Statistical analysis
GraphPad Prism8.0 software (San Diego, CA, USA) was used to analyzed data. Continuous variables were expressed as standard deviation (SD) or median and interquartile range (IQR) according normal or non-normal distribution, respectively. Comparison between two normal distribution groups was performed by two-tailed unpaired t test with Welch’s correction. The correlation of two groups with normal distribution was computed by Pearson correlation analysis, while non-normal distribution was calculated by Spearman correlation analysis. In order to perform the multiple factors correlation analysis, the variables in the univariate analysis with p -value less than 0.10 and no multicollinearity were included. Multicollinearity was judged according to the condition indexes and the variance ratio in the fitted equation. p -values less than 0.05 were considered statistically significant.