Key points (98/100 words)
  1. Clone-censor-weighting (CCW) can compare the effects of different treatment initiation windows.
  2. The causal contrast estimated by CCW when studying initiation windows varies depending on when the population naturally initiates, making information on initiation timings essential context for estimates.
  3. We provide straightforward analytic code for a CCW analysis within a cohort constructed from publicly available synthetic Medicare claims data.
  4. We demonstrate how to construct inverse probability of censoring weights that only allow recent initiators to “stand in” for those censored at the end of windows to avoid selection bias when exposure effects vary over time.