Statistical analyses
Data were analyzed with SPSS software version 25.0 for Windows (SPSS Inc, Chicago, Illinois). The Kolmogorov-Smirnov test was used to test whether the data were distributed normally. Continuous normally distributed variables are expressed by their mean and standard deviation. In multiple comparisons, one-way analysis of variance (ANOVA) test followed by the Tukey post hoc test was used for normally distributed continuous data. Nominal parameters were compared using Chi-square test. Pearson’s correlation test was used for correlation analysis. A multivariate linear regression model was used for analysis to determine the independent predictors of GFR. Statistical significance was defined as p<.05.