CRP and COVID-19: In this relatively simple severity and outcome prediction task, and with a small validation sample size and no external model evaluation, the authors have used the XGBoost classifier method to identify three biomarkers [namely, lactic dehydrogenase (LDH), lymphocyte count and high-sensitivity C-reactive protein (hs-CRP)] that will allow the prediction of the mortality of COVID-19 patients more than 10 days in advance with reportedly more than 90% accuracy.