About the Caprini VTE Risk Score
The Caprini risk assessment model is a points-based score that estimates the risk of venous thromboembolism (VTE) — deep vein thrombosis and pulmonary embolism — in surgical patients. Each risk factor carries 1, 2, 3 or 5 points according to how strongly it raises clot risk: age, type of surgery, recent illness, immobility, cancer, previous clots and inherited or acquired thrombophilias. This calculator uses the 2005 version of the model as reproduced in the American College of Chest Physicians (ACCP) 2012 guideline.
The total places the patient in one of four groups used by the ACCP for general and abdominal-pelvic surgery: very low (0 points), low (1–2), moderate (3–4) or high (5 or more). The calculator also shows the ACCP estimate of baseline symptomatic VTE risk in each group without prophylaxis: the guideline authors took the VTE rates observed in the retrospective validation cohort of Bahl and colleagues and adjusted them for the prophylaxis those patients received.
The score is intended for clinicians and surgical teams completing a pre-operative VTE assessment. It has also been studied in plastic and reconstructive surgery, but it is less established in other populations. It estimates risk only; decisions about prophylaxis must weigh bleeding risk and follow local protocols and specialist advice.
With the default inputs, the caprini score is 3. Change any value above to recalculate instantly.
How to use the caprini vte risk score
- 1Select the patient’s age band.
- 2Choose the type of surgery planned (or none for a medical patient).
- 3Switch on every other risk factor that applies, including family history and thrombophilias.
- 4Read the total score and ACCP risk category.
- 5Use the estimate alongside bleeding risk and local VTE protocols.
Formula and method
Every risk factor present adds its points; the total is not capped. One-point factors include age 41–60, minor surgery, BMI over 25, swollen legs, varicose veins, pregnancy or the postpartum period, hormonal therapy and recent serious medical illness. Two-point factors include age 61–74, major, laparoscopic or arthroscopic surgery, malignancy, bed confinement over 72 hours, a plaster cast and central venous access. Three-point factors are age 75 or more, a personal or family history of VTE and thrombophilias, and five-point factors are stroke or acute spinal cord injury within a month, elective lower-limb arthroplasty and hip, pelvis or leg fracture.
The ACCP 2012 guideline maps scores to baseline symptomatic VTE risks (without prophylaxis) of under 0.5%, about 1.5%, about 3.0% and about 6.0% for very low, low, moderate and high risk.
- Score
- Sum of points for all risk factors present
- VTE
- Venous thromboembolism (deep vein thrombosis or pulmonary embolism)
Worked examples
50-year-old having major open surgery
Age 41–60 scores 1 and major open surgery lasting over 45 minutes scores 2, for a total of 3 — moderate risk, with an estimated baseline VTE risk of about 3% without prophylaxis.
78-year-old for hip replacement
Age 75 or over scores 3, elective lower-extremity arthroplasty scores 5 and a BMI over 25 adds 1, giving 9 points — firmly in the high-risk group.
Young woman on the pill having minor surgery
Age 40 or under scores 0, minor surgery 1 and oral contraceptive use 1, for a total of 2 points — low risk, around 1.5% baseline VTE risk.
Cancer patient with a previous DVT
Age 61–74 (2) + major open surgery (2) + malignancy (2) + previous VTE (3) = 9 points, placing the patient in the high-risk group.
Frequently asked questions
What is a high Caprini score?+
In the ACCP 2012 guideline a Caprini score of 5 or more is high risk, with an estimated baseline symptomatic VTE risk of about 6% after general or abdominal-pelvic surgery without prophylaxis. Scores of 3–4 are moderate risk and 1–2 low risk.
Which version of the Caprini score does this use?+
This calculator uses the 2005 Caprini risk assessment model, which is the version reproduced in the ACCP 2012 antithrombotic guideline (Gould et al., Chest). Some later versions add or reweight items such as BMI over 40 or smoking.
Who was the Caprini score validated in?+
The validation used by the ACCP guideline was a large retrospective surgical cohort studied by Bahl and colleagues, which included general, vascular and urological surgery patients. It has also been validated in plastic and reconstructive surgery, where the same scores carry lower absolute risks. Evidence in medical, obstetric and orthopaedic trauma patients is more limited.
Does the Caprini score tell me which prophylaxis to use?+
No. The score only estimates baseline clot risk. Choosing mechanical or drug prophylaxis also depends on bleeding risk, the type of surgery, kidney function and local protocols, and must be decided by the treating team.
Why does family history count for 3 points?+
A first-degree relative with VTE suggests an inherited tendency to clot even when no specific thrombophilia has been identified, so the model weights it the same as a known thrombophilia or a personal history of VTE.
For healthcare professionals and education only. This calculator implements a published formula or score but is not a diagnosis and does not replace clinical judgment. Verify inputs and results against the original source before using them in patient care.