An Assessment of Hospital Performance in Emergency General Surgery Using Direct and Indirect Standardization

The goal of this study was to assess 2 analytic strategies for comparing hospital outcomes among those with emergency general surgery (EGS) conditions, comparing a conventional risk stratification method with a less utilized, but equally informative strategy.

EGS is a complex set of heterogeneous, time-sensitive conditions that require expeditious treatment. Patients need a mechanism to evaluate how hospitals perform for similar populations treated within the hospital and a reliable metric that benchmarks outcomes across institutions.

We performed a retrospective cohort study assessing hospital outcomes for EGS Medicare beneficiaries from July 1, 2015, to June 30, 2018. Using direct standardization with balancing weights and indirect standardization with logistic regression, we compare hospital performance on a risk-adjusted composite adverse event rate. Performance based on each standardization modality was correlated using the Spearman rank coefficient.

There were 536,284 patients with a median (interquartile interval) age of 74.2 (72.9, 75.6) years treated at 1866 study hospitals. Direct and indirect standardization showed agreement on 92 low- and 76 high-performing hospitals. Adverse event rates for hospital rankings were strongly correlated between the 2 methods of standardization (0.83, P < 0.001). Rankings based on operative (0.75) and nonoperative (0.77) groups were also highly correlated (all P < 0.001).

Significant variation exists in EGS outcomes. Hospital performance is inconsistent between operative and nonoperative treatment. A small number of hospitals can be distinguished based on risk-adjusted outcomes regardless of analytic technique, suggesting opportunities for optimized care standardization and quality improvement.