Statistical Analysis
SAS (version 9.2; SAS Institute Inc) was used. Qualitative data are presented as n (%), and data were compared using a chi-square test. Continuous quantitative data conforming to normal distribution are presented as mean (SD), and values were compared using the method of repeated measurement analysis (ANOVA). Continuous quantitative data not conforming to normal distribution are presented as median (IQR), and values were compared at time 1 and time 3 using the Mann-Whitney 