What are the rates of major bleeding on vitamin K antagonists (VKAs) among observational cohorts?
The rates of major bleeding on vitamin K antagonists (VKAs) among observational cohorts are shown in e-Table 8 and demonstrate highly variable rates, ranging from 1% to 3% per year. Nevertheless, there is significant heterogeneity between the study population characteristics, the inclusion of inception vs experienced OAC cohorts, significant disparity in the exposure period (follow-up) and differences in the definitions of major bleeding employed.