Statistical Analysis

Continuous variables were given as mean±SD or median values with interquartile range depending on normality of the variables. Categorical variables were presented as percentages. Comparisons for continuous data were performed using Student t‐test or one‐way ANOVA. Categorical variables were compared using the chi‐square test or Fisher exact test. Correlations were assessed by the Pearson or Spearman rank correlation coefficient. Receiver operating characteristics analysis was used to define the optimal cut‐off values. The intraclass correlation coefficient was used to assess the inter‐ and intra‐observer variability. All statistical analyses were conducted by using a statistical software package SPSS, Version 24.0 (IBM, SPSS Statistics). A 2‐tailed P<0.05 was considered statistically significant.