COVID-19 Evidence Alerts
from McMaster PLUSTM

Current best evidence for clinical care (more info)

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Clinical Prediction Guide Richardson D, Faisal M, Fiori M, et al. Use of the first National Early Warning Score recorded within 24 hours of admission to estimate the risk of in-hospital mortality in unplanned COVID-19 patients: a retrospective cohort study. BMJ Open. 2021 Feb 22;11(2):e043721. doi: 10.1136/bmjopen-2020-043721.

OBJECTIVES: Although the National Early Warning Score (NEWS) and its latest version NEWS2 are recommended for monitoring deterioration in patients admitted to hospital, little is known about their performance in COVID-19 patients. We aimed to compare the performance of the NEWS and NEWS2 in patients with COVID-19 versus those without during the first phase of the pandemic.

DESIGN: A retrospective cross-sectional study.

SETTING: Two acute hospitals (Scarborough and York) are combined into a single dataset and analysed collectively.

PARTICIPANTS: Adult (=18 years) non-elective admissions discharged between 11 March 2020 and 13 June 2020 with an index or on-admission NEWS2 electronically recorded within ±24 hours of admission to predict mortality at four time points (in-hospital, 24 hours, 48 hours and 72 hours) in COVID-19 versus non-COVID-19 admissions.

RESULTS: Out of 6480 non-elective admissions, 620 (9.6%) had a diagnosis of COVID-19. They were older (73.3 vs 67.7 years), more often male (54.7% vs 50.1%), had higher index NEWS (4 vs 2.5) and NEWS2 (4.6 vs 2.8) scores and higher in-hospital mortality (32.1% vs 5.8%). The c-statistics for predicting in-hospital mortality in COVID-19 admissions was significantly lower using NEWS (0.64 vs 0.74) or NEWS2 (0.64 vs 0.74), however, these differences reduced at 72hours (NEWS: 0.75 vs 0.81; NEWS2: 0.71 vs 0.81), 48 hours (NEWS: 0.78 vs 0.81; NEWS2: 0.76 vs 0.82) and 24hours (NEWS: 0.84 vs 0.84; NEWS2: 0.86 vs 0.84). Increasing NEWS2 values reflected increased mortality, but for any given value the absolute risk was on average 24% higher (eg, NEWS2=5: 36% vs 9%).

CONCLUSIONS: The index or on-admission NEWS and NEWS2 offers lower discrimination for COVID-19 admissions versus non-COVID-19 admissions. The index NEWS2 was not proven to be better than the index NEWS. For each value of the index NEWS/NEWS2, COVID-19 admissions had a substantially higher risk of mortality than non-COVID-19 admissions which reflects the increased baseline mortality risk of COVID-19.

Discipline / Specialty Area Score
Hospital Doctor/Hospitalists
Internal Medicine
Infectious Disease
Intensivist/Critical Care
Comments from MORE raters

Intensivist/Critical Care rater

Strengths: • Large dataset used. • Both medical and surgical admission compared. Weaknesses: • While Covid-19 can affect the surgical population, the significance of that is much less compared to medical patients. • Mortality of surgical patients mainly depends on the surgical factors than covid-19 issues. • Oxygen supplementation in surgical patients is used routinely. Many surgical patients will need ventilation for surgical indications. • Subgroup analysis between medical and surgical patients missing. • No explanation was given why c-statistics predicted lower mortality in covid-19 patients. • Progression of NEWS should have been used. • Increasing oxygen requirements surprisingly did not have any impact on NEWS/NEWS2 values. Impression: Timely survey of the impact of NEWS on Covid-19. But this should have included mainly surgical patients or the authors should have done subgroup analysis to differentiate impact between medical and surgical patients.