新药临床研究须遵循随机原则，将受试者分配到各实验组。所谓盲法，就是受试者不知道被分到哪一组。盲法设计有单盲及双盲两种，前者是患者不知自己所用何药，后者是患者和医师均不知所用何药。应首选双盲，特殊情况可只设单盲，如供试品有特殊气味难以设盲，厂家可以申诉理由? New drug clinical research should follow the random principle, the subjects assigned to the experimental group. The so-called blind method is that subjects do not know which group was assigned. Blind design has single-blind and double-blind two, the former is the patient do not know what medicine they used, the latter is the patient and the physician are not aware of what medicine. Should be the preferred double-blind, special circumstances can be set only single blind, such as the test product has a special smell difficult to blind, manufacturers can appeal reason?