Fig. 4.

Pretransplant ROC curve analysis, cut‐off, AUC, sensitivity and specificity values for the percentage of activated CD4⁺CD154⁺ and CD8⁺CD154⁺ T cells in LTr. (a) The AUC^˩ value determined a cut‐off^ǂ ≥ 3·18% of activated CD4⁺CD154⁺ T cells that accurately stratified LTr at high risk of ACR. (b) The AUC^˩ value determined a cut‐off^ǂ < 0·8% of activated CD8⁺CD154⁺ T cells that accurately stratified LTr at high risk of ACR.^‡ AUC = area under the curve; 95% CI = 95% confidence interval; ROC = receiver operating characteristic curve; LTr = liver transplant recipients; ACR = acute cellular rejection. ^˩AUC = values considered in this study: 0·7–0·8 as acceptable; 0·8–0·9 as excellent and > 0·9 as outstanding. Both AUC values were considered excellent. ^‡Youden index (sensitivity + specificity – 1) was carried out to obtained the most accurate cut‐off values, represented by the arrow, capable to stratify patients at high risk of ACR for the pretransplant percentages of activated CD4⁺CD154⁺ and CD8⁺CD154⁺ T cells. ^†Statistically significant P <0·05 is denoted in bold type.