AI 中文总结
针对儿童青光眼前瞻性随机临床试验的需求，开发了基于配对二元主要与短期替代终点的McNemar检验盲法样本量重新估计策略，该方法可保持I类错误率并达到目标功效，还能处理中期仅获部分患者替代终点的情况。
AI 中文摘要
我们开发了基于配对二元主要终点和短期替代终点的McNemar检验的盲法样本量重新估计策略，该研究由一项针对儿童青光眼的前瞻性随机临床试验驱动。我们推导了中期分析时给定主要终点的McNemar检验的条件功效表达式，并补充了样本量重新估计规则，结果表明该方法能保持I类错误率，同时允许选择第二阶段样本量以达到预先指定的目标功效。对于中期仅能获得部分患者短期替代终点的情况，我们引入了基于替代的重新估计方法，该方法利用替代终点到主要结局的转移率，对所有可能的主要终点不一致配对数量进行条件设定；我们还展示了如何从同时拥有替代终点和主要终点的子样本数据中估计这些转移率，推导了基于替代终点的条件功效和样本量规则，并以驱动该研究的试验为例说明了其应用。
英文摘要
We develop blinded sample size re-estimation strategies for McNemar's test based on paired binary primary and secondary short-term surrogate endpoints. The development is motivated by a prospective randomized clinical trial on childhood glaucoma. A conditional power expression for McNemar's test given the primary endpoint at an interim analysis is derived and complemented by a sample size re-estimation rule. We show that this procedure preserves the type I error rate while allowing the second-stage sample size to be chosen to attain a prespecified target power. In the case where for some patients only a short-term surrogate endpoint is available at interim, we introduce a surrogate-based re-estimation approach that conditions on all possible numbers of primary-endpoint discordant pairs using transition rates from the surrogate to the primary outcome. We show how these transition rates can be estimated from data on a subsample for which both surrogate and primary endpoint are available. We derive the resulting surrogate endpoint-based conditional power and sample size rule and illustrate their use with the example of the motivating trial.
