Statistical analysis
Statistical analysis was performed using IBM SPSS, version 26. We tested
the correlation of NO serum to APACHE II and SAPS II scoring in
predicting the patients’ outcomes. Student’s t test (continuous
variable) and Fisher’s exact test (categorical variable) were used for
comparisons between survivors and non-survivors. Spearman rank
correlation was used to establish interrelationships between the
different variables. For each predictor variable, sensitivity and
specificity were calculated using Fisher’s exact test. Receiver
operating characteristic curve (ROC) was plotted using 1‐specificity on
X‐axis (false‐positive fraction [FPF]) and sensitivity
(true‐positive fraction [TPF]) on Y‐axis for all the predictor
variables.