Data analysis
Data obtained were coded and entered into the Statistical
Package for Social Sciences (SPSS) version 11.0 (SPSS Inc.,
Chicago, IL, USA). Significance of differences in means and
proportions were tested using t-test and chi-square test,
respectively. Logistic regression and general linear model
analysis methods were used to adjust for differences in
baseline characteristics between the two groups concerning
categorical and numerical outcomes, respectively. The level
of statistical significance was set at 5%.