Table A13:

Risk of Bias^a Among Randomized Controlled Trials (Cochrane Risk of Bias Tool)

Author, Year	Random Sequence Generation	Allocation Concealment	Blinding of Participants and Personnel	Blinding of Outcome Assessment	Incomplete Outcome Data	Selective Reporting	Other Bias
Mack et al, 201918 PARTNER	Low	Low	Lowb	Lowb	Low	Low	None
Popma et al, 201917 Evolut LRT	Low	Low	Lowc	Lowc	Low (30 d) Uncleard (1 y) Highd (2 y)	Low	None

^aPossible risk of bias levels: low, high, and unclear.

^bPatients and study personnel were not blinded to treatment assigned. However, we considered risk of bias to be low, as all components of the primary end point and key secondary end points were adjudicated by clinical events committee (members were aware of treatment assignment). Committee members included cardiologists and cardiothoracic surgeons who were not involved in the study and had no conflicts of interest. Primary outcome: composite of all-cause mortality, stroke, or rehospitalization at 1 year. Key secondary end points: stroke, composite of death or stroke, new-onset atrial fibrillation, poor treatment outcome (composite of death or a low Kansas City Cardiomyopathy Questionnaire, overall summary score at 30 days, and length of index hospitalization.

^cEchocardiographic studies were assessed at independent core laboratory. An independent academic clinical-events committee adjudicated all end points, using standard definitions. End-point adjudication was blinded when feasible.

^dCurrent publication provides results of prespecified interim analysis performed when 784 (53%) and 137 (9.3%) patients had reached 1 and 2 years of follow-up, respectively. Although appropriate imputation methods were used for missing data, given the high proportion of patients for which outcome data were unavailable at 1 year, it is difficult to ascertain whether missing outcomes would result in relevant bias in the effect estimate. At 2 years, given extent of the imputation (91%), we considered results to be at high risk of bias.