Statistical analysis Statistical analysis will be performed using Statistical Product and Service Solutions(SPSS) 18.0 software, with normally distributed variables expressed as mean ± standard deviation; abnormally distributed variables as median and interquartile range; and categorical variables expressed as number and percentage. Continuous variables will be compared among groups using Student's t-test. Abnormally distributed data will be compared among groups using non-parametric Mann-Whitney U test. Categorical variables will be compared among groups using Chi-square test or Fisher's exact test. Repeated measure analysis of variance (ANOVA) will be performed for the different time point assessments between groups. P < 0.05 will be considered significant.