The appropriateness of 30-day mortality as a quality metric in colorectal cancer surgery.

BACKGROUND: Our study compares 30-day vs. 90-day mortality following colorectal cancer surgery (CRS), and examines hospital performance ranking based on this assessment.

METHODS: Mortality rates were compared between 30 vs. 90 days following CRS for patients with stage I-III colorectal cancers from the National Cancer Database (2004-2012). Risk-adjusted hierarchical regression models evaluated hospital performance based on mortality. Hospitals were ranked into top (10%), middle (80%), and lowest (10%) performance groups.

RESULTS: Among 185,464 patients, 90-day mortality was nearly double the 30-day mortality (4.4% vs. 2.5%). Following risk adjustment 176 hospitals changed performance ranking: 39% in the top 30-day mortality group changed ranking to the middle group; 37% of hospitals in the lowest 30-day group changed ranking to the middle 90-day group.

CONCLUSIONS: Evaluation of hospital performance based on 30-day mortality is associated with misclassification for 15% of hospitals. Ninety-day mortality may be a better quality metric in oncologic CRS.