Spss software package version 13 for windows

All statistical analyses were performed using SPSS software package, Version 13 for Windows (SPSS Inc, Chicago, IL). A chi‐squared test (χ²) was used to analyze the categorical variables. Continuous data were reported as mean ± standard deviation (range). Volume and VRR of the ablation area before RFA and at each follow‐up were analyzed by the t test. The Wilcoxon signed rank test was used to compare tumor calcification, color Doppler flow imaging (CDFI) blood flow grades, and changes in the number of patients with tumor disappearance at each follow‐up between CLT+PTMC and PTMC groups. The Wilcoxon rank sum test was used to compare Free T3, T4, and TSH values in patients with and without CLT P values <0.05 were considered statistically significant.

All statistical analyses were performed using SPSS software package, Version 13 for Windows (SPSS Inc., Chicago, IL, USA). A chi-squared test (χ²) was used to analyze the categorical variables. When the total observed frequency was less than 40 or the theoretical frequency was less than 1, Fisher's exact probability test was used instead of a χ² test. Kruskal-Wallis test was used to analyze the significant difference among the means of three or more independent groups when the data did not obey the normally distributed variables and homogeneity of variance. A kappa test was used to measure the agreement between two reviewers' diagnoses. Kappa < 0.4 was considered as a poor agreement, 0.4 < kappa < 0.75 was a moderate agreement, and kappa > 0.75 was a good agreement. P values less than 0.05 were considered statistically significant.

The relative mRNA levels were analyzed with SPSS for Windows software package version 13.0 (SPSS, Inc., Chicago, IL, USA). All data were presented as the mean ± standard deviation (SD) for continuous variables. The Student’s t-test was used if the data have a normal distribution. Otherwise, the Kruskal–Wallis test was used. A two-sided p-value < 0.05 was taken as the level for statistical significance. ROC analysis was performed to explore the predictive accuracy of hub genes in the GSE15774 database. AUC was used to evaluate the sensitivity and specificity of each gene. The genes with an AUC of more than 0.7 and p-value of less than 0.05 were used to evaluate the predictive accuracy of hub genes (Fang et al., 2021 (link); Kang et al., 2021 (link)).