Most Trials in Clinical Practice Hold Up Over Time
According to a new paper in Family Practice, medical practice can often be undermined by later research, randomised trials relevant to primary care generally hold up over time.
Medical reversal describes a problem whereby new research causes doctors to stop using a popular medication, procedure or test based on previous evidence. Vinayak Prasad, associate professor at the University of California, San Francisco, had found that up to 46% of original studies on adopted medical practices led to a reversal or shift in evidence of effect.
Evidence-based medicine lets doctors be confident when their decisions are grounded in high quality research. But decisions supported by robust evidence from randomised controlled trials can be reversed. For example, although aspirin is prescribed commonly to prevent cardiovascular disease, new studies indicate this treatment is unlikely to be effective.
Researchers studied the extent to which evidence from randomised control trials relevant to primary care were contradicted in subsequent research. Examining 408 randomised controlled trials from 2002 to 2005 relevant to primary care, the researchers found that over 12-17 years of follow up time, there were just 35 occurrences of evidence reversal, or roughly two a year. About nine in ten of such randomised control trials were not reversed.
“Conclusions from randomised trials relevant to primary care that also meet criteria for validity are stable over time,” said study lead author Christian Ruchon.
Source: EurekAlert!
