Table 2.

Results of the QCMD 2006 Epstein-Barr Virus Proficiency Program

Sample no.	Viral load (log copies/ml)
	QCMD expected results	R-gene assay	Delta log (R-gene − QCMD)*	In-house PCR	Delta log (in-house − QCMD)*
EBV06-01	3.00	3.05	0.05	2.89	−0.11
EBV06-02	4.00	3.51	−0.49	3.61	−0.39
EBV06-03	2.40	Negative	ND†	(2.10)‡	−0.30
EBV06-04	2.00	(1.58)	−0.42	(1.81)	−0.19
EBV06-05	3.40	2.93	−0.47	3.09	−0.31
EBV06-06	3.00	(1.40)	−1.60	(2.33)	−0.67
EBV06-07	2.40	2.51	0.11	(1.69)	−0.71
EBV06-08	3.70	2.57	−1.13	3.58	−0.12
EBV06-09	Negative	Negative	ND	Negative	ND
EBV06-10	2.70	(2.48)	−0.22	(2.39)	−0.31

^*Delta log, the log copies/ml difference between R-gene or in-house PCR assays and QCMD panels.

^†ND, not determined.

^‡Values in parentheses are below the limit of quantification of both tests.