Anchored covariate-adjusted indirect comparisons inform reimbursement decisions where there are no head-to-head trials between the treatments of interest, there is a common comparator arm shared by the studies, and there are patient-level data limitations. Matching-adjusted indirect comparison (MAIC) is the most widely used covariate-adjusted indirect comparison method. MAIC has poor precision and is inefficient when the effective sample size after weighting is small. A modular extension to MAIC, termed two-stage matching-adjusted indirect comparison (2SMAIC), is proposed. This uses two parametric models. One estimates the treatment assignment mechanism in the study with individual patient data (IPD), the other estimates the trial assignment mechanism. The resulting weights seek to balance covariates between treatment arms and across studies. A simulation study provides proof-of-principle in an indirect comparison performed across two randomized trials and explores the use of weight truncation in combination with MAIC for the first time. Despite enforcing randomization and knowing the true treatment assignment mechanism in the IPD trial, 2SMAIC yields improved precision and efficiency with respect to MAIC in all scenarios, while maintaining similarly low levels of bias. The two-stage approach is effective when sample sizes in the IPD trial are low, as it controls for chance imbalances in prognostic baseline covariates between study arms. It is not as effective when overlap between the trials' target populations is poor and the extremity of the weights is high. In these scenarios, truncation leads to substantial precision and efficiency gains but induces considerable bias. The combination of a two-stage approach with truncation produces the highest precision and efficiency improvements.
翻译:在对利息的处理方法之间没有头对头试验的情况下,对偿还决定进行共变调整间接比较,为作出偿还决定提供了依据;在研究中,有一个共同的参照网,有一个共同的参照网;有病人一级的数据限制;匹配调整间接比较(MAIC)是最广泛使用的共变调调整间接比较方法;MAIC在加权后的有效抽样规模小时,其精确度不高,效率也低;提议对MAIC进行模块扩展,称为两阶段匹配调整间接比较(2SMAIC),这使用两个参数模型;一个用个人病人数据(IPD)对研究中的治疗分配机制进行估计,导致对试验分配机制进行其他估计;由此产生的加权力求平衡处理武器和跨研究之间的差异;模拟研究在两次随机试验中进行间接比较,提供原则证明,并探索在第一次与MAIC进行有效抽样比较时使用重量调整;尽管在IPD试验中采用随机调整,但了解真正的治疗方法,但在各种假设中,对MAIC的精确度和效率都有提高;在两次试验中,在实际的精确度上,在两种试算中,其效率为相当低的数值的数值的数值上,在两种试算中,它们之间具有相当的精确的精确性。