Repeatability
56
Variation arising when all efforts are made to keep conditions constant by using
57
the same instrument and operator, and repeating during a short time period.
58
Expressed as the repeatability standard deviation (SD
r
); or % repeatability
59
relative standard deviation (%RSD
r
).
60
61
Reproducibility
62
The standard deviation or relative standard deviation calculated from among-
63
laboratory data. Expressed as the reproducibility relative standard deviation
64
(SD
R
); or % reproducibility relative standard deviation (% RSD
R
).
65
66
67
4.
Method Performance Requirements:
68
See Table 1.
69
70
Table 1. Method Performance requirements
a
71
Analytical range
1–1300
b
Limit of Quantitation (LOQ)
≤ 1
b
Recovery
90-110%
Repeatability (RSD
r
)
1-100
b
8%
>100-1300
b
5%
Reproducibility (RSD
R
)
1-100
b
15%
>100-1300
b
10%
a
Concentrations apply to: a) ‘ready-to-feed” liquids “as is”; b) re-
constituted powders (25 g into 200 g of water); and c) liquid
concentrates diluted 1:1 by weight.
b
μg /100 g reconstituted final product; range and LOQ are
based on total of
cis
+
trans
isomers.
72
73
5.
System suitability tests and/or analytical quality control:
74
Suitable methods will include blank check samples, and check standards at the
75
lowest point and midrange point of the analytical range. Methods must be capable of
76
resolving
β
-carotene from α-carotene and lycopene.
77
78
6.
Reference Material(s)
:
79
SRM 1869. Please contact Dr. Melissa Phillips, Research Chemist, NIST for materials at
80
melissa.phillips@nist.govor (301) 975-4134.
81
82
83
7.
Validation Guidance
:
84
Recommended level of validation:
Official Methods of Analysis
SM
.
85
86
8.
Maximum Time-To-Result
: No maximum time.
87
88