All Lines Is the Right Approach: Selecting Patient Lines of Therapy for an External Comparator Arm

Using all eligible lines of therapy for each patient when constructing ECAs minimizes bias and preserves the SAT target population. Alternative methods can lead to biased estimates or, in the case of the first eligible line method, require changes to the clinical question that may shrink the SAT population. We recommend adopting the all eligible lines method with variance correction and adjustment for line of therapy to ensure valid comparative effectiveness analyses.