What is the Highest MEWS Score?
The Modified Early Warning Score (MEWS) ranges from 0 to a maximum theoretical score that varies by scoring system design, but the highest clinically relevant MEWS score documented in the literature is 15. 1
MEWS Score Range and Structure
MEWS is calculated from five physiological parameters: systolic blood pressure, pulse rate, respiratory rate, temperature, and level of consciousness, with each parameter assigned points based on degree of abnormality 2
The scoring system uses an aggregated weighted approach where progressively abnormal vital signs trigger higher scores and corresponding escalation of care 1
One guideline specifically references MEWS bands ranging from 0 to 15, indicating this as the upper limit of the scoring system used in clinical practice 1
Clinical Significance of Score Ranges
MEWS scores are typically stratified into bands (0-2,3-4,5-15) with different clinical implications and intervention triggers at each level 1
A MEWS score ≥5 at 24 hours is associated with significantly increased in-hospital mortality (sensitivity 78%, specificity 94%) and should prompt urgent clinical review 3
Scores in the 3-4 range showed significantly higher cardiac arrest rates in one study, though this finding was not consistent across all MEWS bands 1
Practical Application
The score can be calculated rapidly from routine ward observation data without requiring laboratory tests or electronic systems, making it practical for bedside use 1
Higher MEWS scores trigger escalating levels of intervention: scores of 5-6 should prompt urgent review by a clinician competent in acute care, while scores ≥7 require assessment by teams with critical care competencies 1
MEWS performs well for predicting major adverse events with an area under the curve of approximately 0.77-0.90 for mortality prediction, though composite scores like NEWS may have slightly better discrimination 1
Important Caveats
MEWS should not be used in isolation as a single tool for clinical decision-making; one study found that adding other criteria such as clinical concern ("worried") improved sensitivity for detecting patient deterioration 1
The score may underperform in certain populations: patients with meningitis or meningococcal sepsis can deteriorate rapidly despite initially reassuring early warning scores 1
Different institutions may use slightly modified versions of MEWS with varying maximum scores, so local protocols should specify the exact scoring system and thresholds used 1