是否从试点研究进展到最终试验通常以预先指定的定量进展标准为指导，并具有三种可能的结果。尽管这些进展标准的选择将有助于确定试点试验的统计特性，但缺乏研究如何确定这些进展标准或试点样本量。我们回顾了最初在第二阶段肿瘤学设置并将其扩展到外部试点的情况，提出了基于单变量假设检验和频率错误率控制的统一框架。我们将此框架应用于示例，并与简单的二结果替代方案进行比较。我们发现三结果设计可以在试点环境中使用，尽管它们通常并不比简单的二结果替代方案更有效。我们表明，三结果设计可以帮助其他信息来源或其他利益相关者在出现临界结果时纳入进展决策，但这将以比两种结果情况更大的试点样本量为代价。我们还表明，三结果设计可用于在开始最终试验之前对干预或试验设计进行调整，前提是可以在试点设计阶段准确预测调整的效果。提供了一个 R 包来优化进展标准和试点样本量。所提出的三结果框架提供了一种优化试点进展标准和样本量的方法，从而产生所需的操作特性。无论试点试验后是否预期进行调整，它都可以应用，但通常会导致比更简单的两种结果替代方案更大的样本量要求。© 2024。作者。

Whether or not to progress from a pilot study to a definitive trial is often guided by pre-specified quantitative progression criteria with three possible outcomes. Although the choice of these progression criteria will help to determine the statistical properties of the pilot trial, there is a lack of research examining how they, or the pilot sample size, should be determined.We review three-outcome trial designs originally proposed in the phase II oncology setting and extend these to the case of external pilots, proposing a unified framework based on univariate hypothesis tests and the control of frequentist error rates. We apply this framework to an example and compare against a simple two-outcome alternative.We find that three-outcome designs can be used in the pilot setting, although they are not generally more efficient than simpler two-outcome alternatives. We show that three-outcome designs can help allow for other sources of information or other stakeholders to feed into progression decisions in the event of a borderline result, but this will come at the cost of a larger pilot sample size than the two-outcome case. We also show that three-outcome designs can be used to allow adjustments to be made to the intervention or trial design before commencing the definitive trial, providing the effect of the adjustment can be accurately predicted at the pilot design stage. An R package, tout, is provided to optimise progression criteria and pilot sample size.The proposed three-outcome framework provides a way to optimise pilot trial progression criteria and sample size in a way that leads to desired operating characteristics. It can be applied whether or not an adjustment following the pilot trial is anticipated, but will generally lead to larger sample size requirements than simpler two-outcome alternatives.© 2024. The Author(s).