Pulmonary embolism
PERC Rule
Apply only when clinical gestalt pre-test probability is < 15%. If all 8 criteria are absent, PE can be ruled out without D-dimer.
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Criteria
Tap every item that applies
Total score
0
PERC negative
Missed PE risk < 2% (below testing threshold)
Decision guide
PE ruled out — no D-dimer or imaging required (only if gestalt probability < 15%).
Ranges: 0 PERC negative1–8 PERC positive
References
- Kline JA, et al. Clinical criteria to prevent unnecessary diagnostic testing in ED patients with suspected PE. J Thromb Haemost 2004;2:1247-1255.
- Freund Y, et al. Effect of the PERC rule on subsequent thromboembolic events (PROPER). JAMA 2018;319:559-566.
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