How to Calculate CRB-65 Score

The CRB-65 Score is a clinical prediction rule for assessing the severity of community-acquired pneumonia (CAP) based on 30-day mortality risk. It is a simplified version of CURB-65, omitting urea measurement. The score is the sum of points from four criteria:

• Confusion (new disorientation): +1
• Respiratory rate ≥30 breaths/min: +1
• Low blood pressure (SBP <90 mmHg or DBP ≤60 mmHg): +1
• Age ≥65 years: +1

Total score ranges from 0 to 4. Select Yes/No for each criterion and calculate.

Note: Used for adults with CAP; not for children or nosocomial pneumonia.

Using the CRB-65 Score Calculator

This calculator helps clinicians decide on outpatient vs. inpatient treatment for pneumonia patients. It's quick and doesn't require lab tests.

Select presence of each criterion. The calculator outputs the score and risk interpretation.

Example 1: No confusion, RR 25, BP 100/70, Age 50.

1. Confusion: No
2. RR ≥30: No
3. Low BP: No
4. Age ≥65: No
5. Score: 0
6. Interpretation: Low risk; consider home treatment

Example 2: Confusion yes, RR 32, BP 85/55, Age 70.

1. Confusion: Yes
2. RR ≥30: Yes
3. Low BP: Yes
4. Age ≥65: Yes
5. Score: 4
6. Interpretation: High risk; urgent hospital admission

Use in conjunction with clinical judgment.

Common FAQ

Below are frequently asked questions about CRB-65 Score:

• Q: What is the CRB-65 Score?
  A: A tool to predict 30-day mortality in community-acquired pneumonia and guide treatment setting.
• Q: How does it differ from CURB-65?
  A: CRB-65 omits blood urea nitrogen, making it usable without labs.
• Q: What are typical mortality rates?
  A: Score 0: ~0.7%, 1-2: ~3-9%, 3-4: ~17-30%.
• Q: Is it validated?
  A: Yes, studies show it's comparable to PSI and CURB-65 for predicting mortality.
• Q: Can it be used for all patients?
  A: Primarily for adults with CAP; use caution in immunocompromised or other special cases.

Advice on Interpreting Results

The CRB-65 helps stratify risk but should not replace clinical judgment. Consider comorbidities, social factors, and patient preference.

For score 0: Outpatient treatment usually safe.

For 1-2: May need brief hospitalization or close outpatient follow-up.

For 3-4: Admit to hospital, consider ICU if score 4 or unstable.

British Thoracic Society recommends CRB-65 for initial assessment in primary care.