Use of Administrative Claims to Assess Outcomes and Treatment Effect in Randomized Clinical Trials for Transcatheter Aortic Valve Replacement: Findings From the EXTEND Study

BACKGROUNDWhether passively collected data can substitute for adjudicated outcomes to reproduce the magnitude and direction of treatment effect observed in cardiovascular clinical trials is not well known. METHODSWe linked adults ≥65 years of age in the HiR (US CoreValve Pivotal High Risk) and SURTAVI trials (Surgical or Transcatheter Aortic Valve Replacement in Intermediate-Risk Patients) to 100% Medicare inpatient claims, January 1, 2011, to December 31, 2016. Primary (eg, death and stroke) and secondary trial end points were compared across treatment arms (eg, transcatheter aortic valve replacement [TAVR] versus surgical aortic valve replacement [SAVR]) using trial-adjudicated outcomes versus outcomes derived from claims at 1 year (HiR) or 2 years (SURTAVI). RESULTSAmong 600 linked HiR participants (linkage rate, 80.0%), the rate of the trial's primary end point of all-cause mortality occurred in 13.7% of patients receiving TAVR and 16.4% of patients receiving SAVR at 1 year by using both trial data (hazard ratio, 0.84 [95% CI, 0.65-1.09]; P=0.33) and claims data (hazard ratio, 0.86 [95% CI, 0.66-1.11]; P=0.34; interaction P value=0.80). Noninferiority of TAVR relative to SAVR was seen by using both trial- and claims-based outcomes (Pnoninferiority