Table. 4. Table 4

Accelerated stability study results of candidate reference standards

Reference standard	Temperature (°C)	Recovery rate (%)				k	P of slope t-test

		1 week	2 weeks	3 weeks	4 weeks
MP/01	−20	103	103	104	104	0.001	< 0.05
	4	108	116	124	124	0.008	< 0.05
	24	118	126	130	131	0.009	< 0.05
	37	138	134	125	117	0.003	0.66
MP/02	−20	99	100	99	104	0.001	0.32
	4	111	113	114	117	0.005	< 0.05
	24	103	106	115	114	0.005	< 0.05
	37	116	109	103	94	−0.004	0.40
MP/03	−20	97	99	101	100	0.001	0.49
	4	101	101	103	105	0.002	< 0.05
	24	104	110	116	120	0.007	< 0.05
	37	122	122	122	117	0.004	0.32
MP/04	−20	101	100	102	100	0.000	0.91
	4	101	96	98	101	0.000	0.79
	24	97	96	96	95	0.002	< 0.05
	37	102	99	93	88	0.005	< 0.05
MP/05	−20	99	100	99	100	0.000	0.93
	4	100	103	105	105	0.002	< 0.05
	24	106	108	107	111	0.003	< 0.05
	37	121	121	116	118	0.004	0.32
MP/07	−20	100	102	99	100	0.000	0.93
	4	103	101	100	100	0.000	0.67
	24	98	101	105	111	0.004	0.04
	37	118	116	111	107	0.001	0.76
MP/08	−20	96	98	96	97	0.001	0.41
	4	98	97	101	101	0.001	0.48
	24	95	100	103	105	0.003	0.13
	37	115	109	98	87	−0.006	0.23
MP/09	−20	99	97	99	96	0.001	0.15
	4	100	102	102	102	0.001	0.08
	24	98	103	107	112	0.005	< 0.05
	37	112	110	105	99	−0.001	0.70
MP/10	−20	99	99	99	99	0.000	< 0.05
	4	100	97	98	100	0.000	0.68
	24	97	99	99	101	0.001	0.47
	37	102	102	101	102	0.000	0.52
MP/11	−20	105	105	103	103	0.001	0.45
	4	103	104	108	110	0.003	< 0.05
	24	115	116	119	119	0.006	0.08
	37	119	119	118	120	0.005	0.18

Abbreviations: k, degradation rate constant; MP, mixed-titer performance panel.