对照是临床科研设计的基本原则之一。在临床科学研究的工作中,有的研究项目被试因素虽是已知,但却无法被研究者所能控制,有的影响因素尚未被人们所认识,处理这些问题则需运用平行对照的方法加以解决。以临床研究而言,研究的受试对象就是病例。受试病例采用对照的方法,一般是将受试病例分为实验组与对照组两个部份,分 Control is one of the basic principles of clinical research design. In the work of clinical science research, although some research project participants are known factors, but can not be controlled by the researchers, and some influencing factors have not yet been recognized, to deal with these problems need to use the method of parallel control To be solved. In clinical research, the subjects of the study are the cases. The test cases using the control method, the test cases are generally divided into experimental group and control group in two parts, points