Statistical analyses
Continuous data are presented as means ± standard deviations for
normally distributed variables or as median and interquartile range for
non-normally distributed variables. Categorical data are presented as
absolute values and frequencies (%). Comparative analyses
for the MBP and MMP groups were performed using Fisher’s exact or
Chi-square test for categorical variables and Student’s t-test or
Mann-Whitney U test for continuous variables, as appropriate. P
values < 0.05 were considered statistically
significant. All statistical analyses were performed using IBM SPSS 20
(IBM, USA). We used Cox proportional hazard models to analyze the
competing risk data and Fine and Gray cumulative incidence
function-based proportional hazard competing risk regression model to
analyze survival data.[11]