Overall Survival As the Outcome for Randomized Clinical Trials With Effective Subsequent Therapies

摘要: We review how overall survival (OS) comparisons should be interpreted with increasing availability of effective therapies that can given subsequently to the treatment assigned in a randomized clinical trial (RCT). examine detail subsequent influence OS under varying conditions RCTs. A therapy after tumor progression (or relapse) an RCT works better standard arm than experimental will lead smaller difference (possibly no difference) one would see if was not available. Subsequent treatments are equally arms expected affect absolute benefit but make relative improvement smaller. In trials which control patients cross over their condition worsens, could observed without cross-overs. particular, use ...