Department of Orthodontics and Dentofacial Orthopedics, Dental School/Medical Faculty, University of Bern, Switzerland.
Eur J Orthod. 2011 Dec;33(6):684-90. doi: 10.1093/ejo/cjq141. Epub 2011 Feb 14.
Randomization is a key step in reducing selection bias during the treatment allocation phase in randomized clinical trials. The process of randomization follows specific steps, which include generation of the randomization list, allocation concealment, and implementation of randomization. The phenomenon in the dental and orthodontic literature of characterizing treatment allocation as random is frequent; however, often the randomization procedures followed are not appropriate. Randomization methods assign, at random, treatment to the trial arms without foreknowledge of allocation by either the participants or the investigators thus reducing selection bias. Randomization entails generation of random allocation, allocation concealment, and the actual methodology of implementing treatment allocation randomly and unpredictably. Most popular randomization methods include some form of restricted and/or stratified randomization. This article introduces the reasons, which make randomization an integral part of solid clinical trial methodology, and presents the main randomization schemes applicable to clinical trials in orthodontics.
随机化是在随机临床试验的治疗分配阶段减少选择偏差的关键步骤。随机化过程遵循特定的步骤，包括随机数列表的生成、分配隐藏和随机化的实施。在牙科和正畸文献中，将治疗分配描述为随机的现象很常见；然而，所遵循的随机化程序往往并不合适。随机化方法随机地将治疗分配给试验组，参与者和研究者都不知道分配情况，从而减少选择偏差。随机化需要生成随机分配、分配隐藏以及随机和不可预测地实施治疗分配的实际方法。最流行的随机化方法包括某种形式的限制和/或分层随机化。本文介绍了使随机化成为可靠临床试验方法学不可或缺的一部分的原因，并介绍了适用于正畸临床试验的主要随机化方案。
