Outlier identification in colorectal surgery should separate elective and nonelective service components

Area of Science:

• Health Services Research
• Surgical Outcomes Analysis
• Public Health Reporting

Background:

• Identifying healthcare institutions with unusual outcomes is vital for quality improvement and reporting.
• Elective surgical outcomes have historically received more attention than nonelective outcomes.
• Differences in outlier identification between elective and nonelective patient groups remain underexplored.

Purpose of the Study:

• To compare the identification of institutional outliers for mortality following elective and nonelective colorectal resection in England.

Main Methods:

• A cohort study utilizing routine administrative data from English National Health Service Trusts.
• Ninety-day mortality was determined using statutory death records.
• Adjusted Trust-level mortality rates were calculated via multiple logistic regression, with outliers identified using funnel plots.

Main Results:

• The study included 195,118 patients across 147 Trusts, with 90-day mortality rates of 4% for elective and 18% for nonelective colorectal surgery.
• No institution identified as a high mortality outlier for elective surgery was also an outlier for nonelective surgery, and vice versa.
• Observed-to-expected mortality rates for elective and nonelective surgery showed moderate correlation (Spearman ρ = 0.50, p< 0.001).

Conclusions:

• Institutional mortality outlier status for elective and nonelective colorectal surgery is not strongly related.
• Separate reporting of mortality rates for elective and nonelective colorectal surgery patients is recommended.
• Separate reporting will provide a comprehensive view of colorectal services and guide quality improvement efforts.