2.9 Statistical analysis
Data are expressed as percentages for the nominal variables, medians for the ordinal variables, and means for the continuous variables. Discrete variables were compared using the chi-square or Fisher exact test as appropriate. ROC curves were used to determine the LGE-entropy and LGE-volume ratio that provided the best sensitivity and specificity for the NPAs. A value of p < 0.05 was considered statistically significant. All statistical analyses were performed using SPSS, Release 24 software (SPSS, Chicago, IL, USA).
Results