Statistical analysis
Statistical analyses were performed using SPSS version 23.0. Numeric
data are expressed as mean ± SD. Student’s t-test was used for
between-group comparisons. One-way analysis of variance with
Tukey–Kramer post hoc test was used to compare several quantitative
variables. Pearson’s correlation test was used to assess
between-variable correlations. Statistical significance was set at P
< 0.05.