Figure 1.
Sensitivity analysis of the potential impact of an unobserved confounder, U, on the association of quality indicators and mortality. P0: Prevalence of U among those not receiving the quality measure. P1: Prevalence of U among those receiving the quality measure. Shaded areas represent combinations of P1, P0, and OR(U) that would result in a loss of significance of the quality indicator–mortality association. From darkest to lightest gray: OR(U) = 2.14, 1.59, 1.41, 1.14. Areas with no shading remained significant for selected OR(U) values.
