly large treatment effects and fail to report the specifics on why the trial was stopped.

The JAMA article is based on a systematic review of 143 randomized clinical trials that were stopped early for benefit over a 14-year period, said Gordon Guyatt, corresponding author of the study and a professor in the departments of medicine and clinical epidemiology and biostatistics for the Michael G. DeGroote School of Medicine.

“We found that these trials are becoming more common, most are published in top, high-profile journals, and many fail to report crucial aspects of their methods,” he said. “Trials stopped early for benefit are likely leading to falsely optimistic estimates of treatment effect, and misleading physicians and patients.”

The study noted that particularly in smaller trials, there is a greater likelihood of exaggerated results of the treatment being tested. The clinical trials examined in the study were typically industry-funded drug trials in cardiology, cancer and human immunodeficiency virus/AIDS. The findings suggest clinicians should view the results of such trials with skepticism.