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CRB-65 Score for Pneumonia (no labs)

CRB-65 is CURB-65 without urea, for use where blood tests are unavailable: Confusion, Respiratory rate ≥30, SBP <90 or DBP ≤60, and age ≥65 (0–4 points). 0 is low risk (home treatment usually appropriate), 1–2 intermediate (consider hospital referral), 3–4 high risk (urgent admission).

  • Age (years)
  • New confusion (yes/no, +1)
  • Respiratory rate (/min)
  • Systolic blood pressure (mmHg or kPa)
  • Diastolic blood pressure (mmHg or kPa)
—

Interpretation

ResultMeaning
0Low risk: home treatment
1–2Intermediate: consider hospital referral
3–4High risk: urgent admission

Formula

One point each: Confusion · RR ≥30/min · SBP <90 or DBP ≤60 mmHg · Age ≥65

Clinical pearls

  • Designed for primary care where urea is not available; in hospital, CURB-65 or PSI adds information.
  • Age alone gives 1 point, so many older adults score 1 without severe disease; judge oxygenation and comorbidity too.

Examples

crb65 70 year old, rr 26, bp 100/58, not confusedcrb-65 for 40F rr 18 bp 118/76pneumonia in clinic, 82 yo confused, resp rate 32

FAQ

What is the difference between CRB-65 and CURB-65?

CRB-65 omits the urea criterion so it can be used without blood tests; it is scored 0–4 instead of 0–5.

What CRB-65 score needs hospital referral?

Score 0 is usually managed at home; 1–2 warrants consideration of hospital assessment; 3–4 requires urgent admission.

Evidence

  1. Lim WS et al. Defining community acquired pneumonia severity on presentation to hospital. Thorax 2003;58:377–82.
  2. Bauer TT et al. CRB-65 predicts death from community-acquired pneumonia. J Intern Med 2006;260:93–101.

Pulmonary & Critical Care · Reviewed 2026-10-14 · Methodology