Liu G Frank, Zhu G Ray, Cui Lu
Clinical Biostatistics, Merck Research Laboratories, North Wales, PA 19454, USA.
Stat Med. 2008 Feb 20;27(4):584-96. doi: 10.1002/sim.2998.
In clinical trials, the study sample size is often chosen to provide specific power at a single point of a treatment difference. When this treatment difference is not close to the true one, the actual power of the trial can deviate from the specified power. To address this issue, we consider obtaining a flexible sample size design that provides sufficient power and has close to the 'ideal' sample size over possible values of the true treatment difference within an interval. A performance score is proposed to assess the overall performance of these flexible sample size designs. Its application to the determination of the best solution among considered candidate sample size designs is discussed and illustrated through computer simulations.
在临床试验中，研究样本量通常是为了在治疗差异的单个点上提供特定的检验效能而选择的。当这种治疗差异与真实差异不接近时，试验的实际检验效能可能会偏离指定的检验效能。为了解决这个问题，我们考虑获得一种灵活的样本量设计，该设计在区间内真实治疗差异的可能值上提供足够的检验效能，并且接近“理想”样本量。提出了一个性能分数来评估这些灵活样本量设计的整体性能。通过计算机模拟讨论并说明了其在确定所考虑的候选样本量设计中的最佳解决方案方面的应用。
