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PulmonologyPulmonaryClinical Decision RuleOpen Access / Terms Apply

CURB-65

CURB-65 Severity Score for Community-Acquired Pneumonia

Guides outpatient vs inpatient vs intensive care unit (ICU) admission for adult patients presenting with pneumonia.

5 items·Estimated time: ~2 min·Evidence references below
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CURB-65 Parameters

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About the CURB-65

Validated clinical prediction rule determining 30-day mortality and triage for community-acquired pneumonia.

Scoring Methodology & Interpretation

The CURB-65 uses a validated sum algorithm with predefined clinical cutoffs established in peer-reviewed derivation and validation cohorts:

Score RangeSeverity ClassificationClinical Interpretation
0 – 1Low Mortality Risk30-day mortality risk is low (~0.7% – 2.1%).
2 – 2Intermediate Mortality Risk30-day mortality risk is ~9.2%.
3 – 5High Mortality Risk30-day mortality risk is 15% to 40%. Severe community-acquired pneumonia.

Clinical Pearls & Considerations

  • The "CRB-65" variant omits the urea measurement for community/primary care triage when laboratory blood tests are unavailable.
Copyright & Intellectual Property Attribution:

British Thoracic Society (BTS) Lim et al. (2003). Clinical guideline prediction tool.

License: Open Access / Clinical Guideline Tool
Clinical Disclaimer & Scope of Use

This instrument is designed for educational, informational, and clinical reference purposes. Screening scores do not constitute a definitive medical diagnosis. Individual clinical management must integrate full diagnostic history, physical examination, and laboratory data by a licensed healthcare professional.

  • Does not evaluate pulse oximetry or arterial blood gas oxygenation.
  • Underlying immunosuppression, cirrhosis, or neuromuscular disease require clinician judgment beyond the score.
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Evidence & Primary Literature Citations

  1. Key Validation Study
    Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study.
    Lim WS, van der Eerden MM, Laing R, et al. Thorax. 2003;58:377-382.
    PMID: 12728155DOI

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