Time-lag bias induced by unobserved heterogeneity: comparing treated patients to controls with a different start of follow-up
未观测异质性引起的时间滞后偏差:随访起点不同的治疗组与对照组比较
In comparative effectiveness research, treated and control patients might have a different start of follow-up as treatment is often started later in the disease trajectory. This typically occurs when data from treated and controls are not collected within the same source. Only patients who did not yet experience the event of interest whilst in the control condition end up in the treatment data source. In case of unobserved heterogeneity, these treated patients will have a…