2.6 Statistical analysis
SNP alleles and genotypes were described in terms of absolute number and percentage. Hardy-Weinberg equilibrium (HWE) analysis was performed using Pearson’s chi-square test. A web-based platform, SHEsis, was used to perform LD and haplotype analyses (http://analysis.bio-x.cn/myAnalysis.php). Risk assessment, odds ratio (OR) and its 95% confidence interval (CI), was estimated using age- and gender-adjusted multinomial logistic regression analysis, which was performed under five genetic models; allele, recessive, dominant, over-dominant, and co-dominant. Median and IQR were used to express continuous variables because they did not follow a normal distribution (‎Shapiro-Wilk and Kolmogorov–Smirnov tests), and Mann-Whitney U test was used to assess significant differences. The discriminatory performance of serum IFIH1 levels between patients and HC were evaluated using receiver-operating characteristic (ROC) curve analysis, which was presented in terms of area under the curve (AUC), 95% confidence interval, cut-off point (adjusted with Youden index; YI), sensitivity, and specificity. Correlation coefficient (rs) was determined using Spearman’s rank-order correlation analysis. The level of significance was set at a probability (p ) of less than 0.05, which was corrected (pc ) for multiple comparisons with the Bonferroni correction method or the false discovery rate method. Statistical analysis was performed using IBM SPSS Statistics 25.0 (Armonk, NY: IBM Corp.) and graphs were generated using GraphPad Prism version 9.2.0 (San Diego, CA, USA).