Response to Letters Regarding Article, “Bayesian Methods Affirm the Use of Percutaneous Coronary Intervention to Improve Survival in Patients With Unprotected Left Main Coronary Artery Disease”

Abstract

Dr Diamond explores the important issue of relating statistical inference to clinical significance in our recent report.1 He raises a specific concern about the width of the 95% Bayesian credible interval of the odds ratio, ranging from 0.68 to 1.45, and questions whether the approach that we used actually affirms that percutaneous coronary intervention (PCI) should be considered as an alternative to coronary artery bypass (CABG) surgery for selected patients with unprotected left main coronary artery disease, as suggested by the Class IIa recommendation from the American Heart Association Foundation/American Heart Association.2 The Bayesian credible intervals in our analysis were similar to the classical confidence intervals and included the value 1.0, suggesting that the 1-year mortality after PCI or CABG was similar. The seemingly wide Bayesian credible intervals were the consequences of sample size. To illustrate this, we note from the data that the 1-year mortality rate after CABG was 6.56%1 and estimate that a sample size of 90 000 per treatment arm would be …