Colorectal Surgery
Readmission Risk
Calculator (CRS-RRC)

This risk calculator is only intended for use in patients who underwent elective colon or rectal resection.
Pre-operative Risk Factors
Peri-operative Risk Factors
Post-operative Risk Factors

30-Day Unplanned Readmission Risk
Readmission Risk Category

Readmissions reflect adverse patient outcomes and clinicians currently lack accurate models to predict readmission risk.


We sought to create a readmission risk calculator for use in the post-operative setting following elective colon and rectal surgery.


Patients who underwent elective abdominal colon or rectal resection were identified from 2012-2014 American College of Surgery-National Surgical Quality Improvement Program (ACS-NSQIP) data. A model was created with 60% of the NSQIP sample using multivariable logistic regression to stratify patients into low/medium and high-risk categories. The model was validated with the remaining 40% of the NSQIP sample and 2016-2018 institutional data.


The study included both national and institutional data.

Main Outcome Measures

The primary outcome was readmission within 30 days of surgery. Secondary outcomes included reasons for and time interval to readmission.


The model discrimination (c-statistic) was 0.76 (95% CI 0.75-0.76, p<0.0001) in the NSQIP model creation cohort (n=50,508), 0.70 (95% CI 0.69-0.70, p<0.0001) in the NSQIP validation cohort (n=33,714), and 0.62 (95% CI 0.54-0.70, p=0.04) in the institutional cohort (n=400). High risk was designated as ≥8.7% readmission risk. Readmission rates in NSQIP and institutional data were 10.7% and 8.8% overall; of patients in the high-risk category, observed readmission rate was 22.1% in NSQIP and 12.4% in the institutional cohorts. Overall median interval from surgery to readmission was 14 days in NSQIP and 11 days institutionally. The most common reasons for readmission were organ space infection, bowel obstruction/paralytic ileus, and dehydration in both NSQIP and institutional data.


This was a retrospective observational review.


For patients who undergo elective colon and rectal surgery, use of a readmission risk calculator developed for post-operative use can identify high risk patients for potential amelioration of modifiable risk factors, more intensive outpatient follow-up, or planned readmission.

The sole purpose of this web site is to provide educational information about the health conditions studied in our research registries. We assume no responsibility for how you use or interpret this Risk Prediction Model For Readmission After Colorectal Surgery or any other information provided on this web site.