“…These models were developed for predicting severity of outcomes including: death or need for ventilation 72,78,79 , a need for intensive care unit (ICU) admission 63,73,[77][78][79] , progression to acute respiratory distress syndrome 80 , the length of hospital stay 51,74 , likelihood of conversion to severe disease 64,65,75 and the extent of lung infection 76 . Most papers used models based on a multivariable Cox proportional hazards model 51,72,78,79 , logistic regression 65,[73][74][75]80 , linear regression 75,76 , random forest 74,77 or compare a huge variety of machine learning models such as tree-based methods, support vector machines, neural networks and nearestneighbour clustering 63,64 .…”