PulmonologyBeginner

CRB-65 Severity Score for Community-Acquired Pneumonia

Evaluates CRB-65 score (0–4) without blood urea to determine home treatment vs urgent hospital admission.

Clinical Parameters

4 Variables
Yes, this condition applies to the patient
Yes, this condition applies to the patient
Yes, this condition applies to the patient
Yes, this condition applies to the patient

Awaiting Clinical Parameters

Configure the patient variables on the left and select Calculate Result to generate the clinical score and stratification.

Verified 2026 GuidelinesInstant Calculation
Jump to Formula & Clinical Protocol ↓
High Yield Prometric TopicPulmonology

Tested on Gulf Medical Boards (DHA, SMLE, MOH & HAAD)

Clinical calculations and diagnostic scoring systems like CRB-65 Severity Score for Community-Acquired Pneumonia frequently appear on Prometric exams. Master high-yield clinical vignettes with instant AI-powered pathophysiology rationales.

Clinical Significance & Diagnostic Standard
2026 Clinical Reference

What is the CRB-65 Severity Score for Community-Acquired Pneumonia?

📋Clinical Summary & Definition Capsule

The CRB-65 Severity Score for Community-Acquired Pneumonia is an evidence-based clinical decision rule engineered to quantify diagnostic probability, stratify clinical severity, and guide therapeutic decision-making in pulmonology practice. Implements the British Thoracic Society (BTS) and NICE CRB-65 community pneumonia decision rule (Confusion, Respiratory rate, Blood pressure, Age ≥ 65) designed specifically for outpatient, primary care, and resource-limited settings without immediate lab access. Clinical scoring tools like CRB-65 Severity Score for Community-Acquired Pneumonia are essential in acute and outpatient management, enabling clinicians to objectively differentiate between low-risk candidates suitable for conservative therapy and high-risk patients requiring urgent interventions. Verified against current 2026 clinical standards, this tool is extensively tested on Gulf health authority licensing exams including DHA (Dubai), SMLE (Saudi Arabia), MOH, HAAD/DOH (Abu Dhabi), OMSB (Oman), and QCHP (Qatar).

💡Clinical Pearls & Diagnostic Utility

Empowers outpatient and primary care general practitioners to make rapid, evidence-based triage decisions without waiting for laboratory blood draws.

Mathematical Formulation

Formula & Calculation Parameters

The mathematical equation and clinical variables required to calculate CRB-65 Severity Score for Community-Acquired Pneumonia:

CRB-65 Score = Confusion (1) + Resp Rate ≥30 (1) + BP <90/<60 (1) + Age ≥65 (1)
Range: 0 to 4 points (No blood urea laboratory testing required)
Risk Stratification

Score Interpretation & Clinical Stratification

Score RangeClinical InterpretationRisk Tier
≤ 0Low Risk (Score 0: < 1.2% 30-Day Mortality / Outpatient Home Care)green
1 – 2Intermediate Risk (Score 1–2: 5–8% Mortality / Consider Hospital Admission)yellow
≥ 3High Risk (Score 3–4: 15–34% Mortality / URGENT HOSPITAL & ICU ADMISSION)red
Clinical Limitations & Contraindications

When to Exercise Caution

In emergency departments with rapid blood laboratories, CURB-65 (which includes Blood Urea Nitrogen) or PSI (PORT) provides higher discriminatory precision.

Medical Review & Guidelines Compliance
MD

Clinical Review Board

Dr. Muhammad Nouman, MBBS

Capital Medical University | PMDC Reg No: 117744-P

Clinical Audit Status

✓ Verified for 2026 Guidelines

Last updated: 2026-08-08

Peer-Reviewed Medical Literature

  • Lim WS, et al. Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study. Thorax. 2003;58(5):377-382.
  • National Institute for Health and Care Excellence (NICE). Pneumonia in adults: diagnosis and management (NICE Guideline CG191). 2019.