临床治疗试验按对照设立的不同 ,分为下列几种研究方法 :(1)随机对照试验 :是将研究对象按随机化的方法分为试验组与对照组 ,以保证两组的可比性 ,然后 ,试验组给予治疗措施 ,对照组不给予欲评价的措施 ,前瞻性观察两组转归结局的差别。(2 )序贯试验 :序贯试验在试验前不规定样 The clinical trials are divided into the following several research methods: (1) randomized controlled trials: the research object is randomized into experimental group and control group to ensure the comparability of the two groups, and then , The experimental group given treatment measures, the control group did not give the measure to be evaluated, the prospective observation of the difference between the outcome of the two groups. (2) Sequential test: Sequential test is not specified before test