Table 4.

Test characteristics based on optimal cut-off values for iron deficiency, determined by ROC curve analysis and comparison between AUC^ROC for MCH, Iron, TSAT and ferritin, respectively, and AUC^ROC for hepcidin

Variable	Sensitivity (%)	Specificity (%)	ROC area	Cut-off	PV+ (%)	PV- (%)	p
MCH	56	89	0.78	28 pg	83	67	0.22
Iron	73	74	0.63	6.5 μmol/L	73	73	0.03
TSAT	70	74	0.74	14.5%	73	71	0.11
Ferritin	91	83	0.93	87 μg/L	84	90	0.58
Hepcidin	100	67	0.90	21 μg/L	75	100	–

ROC receiver operating characteristics, MCH mean corpuscular haemoglobin, TSAT transferrin saturation, PV+ positive predictive value, PV negative predictive value