1　定群研究定群研究实质上是非对照性前瞻研究 ,这种研究可以保留详细的数据资料并对其进行分析以评价针灸的效果。定群研究的优势在于可以使研究人员设计连贯紧凑的基本资料 ,并将其作为开展详细临床实验的基础。然而 ,时常所见 ,此类研究的方案设计不当 ,其数据采集也不全面 1 Cluster Study Cluster study is essentially an uncontrolled prospective study that retains detailed data and analyzes it to evaluate the effectiveness of acupuncture. The advantage of cohort studies is that they allow researchers to design coherent and compact sets of basic information as a basis for conducting detailed clinical trials. However, as often seen, the design of such studies is not properly designed and its data collection is not comprehensive