Caprini Score Calculator
Add weighted Caprini risk factors to estimate venous thromboembolism risk and see the matching prophylaxis band.
What it does
The Caprini score is a weighted checklist for venous thromboembolism risk in adults. It is used most often before surgery and during medical admission. Each risk factor has a point value, and the total places the patient in a risk band that can be matched to a prophylaxis plan.
The model began with a smaller list of surgical risk factors and has been revised several times. The version used here includes age groups, major and minor surgery, malignancy, central venous access, prior venous thromboembolism, thrombophilia, and acute events such as stroke or spinal cord injury. The weights are cumulative, so a patient with several modest factors can score higher than a patient with one large factor.
The bands are 0 for very low risk, 1 to 2 for low risk, 3 to 4 for moderate risk, and 5 or more for high risk. Higher scores are linked to more postoperative venous thromboembolism in large cohorts. The score is not a treatment order. It should be read alongside bleeding risk, kidney function, platelet count, and the planned procedure.
Caprini is common in surgery because it captures procedure duration and immobility. It is also used in medical patients, though other models such as Padua were built specifically for medical admissions. A hospital may use one model across all adults or choose by service. The important step is to use the same model consistently so that changes in score mean something.
The original publications and later reviews differ in minor ways. Some forms split age into finer bands, and some add genetic markers. The input list on this page follows the widely used 2005 version. If your local form has different weights, follow the local form. The arithmetic here is a guide, not a substitute for the approved order set.
How to use
- Start with the age group. Age adds 0, 1, 2, or 3 points depending on the band.
- Work through the one point factors: minor surgery, BMI above 25, swollen legs, varicose veins, pregnancy, pregnancy complications, hormone therapy, sepsis, lung disease, abnormal pulmonary function, myocardial infarction, heart failure, inflammatory bowel disease, and bed rest.
- Add the two point factors: arthroscopic surgery, major surgery longer than 45 minutes, malignancy, bed rest longer than 72 hours, immobilizing cast, and central venous access.
- Add the three point factors: prior DVT or PE, family history of thrombosis, and known thrombophilia.
- Add the five point factors: stroke within one month, elective major lower limb arthroplasty, hip or pelvis or leg fracture, spinal cord injury, and multiple trauma.
- Total the points, match the total to the band, and compare the result with the local prophylaxis protocol and the patient's bleeding risk.
Formula
- Age
- 0 for age 40 or younger, 1 for 41 to 60, 2 for 61 to 74, 3 for 75 or older.
- 1 point factors
- Minor surgery, BMI above 25, swollen legs, varicose veins, pregnancy, pregnancy complications, hormone therapy, sepsis, lung disease, abnormal pulmonary function, myocardial infarction, heart failure, inflammatory bowel disease, bed rest.
- 2 point factors
- Arthroscopic surgery, major surgery longer than 45 minutes, malignancy, bed rest longer than 72 hours, immobilizing cast, central venous access.
- 3 point factors
- Prior DVT or PE, family history of thrombosis, known thrombophilia.
- 5 point factors
- Stroke within 1 month, elective major lower limb arthroplasty, hip or pelvis or leg fracture, spinal cord injury, multiple trauma.
The score is the sum of every factor that applies. Do not count the same condition twice under two labels. For example, active cancer and malignancy are one factor, not two. The bands above are the common Caprini cutoffs. Some services use a score of 5 or more to trigger extended prophylaxis after major cancer surgery, but duration depends on the procedure and bleeding risk. The score does not include platelet count, kidney function, or fall risk.
Worked example
Example: 8 points, high risk
A 68 year old patient has major surgery planned for malignancy and a central line is placed before surgery. No other factors apply.
- Age 61 to 74: 2 points.
- Major surgery longer than 45 minutes: 2 points.
- Malignancy: 2 points.
- Central venous access: 2 points.
- Add the remaining factors: all are 0 in this example.
- Total: 2 + 2 + 2 + 2 = 8.
- A total of 8 is 5 or more, so the risk band is high.
Reference table
| Points | Factors | Risk band |
|---|---|---|
| 1 | Age 41 to 60, minor surgery, BMI above 25, swollen legs, varicose veins, pregnancy, pregnancy complications, hormone therapy, sepsis, lung disease, abnormal pulmonary function, myocardial infarction, heart failure, inflammatory bowel disease, bed rest | Low when total is 1 to 2 |
| 2 | Age 61 to 74, arthroscopic surgery, major surgery longer than 45 minutes, malignancy, bed rest longer than 72 hours, cast, central venous access | Moderate when total is 3 to 4 |
| 3 | Age 75 or older, prior DVT or PE, family history of thrombosis, thrombophilia | High when total is 5 or more |
| 5 | Stroke within 1 month, elective major lower limb arthroplasty, hip or pelvis or leg fracture, spinal cord injury, multiple trauma | High when total is 5 or more |
| 0 | No factors and age 40 or younger | Very low |
| 8 | Worked example: age 2 plus surgery 2 plus malignancy 2 plus central line 2 | High |
Limits
- The score was built and validated mainly in surgical patients. It is less precise in medical admissions than models designed for that setting.
- It does not measure bleeding risk, so a high score cannot by itself justify anticoagulation.
- Some items depend on judgment, such as whether a lung disease is serious or whether bed rest is ongoing.
- Weights and age bands differ between published versions. Use the form approved by your hospital.
Common mistakes
- Counting malignancy and active cancer as two separate factors.
- Using BMI above 30 as the cutoff. The Caprini factor is BMI above 25.
- Forgetting central venous access, which adds 2 points and is easy to overlook.
- Scoring a remote history of DVT as a one point factor instead of the three point prior VTE factor.
- Treating a high score as an automatic order for anticoagulation without checking bleeding risk.
Try it yourself
Quick checks. Answers sit tucked under each question.
Age 41 to 60, minor surgery, BMI above 25, no other factors. What is the score and band?
1 + 1 + 1 = 3. The score is 3, which is moderate risk.
Age 75 or older, prior DVT, no other factors. What is the score and band?
3 + 3 = 6. The score is 6, which is high risk.
Age 40 or younger, no factors. What is the score and band?
0 + 0 = 0. The score is 0, which is very low risk.
Questions
What is a high Caprini score?
A total of 5 or more is high risk in the usual bands. Some surgical services use higher thresholds for extended prophylaxis.
Does Caprini apply to medical patients?
It is used in medical patients, but Padua was designed for that group. Follow the model adopted by your hospital.
Why is age weighted in bands?
Age is a strong risk factor for venous thromboembolism. The bands keep the form short while still giving older patients more points.
Is BMI above 25 the same as obesity?
No. BMI above 25 is the Caprini cutoff. Obesity is usually defined as BMI 30 or higher, which is a different threshold.
Can a score of 8 mean the patient must receive heparin?
Not automatically. The score supports prophylaxis, but bleeding risk, kidney function, platelet count, and procedure timing decide the drug and dose.
How often should the score be repeated?
Reassess when the clinical picture changes, such as after a new cancer diagnosis, a central line, prolonged bed rest, or a major operation.
Sources
- AHRQ: venous thromboembolism risk assessment models, including Caprini
- Review: evolution of the Caprini risk assessment score