The Modified Early Warning Score (MEWS) is a clinical scoring system designed to detect early signs of patient deterioration and guide timely interventions. It was developed to support decision-making in general hospital wards by using vital sign abnormalities to predict the risk of adverse outcomes such as cardiac arrest, unplanned intensive care admission, or death.

MEWS evaluates five key parameters: systolic blood pressure, heart rate, respiratory rate, temperature, and level of consciousness (AVPU: Alert, Voice, Pain, Unresponsive). Each parameter is scored from 0 to 3 depending on how far it deviates from the normal range. The scores are summed, yielding a total MEWS that can range from 0 upward, with higher scores reflecting greater physiological instability.

The main strength of MEWS lies in its simplicity and clinical utility. It allows healthcare providers, including nurses and junior doctors, to quickly recognize changes in patient status. Evidence suggests that routine monitoring using MEWS can reduce delays in escalation of care and improve patient outcomes. It also provides an objective way to trigger rapid response team activation or more frequent monitoring, depending on hospital protocols.