Dekkers Olaf M
Leids Universitair Medisch Centrum, afd. Klinische epidemiologie, Leiden, the Netherlands.
Ned Tijdschr Geneeskd. 2012;156(9):A4069.
Not all questions concerning therapeutic effects in medical research can be answered satisfactorily by standard trials. The stepped wedge cluster design is a special form of randomised study in which an intervention at group level is implemented in stages. The design can be used in situations where randomization at the patient level is inappropriate or impossible and where a stepped implementation of the experimental intervention is important for ethical, logistic or financial reasons. The time before the experimental intervention is introduced in a cluster is used as control period. The statistical analysis of cluster trials should account for the fact that individuals within clusters may show many similarities. Ethical aspects of stepped wedge design should be considered carefully, especially when obtaining individual informed consent is not possible.
并非医学研究中所有关于治疗效果的问题都能通过标准试验得到令人满意的答案。阶梯式楔形整群设计是一种特殊形式的随机研究，其中在群体层面的干预是分阶段实施的。该设计可用于患者层面的随机化不合适或不可能的情况，以及出于伦理、后勤或财务原因，实验性干预的分阶段实施很重要的情况。在一个整群中引入实验性干预之前的时间用作对照期。整群试验的统计分析应考虑到整群内个体可能表现出许多相似性这一事实。应仔细考虑阶梯式楔形设计的伦理问题，尤其是在无法获得个体知情同意的情况下。
