Posted by: Edzard Ernst25 August 2012
Patients often view treatments which are 'natural' as devoid of risks. It is obvious that this attitude is based on several misunderstandings: not all 'natural' treatments are truly natural and many are associated with harm.
Nevertheless, the myth that 'natural' equates harmless is relentlessly being promoted by the CAM industry. The evidence shows, they claim, that CAM causes less adverse effects (AEs) than conventional medicine. A recent article1by an international team of researchers throws some light on these issues.
They identified RCTs published in 2009 across 15 popular CAM interventions. The primary outcome measure was the adequacy of reporting of AEs. Some 205 trials were included in the review. Of these, 15% reported that no harms were observed during the trial period. Of the remaining 174 trials reporting any safety information, only 21% had adequate safety reporting.
This analysis highlights the fact that the important issue of safety is being neglected in RCTs of CAM. This violates basic rues of medical publishing. More importantly, over time, it might have created a false positive picture about the risks associated with CAM. If we do not report adverse effects, we will not know about them. And if we don’t know, our assumption of relative safety could be wrong.
Professor Edzard Ernst is professor of complementary medicine at the Peninsula Medical School, University of Exeter
1. Turner LA, Singh K, Garritty C et al. An evaluation of the completeness of safety reporting in reports of complementary and alternative medicine trials. BMC Compl Alt Med 2011:11-67.