A New Causal Approach to Account for Treatment Switching in Randomized Experiments under a Structural Cumulative Survival Model

  title={A New Causal Approach to Account for Treatment Switching in Randomized Experiments under a Structural Cumulative Survival Model},
  author={Andrew Ying and Eric J Tchetgen Tchetgen},
Background: Treatment switching in a randomized controlled trial is said to occur when a patient randomized to one treatment arm switches to another treatment arm during follow-up. This can occur at the point of disease progression, whereby patients in the control arm may be offered the experimental treatment. It is widely known that failure to account for treatment switching can seriously dilute the estimated effect of treatment on overall survival. In this paper, we aim to account for the… Expand
Instrumental variable estimation for a time-varying treatment and a time-to-event outcome via structural nested cumulative failure time models
  • Joy Shi, Sonja A. Swanson, P. Kraft, Bernard Rosner, I. Vivo, Miguel A. Hernán
  • BMC Medical Research Methodology
  • 2021
Background In many applications of instrumental variable (IV) methods, the treatments of interest are intrinsically time-varying and outcomes of interest are failure time outcomes. A common exampleExpand


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