In this study, 10 independent clinical predictors were identified and used to develop a risk score (COVID-GRAM) that predicts development of critical illness from COVID-19. 

• Study took place in China: A retrospective cohort of patients with COVID-19 was established as a development cohort of 1590 patients. Data from 4 additional Chinese cohorts was used to create a validation cohort of 710 patients
• Outcome targeted for prediction was critical illness,  defined as the composite measure of admission to the intensive care unit, invasive ventilation, or death.
• From 72 potential predictors, 10 variables were independent predictive factors and were included in the risk score:
  • Chest radiographic abnormality (OR, 3.39; 95% CI, 2.14-5.38)
  • Age (OR, 1.03; 95% CI, 1.01-1.05)
  • Hemoptysis (OR, 4.53; 95% CI, 1.36-15.15)
  • Dyspnea (OR, 1.88; 95% CI, 1.18-3.01)
  • Unconsciousness (OR, 4.71; 95% CI, 1.39-15.98)
  • Number of comorbidities (OR, 1.60; 95% CI, 1.27-2.00)
  • Cancer history (OR, 4.07; 95% CI, 1.23-13.43)
  • Neutrophil-to-lymphocyte ratio (OR, 1.06; 95% CI, 1.02-1.10)
  • Lactate dehydrogenase (OR, 1.002; 95% CI, 1.001-1.004)
  • Direct bilirubin (OR, 1.15; 95% CI, 1.06-1.24)
• The accuracy of COVID risk score was determined by an area-under-the-curve (AUC) value, which was 0.88 (95% CI, 0.84-0.93) in the validation cohort
• The score has been translated into an online risk calculator that is freely available to the public (http://118.126.104.170/)