CRP and appendicitis: The results are presented as mean ± SD or median (interquartile range, IQR). AA - acute appendicitis. Criterion - this value corresponds to the point on the receiver operating characteristic (ROC) curve farthest from the diagonal line; the possible threshold value with the highest specificity/sensitivity. AUC - Area under the ROC curve. Se - sensitivity. Sp - specificity. CRP - C-reactive protein. WBC - white blood cell count. RBC - red blood cell count. RDW - red cell distribution width. PLT - platelets. MPV - mean platelet volume. P < 0.05 was considered statistically significant.