Table 2.

Sensitivity and specificity—HoloTC versus B₁₂—original research data

Reference	Sensitivity	Specificity	Cut-off	AUC
Bamonti et al. (2010)	0.74	0.52	HoloTC < 40 pmol/L	0.75
Clarke et al. (2007) (definite deficiency)	0.771 versus 0.757	0.761 versus 0.724	MMA > 0.75 μmol/L	0.85 versus 0.76
Clarke et al. (2007) (probable deficiency)	0.647 versus 0.626	0.792 versus 0.748	MMA > 0.45 μmol/L	0.79 versus 0.87
Goringe et al. (2006)			HoloTC < 38 pmol/L	0.75 versus 0.72
Heil et al. (2012)	0.83 versus 0.64	0.60 versus 0.64	MMA > 0.45 μmol/L	0.78 versus 0.70
Herrmann et al. (2003a)	0.87 versus 0.45	0.75 versus 0.98	MMA > 0.271 μmol/L	0.879 versus 0.836
Herrmann and Obeid (2013)	0.72 versus 0.72	0.54 versus 0.41	MMA > 0.300 μmol/L	0.714 versus 0.632
Hvas and Nexo (2003)	1.0	0.89
Hvas and Nexo (2005)			MMA > 0.75 μmol/L	0.90 versus 0.85
Lindemans et al. (2007)			MMA > 0.26 μmol/L	0.80 versus 0.68
Lloyd-Wright et al. (2003)			MMA > 0.75 μmol/L	0.87 versus 0.86
Miller et al. (2006)			holoTC < 35 pmol/L	0.828 versus 0.816
Obeid and Herrmann (2007a)	0.72		MMA > 0.300 μmol/L	0.71 versus 0.60
Palacios et al. (2013)	0.44 versus 0.20	0.94 versus 0.94	HoloTC < 35 pmol/L	0.75 versus 0.69
Schrempf et al. (2011)	0.563 versus 0.662	0.505 versus 0.621	MMA > 47 μg/L	0.66 versus 0.72
Scott et al. (2007)			MMA > 0.75 μmol/L	0.85 versus 0.75, 0.74, 0.72
Valente et al. (2011)	0.55 versus 0.33	0.96 versus 0.95	Red cell cobalamin <33 pmol/L	0.90 versus 0.80

Clarke et al. (2007) compared the HoloTC immunoassay to two assay methods for total vitamin B₁₂: Beckman and Centaur

Scott et al. (2007) compared the HoloTC immunoassay to three assay methods for total vitamin B₁₂: Beckman, Centaur and micro assays

AUC, area under ROC curve for HoloTC or total vitamin B₁₂; ROC curve, Receiver Operating Characteristic = sensitivity versus (1 − specificity) = true positive versus false positive (Miller et al. 2006); Cut-off, analyte and cut-off value used to define vitamin B₁₂ deficiency