Statistical analysis
Statistical analysis was performed using SPSS software version 22. All
data were expressed as mean ± standard deviation or percentage as
appropriate. To evaluate differences between groups, the unpaired
student’s t test for continuous variables and the chi-square test/fisher
exact test for categorical variables was used, as appropriate. We
calculated a receiver-operating characteristic (ROC) analysis and report
sensitivity and specificity for time and re-exploration. The area under
the ROC curve (AUC) was the overall performance measure of the accuracy
of the test. A stepwise logistic regression was performed to evaluate
independent markers associated with re-exploration and mortality. A p
value of <0.05 (for a two-sided test) was considered
significant.