Statistical analysis
SPSS software (version 22.0) was used to perform the statistical
analyses. Categorical variables were reported as frequencies and
percentages, and were analyzed using χ2 tests.
Continuous variables were analyzed using the Student’s t test or
Mann-Whitney U test, where appropriate. The receiver operating
characteristic (ROC) curve analysis was utilized to determine the
optimal cut-off values of inflammatory predictors with MedCalc 17.6. The
area under the ROC curve (AUC) was used to compare prognostic factors.
The multivariate logistic regression analysis was performed on the
factors that were shown to be significant on univariate logistic
analysis. Odds ratio (OR) and 95% confidence intervals (CIs) were
utilized to evaluate relative risk. All tests were two-sided and
P<0.05 was considered to indicate a statistically significant
different.