Table 3.

Potency estimates relative to 16/138 for U.S. reference reagent Vi-IgG_{R1, 2011} and coded samples A to E.

Method	Sample	GMa								Overall GM	Inter-lab GCVb	Intra-lab GCV
		Laboratory code	1	2	3	4	5	6	7
NIBSC ELISA	Vi-IgGR1, 2011		2.80	–	–	3.50	2.61	3.75	1.80	2.80	31%	22%
	A		1.34	–	–	1.47	1.62	1.70	1.15	1.44	16%	10%
	B		0.73	–	–	0.77	0.74	1.03	0.73	0.79	15%	11%
	C		0.85	–	–	0.92	0.90	1.21	1.07	0.98	15%	13%
	D		0.46	–	–	0.50	0.66	0.25	0.25	0.39	54%	20%
	E		0.33	–	–	0.39	0.38	0.43	0.60	0.42	25%	10%
VaccZyme ELISA	Vi-IgGR1, 2011		1.60	2.02	1.60	1.59	1.39	1.63	–	1.63	11%	13%
	A		0.84	1.04	1.18	1.09	1.23	1.21	–	1.09	15%	10%
	B		0.27	0.48	0.47	0.41	0.31	0.39	–	0.38	24%	9%
	C		0.70	0.97	1.01	1.08	0.94	1.22	–	0.97	20%	11%
	D		0.21	0.18	0.25	0.31	0.31	0.29	–	0.25	24%	14%
	E		0.44	0.60	0.65	0.71	0.66	0.69	–	0.62	19%	13%
In-house ELISA	Vi-IgGR1, 2011		1.88	–	–	1.89	1.70	5.18	–	–	–	–
	A		0.93	–	–	1.17	1.09	1.51	–	–	–	–
	B		0.46	–	–	0.41	0.53	1.25	–	–	–	–
	C		1.04	–	–	1.01	0.90	1.15	–	–	–	–
	D		0.22	–	–	0.33	0.23	0.14	–	–	–	–
	E		0.68	–	–	0.66	0.47	0.42	–	–	–	–

-: No data entered.

GCV≥25%: Font in Bold.

^aGM: Geometric Mean.

^bGCV: Geometric Coefficient of Variation.