2.4. Statistical analysis
This was a double-center, double-blind, randomized, controlled clinical trial. According to previously reported,Statistical analysis was performed using the Statistical Package for the Social Sciences version 25.0 (IBM Corp., Armonk, NY). Categorical data are described as the frequency or percentage, and were compared with Chi-squared test or fisher exact test. The mean ± standard deviation was used for the description of quantitative data with normal distribution. Furthermore, 1-way analysis of variance was used comparisons among groups, and Tukey method was used for the comparison between groups. For quantitative data without normal distribution or with heterogeneity of variance, comparisons were performed using the Kruskal–Wallis H rank-sum test, and pairwise comparisons were performed using the Nemenyi method. A value of 