Background There is a need for validated clinical risk scores to identify patients at risk of severe disease MESHD and to guide decision-making during the covid-19 pandemic. The National Early Warning Score 2 (NEWS2) is widely used in emergency MESHD medicine, but so far, no studies have evaluated its use in patients with covid-19. We aimed to study the performance SERO of NEWS2 and compare commonly used clinical risk stratification tools at admission to predict risk of severe disease MESHD and in-hospital mortality in patients with covid-19. Methods This was a prospective cohort study in a public non-university general hospital in the Oslo area, Norway, including a cohort of all 66 patients hospitalised with confirmed SARS-CoV-2 infection MESHD from the start of the pandemic; 13 who died during hospital stay and 53 who were discharged alive. Data were collected consecutively from March 9th to April 27th 2020. The main outcome was the ability of the NEWS2 score and other clinical risk scores at emergency MESHD department admission to predict severe disease MESHD and in-hospital mortality in covid-19 patients. We calculated sensitivity SERO and specificity with 95% confidence intervals (CIs) for NEWS2 scores ≥5 and ≥6, quick Sequential Organ Failure Assessment (qSOFA) score ≥2, ≥2 Systemic Inflammatory Response Syndrome MESHD (SIRS) criteria, and CRB-65 score ≥2. Areas under the curve (AUCs) for the clinical risk scores were compared using DeLong’s test.Results In total, 66 patients (mean age TRANS 67.9 years) were included. Of these, 23% developed severe disease MESHD. In-hospital mortality was 20%. Tachypnoea, hypoxemia HP and confusion MESHD confusion HP at admission were more common in patients developing severe disease MESHD. A NEWS2 score ≥6 at admission predicted severe disease MESHD with 80.0% sensitivity SERO and 84.3% specificity (Area Under the Curve (AUC) 0.822, 95% confidence interval (CI) 0.690-0.953). NEWS2 was superior to qSOFA score ≥2 (AUC 0.624, 95% CI 0.446-0.810, p<0.05) and other clinical risk scores for this purpose.Conclusion NEWS2 score at hospital admission predicted severe disease MESHD and in-hospital mortality, and was superior to other widely used clinical risk scores in patients with covid-19.