Comprehensive Clinical Trials Unit, University College London, London, UK.
Insitro, South San Francisco, California, USA.
Stat Med. 2022 Sep 10;41(20):4022-4033. doi: 10.1002/sim.9490. Epub 2022 Jun 10.
Selection trials are used to compare potentially active experimental treatments without a control arm. While sample size calculation methods exist for binary endpoints, no such methods are available for time-to-event endpoints, even though these are ubiquitous in clinical trials. Recent selection trials have begun using progression-free survival as their primary endpoint, but have dichotomized it at a specific time point for sample size calculation and analysis. This changes the clinical question and may reduce power to detect a difference between the arms. In this article, we develop the theory for sample size calculation in selection trials where the time-to-event endpoint is assumed to follow an exponential or Weilbull distribution. We provide a free web application for sample size calculation, as well as an R package, that researchers can use in the design of their studies.
选择试验用于比较没有对照臂的潜在有效实验治疗方法。虽然已经存在用于二分类结局的样本量计算方法，但对于生存时间结局，即使这些方法在临床试验中普遍存在，也没有这样的方法。最近的选择试验开始将无进展生存期作为主要终点，但为了样本量计算和分析，将其在特定时间点二分法化。这改变了临床问题，并且可能会降低检测臂间差异的功效。在本文中，我们为选择试验中的样本量计算开发了理论，其中假设生存时间结局遵循指数或威布尔分布。我们提供了一个免费的网络应用程序和一个 R 包，研究人员可以在研究设计中使用这些程序来进行样本量计算。
