Padua Prediction Score Calculator
The Padua Prediction Score is a validated 11-item clinical tool that stratifies hospitalized medical patients into low or high risk for venous thromboembolism (VTE). Select each risk factor that applies to your patient. The score and thromboprophylaxis recommendation update instantly. A score of 4 or higher identifies high-risk patients who benefit from pharmacological prophylaxis.
Formula
Worked example
A 72-year-old patient with active lung cancer (3 pts) who is bed-bound for 4 days (3 pts): score = 6, which is >=4, placing the patient in the high-risk category. Pharmacological thromboprophylaxis is recommended unless contraindicated.
What is the Padua Prediction Score?
The Padua Prediction Score is a risk stratification tool developed at the University of Padua and validated in a prospective cohort of 1,180 hospitalized medical patients. Published in 2010 by Barbar and colleagues in the Journal of Thrombosis and Haemostasis, it assigns weighted points to 11 clinical risk factors for venous thromboembolism (VTE). The score helps clinicians decide which patients should receive pharmacological thromboprophylaxis during their hospital stay. A threshold of 4 points separates low-risk patients (in whom routine anticoagulation is not recommended) from high-risk patients (in whom prophylaxis reduces in-hospital VTE from about 11% to 2.2%).
The 11 scoring criteria explained
The four highest-weight factors each contribute 3 points: active cancer (including metastatic disease or recent chemo/radiotherapy), a prior episode of VTE (excluding superficial vein thrombosis), reduced mobility defined as bed rest with bathroom privileges only for at least 3 days, and a known thrombophilic condition such as antithrombin deficiency, protein C or S deficiency, factor V Leiden, prothrombin G20210A mutation, or antiphospholipid syndrome. Recent trauma or surgery within the preceding month adds 2 points. Six lower-weight factors each contribute 1 point: age 70 or older, heart and/or respiratory failure, acute myocardial infarction or ischemic stroke, acute infection or rheumatologic disorder, obesity (BMI 30 or higher), and ongoing hormonal treatment such as oral contraceptives or hormone replacement therapy. The maximum possible score is 20, though most patients score below 10.
How to use the Padua Score in practice
Assess the Padua Score at or near the time of hospital admission for medical (non-surgical) patients. Work through each of the 11 items and tick every one that applies to your patient. The score updates in real time. If the total is 4 or more, the patient is at high risk and pharmacological prophylaxis - most commonly low molecular weight heparin, unfractionated heparin, or fondaparinux - should be started unless there is a clear contraindication such as active bleeding, severe thrombocytopenia, or renal impairment (creatinine clearance below 30 mL/min). If the score is below 4, routine anticoagulation is not recommended, but mechanical methods such as graduated compression stockings or intermittent pneumatic compression may still be appropriate based on clinical context. The score should be reassessed whenever the patient's clinical status changes during the admission.
Evidence and limitations
In the original Barbar 2010 derivation and validation cohort, high-risk patients (score 4 or more) who received adequate thromboprophylaxis had a 2.2% rate of symptomatic VTE during the 90-day follow-up, compared with 11.0% in those who did not receive prophylaxis. Low-risk patients had a 0.3% rate regardless of prophylaxis status. The score has since been externally validated in multiple independent cohorts and is endorsed by major clinical guidelines including those from the American College of Chest Physicians (ACCP). Limitations include the fact that the original cohort was a single-center European study, the tool was derived for medical (non-surgical) inpatients and is not validated for post-operative patients, and it does not incorporate bleeding risk - a separate assessment of hemorrhagic risk is always required before initiating anticoagulation.
Padua Prediction Score - Criteria and Point Values
| Risk Factor | Points | Risk Level |
|---|---|---|
| Active cancer (metastases, or chemo/radio in last 6 months) | 3 | High |
| Previous VTE (excl. superficial thrombosis) | 3 | High |
| Reduced mobility (bed rest >=3 days) | 3 | High |
| Known thrombophilic condition | 3 | High |
| Recent trauma or surgery (within 1 month) | 2 | Moderate |
| Age >=70 years | 1 | Low |
| Heart and/or respiratory failure | 1 | Low |
| Acute MI or ischemic stroke | 1 | Low |
| Acute infection or rheumatologic disorder | 1 | Low |
| Obesity (BMI >=30) | 1 | Low |
| Ongoing hormonal treatment | 1 | Low |
All 11 criteria from the original Barbar 2010 validation study. Scores of 4 or more indicate high risk.
Frequently asked questions
What is a high Padua score?
A Padua score of 4 or higher is classified as high risk for VTE. In the original validation study, patients in this category had an 11% rate of venous thromboembolism when they did not receive prophylaxis. Pharmacological thromboprophylaxis is recommended for high-risk patients who do not have contraindications to anticoagulation.
Is the Padua Score used for surgical patients?
No. The Padua Prediction Score was specifically developed and validated for hospitalized medical (non-surgical) patients. For surgical patients, different VTE risk models are used, such as the Caprini RAM, which accounts for procedure type, operative duration, and surgical-specific risk factors. Applying the Padua Score to a surgical population would be outside its validated scope.
What prophylaxis is recommended for high-risk patients?
The Padua Score identifies patients who need prophylaxis, but does not specify the agent. Common options include low molecular weight heparin (LMWH) such as enoxaparin, unfractionated heparin (UFH), or fondaparinux. The choice depends on renal function, bleeding risk, body weight, and local protocol. A creatinine clearance below 30 mL/min may rule out standard LMWH dosing.
Can a patient with a low Padua Score still get VTE?
Yes, but the risk is much lower. In the original study, low-risk patients (score less than 4) had a VTE rate of approximately 0.3% at 90-day follow-up. No screening tool has perfect sensitivity, so clinical judgment remains essential. If a patient develops new symptoms suggestive of DVT or pulmonary embolism, diagnostic imaging is warranted regardless of the score.
Does the Padua Score include bleeding risk?
No. The Padua Score only assesses thrombotic risk. Before starting anticoagulation in a high-risk patient, a separate bleeding risk assessment is required. Contraindications to pharmacological prophylaxis include active bleeding, platelet count below 50,000/uL, severe hepatic failure, and creatinine clearance below 30 mL/min in patients on LMWH.
How often should the Padua Score be recalculated?
The score should be reassessed whenever the patient's clinical condition changes significantly - for example, if they develop a new infection, become bed-bound, start or stop hormonal therapy, or undergo surgery during the admission. Many institutions build Padua Score reassessment into daily clinical rounds for inpatient medical units.
Sources
- Barbar S, Noventa F, Rossetto V, et al. A risk assessment model for the identification of hospitalized medical patients at risk for venous thromboembolism: the Padua Prediction Score. J Thromb Haemost. 2010;8(11):2450-2457.
- Kahn SR, Lim W, Dunn AS, et al. Prevention of VTE in nonsurgical patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed. ACCP Guidelines. Chest. 2012;141(2 Suppl):e195S-e226S.