MEWS Calculator — Modified Early Warning Score
The Modified Early Warning Score (MEWS) is a validated physiological scoring system used to identify hospitalized patients at risk of clinical deterioration and trigger appropriate escalation of care.
About
The Modified Early Warning Score (MEWS) aggregates five physiological parameters: heart rate, systolic blood pressure, respiratory rate, temperature, and level of consciousness (AVPU). Developed by Subbe et al. in 2001, MEWS is designed to be simple and quick for bedside use by nursing staff. Scores ≥5 are associated with increased risk of ICU admission, cardiac arrest, or death within 60 days. MEWS triggers a graded response: low scores (0-2) continue routine monitoring; moderate (3-4) increase monitoring frequency; high (5-6) require urgent medical review; and very high (≥7) mandate immediate critical care team involvement. The score is part of a broader rapid response system approach.
Formula
MEWS = HR points + SBP points + RR points + Temp points + AVPU points
Each of the 5 parameters is scored on a scale of 0-3. Heart rate ≤40 scores 2, 41-50 scores 1, 51-100 scores 0, 101-110 scores 1, 111-129 scores 2, ≥130 scores 3. Systolic BP ≤70 scores 3, 71-80 scores 2, 81-100 scores 1, 101-199 scores 0, ≥200 scores 2. Respiratory rate ≤8 scores 2, 9-14 scores 0, 15-20 scores 1, 21-29 scores 2, ≥30 scores 3. Temperature ≤35 scores 2, 35.1-36 scores 1, 36.1-38 scores 0, 38.1-38.5 scores 1, ≥38.6 scores 2. AVPU: Alert 0, Voice 1, Pain 2, Unresponsive 3.
Score Interpretation
MEWS is a widely implemented track-and-trigger system that enables early recognition of patient deterioration. Studies show that implementation of MEWS systems reduces cardiac arrests and unplanned ICU admissions by 20-30%.
Low Risk (0-2) — 0–2
Routine monitoring per clinical protocol.
Management: Continue standard vital sign monitoring.
Moderate Risk (3-4) — 3–4
Increased monitoring. Inform charge nurse.
Management: Increase monitoring frequency and consider medical review.
High Risk (5-6) — 5–6
Urgent medical review required.
Management: Immediate physician assessment and consider HDU/ICU transfer.
Very High Risk (≥7) — 7+
Critical care team involvement needed.
Management: Immediate critical care review, continuous monitoring, and prepare for ICU transfer.
Reference Ranges
| Population | Normal Range | Notes |
|---|---|---|
| General ward adult patients | MEWS 0-2: low risk | MEWS ≥5 associated with increased mortality |
Dr. Khaled Hassan
Dr. Khaled is a cardiology consultant with experience in acute cardiac care.
View medical review board & editorial policy →Example Calculation
A 70-year-old patient: HR 110 (1 pt), SBP 85 (2 pts), RR 24 (2 pts), Temp 38.2°C (1 pt), AVPU alert (0 pts). MEWS = 1+2+2+1+0 = 6. High risk — urgent medical review needed.
Related Conditions
Common Mistakes
Using MEWS in isolation without clinical judgment
MEWS is a screening tool that complements clinical judgment. A deteriorating patient with low MEWS score still warrants assessment if clinical concern exists.
Frequently Asked Questions
What is the difference between MEWS and qSOFA?
References
- Subbe CP, Kruger M, Rutherford P, Gemmel L. Validation of a modified Early Warning Score in medical admissions. QJM. 2001;94(10):521-526. PubMed
- NICE Guideline: Acutely ill adults in hospital: recognising and responding to deterioration (CG50, 2007, updated 2024).