Treatment effects of aspirin, warfarin, and nonvitamin K oral anticoagulants (NOACs) were compared using no thromboprophylaxis as a reference in a bivariate analysis. Incidence rate ratios (IRRs) of thromboembolic events (TEs) are reported on the y-axis and IRRs of major bleeding (MB) on x-axis. No thromboprophylaxis as a reference has a neutral effect on TE and MB, which equals 1 on the x- and y-axes. NOAC were associated with the greatest reduction in thromboembolic events, yet the greatest risk of major bleeding. Aspirin tended to have the most favorable overall profile, with both a significantly reduced risk of thromboembolic events and a tendency toward lower risk of MB.