Table 2.

Interference testing with chyle, hemoglobin, bilirubin, rheumatoid factor, and EDTA- 2Na.

Interfering substances	Concentrations	Mean % difference in concentration
		sPD-1	sPD-L1	sCTLA-4
Chyle	1660 FTU	−1.2	1.3	−2.6
Hemoglobin	4900 mg/L	1.4	1.8	−0.6
Free bilirubin	200 mg/L	1.5	−1.4	−3.1
Ditauro-bilirubin	200 mg/L	0.0	0.0	−0.4
Rheumatoid factor	500 IU/mL	−1.4	1.4	−1.3
EDTA-2Na	5000 ug/mL	−0.2	0.3	−3.9