I want to start with a few definitions and give you some background to the field.  I’m talking about a series of diverse medical and health care practices that share the fact that they are outside the realm of conventional medicine and are yet to be validated by scientific methods.  These include things that we call complementary because people choose to use them in addition to the kinds of practices that we have long sought to develop and champion here at the NIH.  And alternative practices are ones that people choose in place of those remedies, however effective they are.

什么是补充与替代医学（CAM）？

CAM是指业已经过科学方法加以证实的传统医学领域之外的医学和健康护理实践。

补充：协同传统实践

替代：取代传统实践