Table 2. Mean Change in Assay Results by Number of Freeze Thaw Cycles Prior to Testing.

Number of freeze thaw cycles prior to testing		3		7		15
	N	Mean Change (SD)	N	Mean Change (SD)	N	Mean Change (SD)
BED assay (OD-n)	31	−0.04 (±0.23)	30	−0.01 (±0.23)	12	−0.01 (±0.23)
Vironostika-LS assay (SOD)	31	0.02 (±0.41)	31	−0.01 (±0.42)	8	−0.05 (±0.50)
Avidity assay (%)	31	1.39 (±7.48)	30	1.86 (±5.84)	8	−4.02 (±12.7)
SD: Standard Deviation.

Mean Change in Assay Results by Number of Freeze Thaw Cycles Prior to Testing.

SD: standard deviation; OD-n: normalized optical density; SOD standardized optical density.