Surgery Calculators
16 calculators & risk scores
Browse 16 Surgery clinical calculators and risk scores used in everyday UK practice. Every tool runs entirely in your browser — enter the values and get instant scoring, colour-coded interpretation bands and a link to the underlying guideline or publication. ClinCalc Pro is free, needs no sign-up, and is built for working clinicians.
These surgery tools span Upper GI Surgery, Prognosis, Diagnosis, Perioperative Risk, Postoperative, Appendicitis and more.
- Boey Score (Perforated Peptic Ulcer)Predicts mortality after emergency surgery for perforated peptic ulcer. Three simple risk factors.
- Surgical Apgar Score (SAS)Intraoperative 3-variable score predicting major postoperative complications and death within 30 days.
- Alvarado Score for AppendicitisClinical and laboratory scoring system for acute appendicitis. Helps determine need for CT and surgical consultation.
- P-POSSUM — Perioperative Mortality ScorePortsmouth POSSUM (P-POSSUM) predicts in-hospital mortality for general surgical patients from 12 physiological and 6 operative variables. Used for audit and consent.
- SORT — Surgical Outcome Risk ToolUK-derived tool predicting 30-day postoperative mortality for in-hospital non-cardiac surgery. Validated in 22,000 patients. Endorsed by RCS England.
- Clavien-Dindo Classification of Surgical ComplicationsInternationally standardised grading system for postoperative complications from Grade I (minor deviation) to Grade V (death). Mandatory for surgical audit and research.
- Paediatric Appendicitis Score (PAS)8-item score to predict appendicitis in children aged 3–18 years. Score ≥ 6 has sensitivity > 90% for appendicitis.
- P-POSSUM Score (Perioperative Mortality Risk)Portsmouth POSSUM (Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity) predicts in-hospital mortality after surgery from 12 physiological and 6 operative variables.
- Alvarado Score (Appendicitis)Estimates probability of acute appendicitis using clinical and laboratory findings. Guides CT scan and surgical referral decisions. Also known as MANTRELS score.
- Colorectal Cancer Staging (Dukes/TNM)Stages colorectal cancer using modified Dukes and TNM classification. Guides adjuvant chemotherapy and surveillance decisions.
- Breast Cancer Staging (TNM/AJCC 8th)Stages breast cancer by the AJCC 8th edition anatomic stage groups (TNM). Guides adjuvant therapy, sentinel node biopsy, and radiotherapy decisions.
- HERNIAscore — Incisional Hernia RiskPredicts ventral incisional hernia after abdominal surgery (HERNIAscore, Goodenough 2015). Guides prophylactic mesh placement decisions.
- Thyroid Cancer Risk Stratification (ATA)Stratifies differentiated thyroid cancer recurrence risk using ATA 2015 guidelines. Guides extent of surgery, radioiodine (RAI), and surveillance intensity. Not for poorly differentiated or anaplastic thyroid cancer.
- NELA Risk Score (Emergency Laparotomy)National Emergency Laparotomy Audit (NELA) risk model predicts 30-day mortality for emergency laparotomy. Mandated for all emergency laparotomies in England and Wales.
- CR-POSSUM — Colorectal POSSUMColorectal-specific POSSUM (Tekkis 2004) predicting operative mortality after colorectal surgery from a physiological score and an operative severity score.
- Comprehensive Complication Index (CCI)Single 0–100 score summarising all postoperative complications by severity (Slankamenac 2013). Enter the number of complications of each Clavien-Dindo grade.