Many trials are designed to collect outcomes at pre-specified times after randomization. However, in practice, there is often substantial variability in the times at which participants are actually assessed, which poses a challenge to learning about the treatment effects at the targeted assessment times. Any method for analyzing a trial with such irregular assessment times relies on untestable assumptions. Therefore, conducting a sensitivity analysis is an important step that can strengthen conclusions from such trials. However, no sensitivity analysis methodology has been developed. We develop a methodology that accounts for possibly informative assessment times, where assessment at time t may be related to the outcome at that time, even after accounting for observed past history. We implement our methodology using a new augmented inverse-intensity-weighted estimator, and we apply it to a trial of low-income participants with uncontrolled asthma. We also evaluate the performance of our estimation procedure in a realistic simulation study.

翻译：许多试验的目的是在随机评估之后的预定时间收集结果,但在实践中,实际评估参与者的时间往往有很大差异,这给在有目标的评估时间了解治疗效果带来挑战。任何分析这种不定期评估时间的试验的方法都依赖于无法测试的假设。因此,进行敏感性分析是能够加强这种试验结论的重要一步。然而,没有制定敏感性分析方法。我们制定了一种方法,考虑到可能的信息丰富的评估时间,即使考虑到以往的观察历史,时间的评估也可能与当时的评估结果相关。我们采用新的强化反强度加权估测器执行我们的方法,并将它应用于对患有失控哮喘的低收入参与者的试验。我们还在现实的模拟研究中评估我们估算程序的执行情况。