Table 5.

Rheumatoid factor interference on high and low plasma pools.

Type of the plasma pool	Vol. of RF control serum (μL)a	Vol. of the plasma pool (μL)	RF conc. in plasma pool (IU/mL)	vWF LAT (titre)
High plasma pool	25	175	129	1 : 64
	30	180	147	1 : 128 (weak)
	40	200	172	1 : 128
Low plasma pool	10	990	10	1 : 2
	10	390	26	1 : 4
	10	190	52	1 : 8
	10	90	103	1 : 16
	10	70	129	1 : 32

  ^aRheumatoid factor control serum from MyBioSource, USA (1030 IU/mL), was used to spike plasma pools.

RF: rheumatoid factor; VWF LAT: von Willebrand factor latex agglutination test; vol., volume; conc., concentration.