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respiratory emergency

Wells' Criteria for Pulmonary Embolism

Pre-test probability score for pulmonary embolism. Guides decisions regarding D-dimer testing and CT pulmonary angiography (CTPA) in suspected PE.

Used in: Venous Thromboembolism (DVT & PE)

Score interpretation

Low Probability (~3.4% PE) 0–1.9

Low pre-test probability. PE prevalence ~3.4%.

→ Check D-dimer; if negative, PE excluded; if positive, proceed to CTPA

Moderate Probability (~27.8% PE) 2–6

Moderate pre-test probability. PE prevalence ~27.8%.

→ D-dimer (if ≤4) or direct CTPA (if score >4 — two-level Wells); CTPA if D-dimer positive

High Probability (~78.4% PE) 6.1–99

High pre-test probability. PE prevalence ~78.4%.

→ Proceed directly to CTPA; do not use D-dimer — sensitivity insufficient at this pre-test probability

Interpretation bands for the Wells PE Score. Apply clinical judgement and local guidance.

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.