LAUSR

S TATIS TIC AL ANALYSE S Statistical analysis was performed with SPSS version 26.0 (IBM Corp., Armonk, NY), as appropriate. Data are presented as mean ± standard deviation (SD), unless stated otherwise. Normality of distribution was assessed with Kolmogorov-Smirnov test, and variables, including 25(OH)D and CRP levels as well as respiratory rate, WCC and lymphocyte count were logarithmically transformed for comparisons, if not normally distributed. Between-group comparisons were assessed with independent t test or Mann-Whitney U test in case of two groups, and Analysis of Variance and/or Kruskal-Wallis test in case of three or more groups. Associations between continuous variables were computed using Pearson’s or Spearman’s correlation coefficient and chi-square in case of categorical variables. Logistic regression models adjusting for age, gender, presence of co-morbidities and CRP levels were used to identify predictors of outcomes. Level of statistical significance was set at 0.05.