The Caprini tool is used to stratify a patient's individual risk of developing venous thromboembolism, particularly in the surgical and hospitalized patient setting, by assigning weighted points to multiple risk factors. The resulting total score categorizes patients into risk tiers that guide thromboprophylaxis decisions. It is one of several validated tools used for structured perioperative risk assessment.

The Caprini score incorporates factors such as patient age, body mass index, prior history of venous thromboembolism, active malignancy, planned surgery type and duration, and other relevant comorbidities. Each factor carries a different weighted point value based on its associated thrombotic risk. The cumulative score determines the overall risk category assigned to the patient.

Higher Caprini scores generally indicate a greater need for pharmacologic or mechanical thromboprophylaxis, with specific score thresholds often used to guide the intensity and duration of preventive measures. Lower-risk patients may require only early mobilization without pharmacologic prophylaxis. Healthcare professionals should apply the score alongside local institutional protocols and individual patient bleeding risk when finalizing a prevention plan.