Modified Early Warning Score (MEWS) Identifies Critical Illness among Ward Patients in a Resource Restricted Setting in Kampala, Uganda: A Prospective Observational Study

PLoS One. 2016 Mar 17;11(3):e0151408. doi: 10.1371/journal.pone.0151408. eCollection 2016.


Introduction: Providing optimal critical care in developing countries is limited by lack of recognition of critical illness and lack of essential resources. The Modified Early Warning Score (MEWS), based on physiological parameters, is validated in adult medical and surgical patients as a predictor of mortality. The objective of this study performed in Uganda was to determine the prevalence of critical illness on the wards as defined by the MEWS, to evaluate the MEWS as a predictor of death, and to describe additional risk factors for mortality.

Methods: We conducted a prospective observational study at Mulago National Referral Teaching Hospital in Uganda. We included medical and surgical ward patients over 18 years old, excluding patients discharged the day of enrolment, obstetrical patients, and patients who self-discharged prior to study completion. Over a 72-hour study period, we collected demographic and vital signs, and calculated MEWS; at 7-days we measured outcomes. Patients discharged prior to 7 days were assumed to be alive at study completion. Descriptive and inferential statistical analyses were performed.

Results: Of 452 patients, the median age was 40.5 (IQR 29-54) years, 53.3% were male, 24.3% were HIV positive, and 45.1% had medical diagnoses. MEWS ranged from 0 to 9, with higher scores representing hemodynamic instability. The median MEWS was 2 [IQR 1-3] and the median length of hospital stay was 9 days [IQR 4-24]. In-hospital mortality at 7-days was 5.5%; 41.4% of patients were discharged and 53.1% remained on the ward. Mortality was independently associated with medical admission (OR: 7.17; 95% CI: 2.064-24.930; p = 0.002) and the MEWS ≥ 5 (OR: 5.82; 95% CI: 2.420-13.987; p<0.0001) in the multivariable analysis.

Conclusion: There is a significant burden of critical illness at Mulago Hospital, Uganda. Implementation of the MEWS could provide a useful triage tool to identify patients at greatest risk of death. Future research should include refinement of MEWS for low-resource settings, and development of appropriate interventions for patients identified to be at high risk of death based on early warning scores.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Critical Illness / mortality*
  • Early Diagnosis
  • Female
  • Health Status Indicators
  • Hospital Mortality
  • Hospitalization / statistics & numerical data*
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Prospective Studies
  • Risk Factors
  • Severity of Illness Index*
  • Uganda
  • Vital Signs*
  • Young Adult

Grant support

The authors received no specific funding for this work. The oximeters used for the study were donated by ProResp, Inc. The funder played no role in the design, data collection, analysis, interpretation, or write-up of this study. Dr. Crowther is funded by the Heart and Stroke Foundation of Canada. Dr. Cook holds a Research Chair of the Canadian Institutes of Health Research.