[A brief introduction to Appraisal of Guidelines for Research and Evaluation II].

Clinical practice guidelines play an important role in practitioner and patient decisions regarding appropriate clinical health care and in health policy formation. In the guideline development process, inappropriate methodologies and development strategies significantly influence the quality of guidelines; therefore, research and evaluation of guidelines have great significance. The original Appraisal of Guidelines for Research and Evaluation (AGREE) instrument was published in 2003 by a group of international guideline developers and researchers. AGREE has important significance for the quality guarantee and successful implementation of guidelines, and has extensively achieved endorsement since 2003. In 2009, The AGREE Collaboration has developed the AGREE II by refining the original AGREE instrument. At present, the AGREE II has already replaced the original AGREE instrument; however, related introduction regarding AGREE II has not been found in China. The authors of this article briefly introduce the AGREE II, and believe that it will add value to research and evaluation of the guidelines.