Statistical analysis
The study evaluated children’s clinical and demographical characteristics based on their CRP levels above or below the median. Results from the univariate analysis were presented as mean ± SD for normally distributed variables or as a median with interquartile range (IQR) for variables not meeting the normal distribution assumption. Categorical variables were presented as counts and proportions of available data. Differences in quantitative variables between groups were analyzed using ANOVA or the nonparametric Wilcoxon rank sum test. Categorical parameters were compared using Chi-squareχ2 or Fisher’s exact test. Quasi-Poisson regression modeling was used for multivariable analysis to investigate the association between the CRP value and clinical outcomes. The optimal cutoff values for CRP were determined using Youden’s index with the R pROC package. The predictive ability of these cutoffs for severe clinical outcomes was evaluated using the receiver operating characteristic curve (ROC), and the area under the curve (AUC) was calculated to measure this ability. Statistical significance was indicated by a P value of 0.05 in all analyses. All statistical analyses were performed using R software (version 4.0.2), developed by the R Foundation for Statistical Computing, in Vienna, Austria (http://www.R-project.org).