Monte Carlo simulation
To determine the factors that contribute to the clinical outcome at the population level, Monte Carlo simulation was performed on a sample set of laboratory and clinical parameters covering the full range, from asymptomatic to severe disease, of outcomes (stages 1-7 [Figure 2]) [12, 13]. The histogram and cumulative data (Figure 3a)show the distribution of asymptomatic to severe outcomes. The Tornado chart (Figure 3b ) shows the sensitivity of parameter to the outcome in the selected range.