Statistica for windows

A Kolmogorov-Smirnov and Shapiro-Wilk normality tests were applied for data distribution analysis. Spearman’s rank correlations and Mann-Whitney U-test were used to non-normally distributed data which was expressed as median (quartiles). The receiver operating characteristic (ROC) curve analyses are presented as the areas under the curve (AUCs) and the 95% confidence intervals (CIs). The diagnostic efficacies of the gene expression values were assessed using the sensitivities and specificities at the cut-off points. Logistic regression was used to model the relationship between expression of the examined genes prior to surgery and postoperative pain preservation six months after surgery. The logistic regression model was built using the stepwise inclusion method. To compare percentages, a two-tailed Z-test for percentages was applied. Statistica for Windows and Statistical Package for the Social Sciences (SPSS) version 19 software (IBM, Armonk, NY, USA) were used for all of the statistical analyses. p-values ≤ 0.05 were considered significant.

Spearman’s rank correlations and the Mann–Whitney U-test were used to analyze non-normally distributed data, which were expressed as medians (Me) [quartiles, IQR]. A receiver operating characteristic (ROC) curve analysis included calculating the area under the curve (AUC) and the 95% confidence interval (CI). The diagnostic efficacy of the gene expression values was assessed using the sensitivity and specificity at the cut-off point. To compare percentages, a two-tailed Z-test for percentages was applied. Statistica for Windows and Statistical Package for the Social Sciences (SPSS) version 19 software (IBM, Armonk, NY, USA) were used for all the statistical analyses. p-values ≤ 0.05 were considered significant.