Variables of different study groups of AKIN classification.

Descriptive statistics for categorical variables were expressed as frequency and percentage while continuous variables were reported as mean ± standard deviation or median (interquartile range) as appropriate.分类变量的描述性统计以频数与百分比形式呈现，连续变量则根据适宜情况报告为均值±标准差或中位数（四分位间距）。