The various research methodologies outlined in these guidelines can all contribute some information in the context of research conducted for any purpose. Of all the research methodologies outlined, the randomized controlled (clinical) trials (RCTs) are considered to be the most sophisticated and in many ways have become the “gold standard” for clinical trials in modem clinical research.

There are, however, significant limitations to this approach of RCTs. First, they are often costly, cumbersome, and only incremental answers can be obtained. This is a major drawback in the context of evaluation of whole medical systems such as herbal medicine or acupuncture.

In addition, the RCTs, by definition, eliminate the possible influence of a patient’s preference and patient/therapist interaction on the outcome of the treatment. These limitations may be at least partially compensated by carefully designed retrospective and prospective outcome research as described under “Acupuncture epidemiology”. Properly planned prospective research is usually superior to retrospective research.

Thus, in the context of acupuncture research, an RCT could be indicated where the purpose of a study is to help improve acupuncture practice, for example, to determine which point combinations are most suited to treat a given condition.

In contrast, acupuncture epidemiology (outcome research) would be indicated where the purpose of research is to evaluate the preventive value of acupuncture or guide patients’ choice and health policy.

Finally, while clinical audit and single case studies (n of 1 trial) have a number of inherent limitations, they would be ideal to spur interest in acupuncture research among all researchers and practitioners. Such interest could result in valuable preliminary information generated by an increased positive and critical attitude to ancient traditional statements.