Pulmonary Embolism Clinical Prediction Rules

Author: Michelle Lin, MD
Updated: 6/3/2011

Pulmonary Embolism (PE): Clinical Prediction Rules

Note: These rules should be used with caution, because none of these scoring protocols are perfect. For instance, in a very recent publication of the Journal of Thrombosis and Haemostasis, the authors found that the PERC rule may not actually safely exclude PEs.

Pulmonary Embolism Rule-out Criteria (PERC) Rule

Kline et al. J Thromb Haem 2004; Kline et al. J Thromb Haem 2008

  • Age <50 years
  • Heart rate <100 bpm
  • Room air oxygen saturation ≥95%
  • No prior DVT or PE
  • No recent trauma or surgery (4 weeks)
  • No hemoptysis
  • No exogenous estrogen
  • No clinical signs suggestive of DVT

If all 8 present: Only 1% risk for venous thromboembolism (VTE) at 45 days.

Wells' Score

Wells et al. Thromb Haemost; Wells et al. Ann Intern Med

Clinical Finding or Risk Factor Points
Clinical signs and symptoms of DVT +3
PE is #1 diagnosis, or equally likely +3
Heart rate > 100 bpm +1.5
Immobilization for ≥ 3 days, or Surgery in ≤ 4 wks +1.5
Previous, objectively diagnosed PE or DVT +1.5
Hemoptysis +1
Malignancy with treatment within 6 months, or palliative +1
Total # Wells points Risk for PE at 3 months
<2 1.3%
2-6 16.2%
>6 40.6%
≤4 and neg D-Dimer 0.5% non-fatal VTE [Van Belle, 2006]

Simplified Geneva Score

Klok FA et al. Arch Intern Med 2008

Clinical Finding or Risk Factor Points
Age > 65 years +1
Previous DVT or PE +1
Surgery (general anesthesia) or fracture (lower limbs) ≤ 1 month +1
Active malignancy (solid or hematologic, 1 currently active or considered cured < 1 year) +1
Unilateral lower-limb pain +1
Hemoptysis +1
Heart rate ≥ 75 bpm +1
Unilateral edema +1
Pain on lower-limb deep venous palpation +4
Total # of points Incidence of PE
0-1 7.7%
2-4 29.4%
5-7 64.3%


  • Klok FA et al.Simplification of the revised Geneva score for assessing clinical probability of pulmonary embolism. Arch Intern Med 2008 [PubMed]
  • Wells et al. Excluding pulmonary embolism at the bedside without diagnostic imaging: management of patients with suspected pulmonary embolism presenting to the emergency department by using a simple clinical model and d-dimer. Ann Intern Med 2001. [PubMed]
  • Van Belle et al. Effectiveness of managing suspected pulmonary embolism using an algorithm combining clinical probability, D-dimer testing, and computed tomography.JAMA 2006 [PubMed]
  • Hugli O, Righini M, Le Gal G, Roy PM, Sanchez O, Verschuren F, Meyer G, Bounameaux H, Aujesky D.The pulmonary embolism rule-out criteria (PERC) rule does not safely exclude pulmonary embolism.J Thromb Haemost. 2011 Feb;9(2):300-4. [PubMed]
  • Kline et al. Clinical criteria to prevent unnecessary diagnostic testing in emergency department patients with suspected pulmonary embolism.J Thromb Haem 2004. [PubMed]
  • Kline et al. Prospective multicenter evaluation of the pulmonary embolism rule-out criteria. J Thromb Haem 2008. [PubMed]
  • Wells et al.Derivation of a simple clinical model to categorize patients probability of pulmonary embolism: increasing the models utility with the SimpliRED D-dimer. Thromb Haemost 2000 [PubMed]