Serum Sclerostin and Its Association with Bone Turnover Marker in Metabolic Bone Diseases

Table 1

The performance characteristics of the methods for all measured biomarkers.

	Precision	Sensitivity	Reference intervals
PTH	Intra-assay ≤ 2.0%, inter-assay ≤ 3.4%	LOD: 1.20 pg/mL	15–65 pg/mL
25OHD	Intra-assay ≤ 6.8%, inter-assay ≤ 13.1%	LOB: 2 ng/ml; LOD: 3 ng/ml; LOQ: 5 ng/ml	> 20 ng/ml
Pi	Intra-assay ≤ 4%, inter-assay < 6%	:	0.8–1.6 mmol/L
ALP	Intra-assay ≤ 3.4%, inter-assay ≤ 4.1%	/min: (120 U/L): 0.020–0.100	15–112 U/L
β-CTX	Intra-assay ≤ 4.7%, inter-assay ≤ 5.7%	LOD: 10 ng/L	278–540 ng/L[38]
OC	Intra-assay ≤ 1.3%, inter-assay ≤ 2.3%	LOD: < 0.50 ng/mL	13.07–27.68 ng/mL[38]
Cr	Intra-assay ≤ 5.0%, inter-assay ≤ 10.0%	ΔA: (100.0 μ Mol/L): 0.003-0.040	53.0–115.0 μ Mol/L
Ca	Intra-assay ≤ 3%, inter-assay ≤ 5%	:	2.08-2.60 mmol/L
Sclerostin	Intra-assay ≤ 1%, inter-assay ≤ 5%	LOD: (0 pmol/L +3 SD):1.9 pmol/L; LLOQ: 1.3 pmol/L	Median serum: 61.5 pmol/L

PTH: parathyroid hormone; 25OHD: 25-hydroxyvitamin D; Pi: serum phosphate; ALP: serum alkaline phosphatase; β-CTX: β-CrossLaps of type 1 collagen containing cross-linked C-telopeptide; OC: serum osteocalcin in the form of an N-terminal midmolecule fragment; Cr: serum creatinine; Ca: serum total calcium; LOD: limit of detection; LOB: limit of blank; LOQ: limit of quantitation; LLOQ: lower limit of quantitation; : absorbance difference.