Statistical analysis
Data were analyzed using STATISTICA 13.1 (SatSoft, Kraków, Poland) and Medcalc 19.1 (MedCalc Software, Ostend, Belgium). Figures were prepared in GraphPad Prism version 8 (GraphPad Software, San Diego, CA). Data were presented as medians and interquartile ranges (IQR). We performed chi-square test or Fisher’s exact test for qualitative variables, and Kruskall-Wallis test or Mann Whitney test for quantitative variables. Changes in IFN-γ and IP-10 concentrations during treatment were assessed using Wilcoxon signed rank test. The Spearman’s rank test was applied to assess biomarker correlation. The diagnostic performance of IP-10 was assessed using the receiver operating characteristic curve (ROC) analysis and the area under the curve (AUC). The highest values of the Youden’s Index were used for selecting the cut-off values. The TB antigen and mitogen control concentrations of IP-10 were background-corrected by subtracting the concentration in the negative control tube. All tests were two-sided, and a p value of <0.05 was considered significant.
RESULTS: