Statistical analysis
REGRESSION
Follow-up data were collected by a physician and a statistician who were blinded
to the treatment groups. Mean and standard deviation was used to express
continuous variables. The baseline characteristics of the patients in both
groups were reported using descriptive statistics, such as frequency
distributions, central tendency, and measures of distribution. Student's t-test
was used for normally distributed numerical variables, the chi-square test was
used for categorical variables, and the Mann–Whitney U test was used for
non-parametric variables. The adjusted odds ratios (ORs) with 95% confidence
intervals were presented as the results of the multivariate logistic regression
analysis. Statistical significance was set at P < 0.05. Statistical analyses
were performed using JMP 11 software (SAS Institute Inc., Cary, NC, USA).