Ethics, methodology and the use of placebo controls in surgical trials.

There is an emergent view among North American researchers and bioethicists that not only is the use of sham surgery ethical, but that it should also be mandatory when conducting trials to evaluate surgical procedures such as neural grafting. This view is based on erroneous assumptions concerning the magnitude of the placebo effects associated with surgery. A detailed analysis of four recent clinical trials failed to provide consistent evidence for pronounced and long term improvements in sham operated patients. There was no evidence that the results of the placebo control groups were necessary for identifying unsafe and ineffectual surgical procedures. We contend that the advancement of clinical science and the protection of individual patients are best guaranteed by adopting the principles of evidence-based medicine.