2.9 Statistical analysis
All data are reported as mean ± standard deviation, For baseline comparisons, differences in means of continuous data between placebo and intervention groups will be evaluated using independent Student t test or Mann-Whitney U test depending on whether the data are normally distributed, and frequencies will be compared using Chi-square test. For longitudinal data with baseline, we will evaluate mean differences between and within groups using repeated measures analysis of covariance (ANCOVA). All tests will be two-tailed and Fisher ‘s exact rate method will be used to compare ratios between the two groups, with significance level defined as a value of 