To compare performance across all institutions in terms of mortality, the observed vs expected mortality ratio (O:E) is utilized. The expected mortality is based on the patient's clinical acuity and severity of comorbidities. Therefore, institutions with a higher case mix index have a higher expected mortality. However, when the observed mortality is lower than the expected, the ratio becomes less than 1.
The goal for O:E ratio varies from one institution to another as well as within the same institution year to year.
The current graph demonstrates stability in O:E mortality since 2020. Maintaining performance around 0.5 indicates mortality is much lower than expected. Vizient data are used in this calculation to make effective comparisons.