Critical appraisal of clinical studies in Chinese herbal medicine

The use of complementary and alternative medicine (CAM) is currently widespread and appears to be growing. As an increasing proportion of the population turns to CAM therapies, whether singly or in combination with allopathic medicine, the need for quality research in this area is reinforced. Much of this research consists of clinical studies aimed primarily at clinicians, yet challenges arising from poor methodological quality will occur when interpreting study findings and their implications. For clinicians to be effective consumers of the scientific literature, familiarization with the principles of evidence-based medicine (EBM) is essential. The goal of this review is to introduce clinicians to the concept of critical appraisal of clinical studies and foster critical thinking when reading research articles in order to best evaluate and incorporate study findings into their daily practice. Topics discussed in this article include: (1) fundamentals of EBM; (2) types of clinical studies; (3) hierarchy of evidence; (4) Consolidated Standard of Randomized Trials (CONSORT) statement to evaluate the quality of reporting in randomized controlled trials (RCTs); (5) methodologic quality rating scales for RCTs; and (6) issues specific to evaluating studies of Chinese herbal medicine.