2 / 3
Repeatability
54
Variation arising when all efforts are made to keep conditions constant by using
55
the same instrument and operator, and repeating during a short time period.
56
Expressed as the repeatability standard deviation (SD
r
); or % repeatability
57
relative standard deviation (%RSD
r
).
58
59
Reproducibility
60
The standard deviation or relative standard deviation calculated from among-
61
laboratory data. Expressed as the reproducibility relative standard deviation
62
(SD
R
); or % reproducibility relative standard deviation (% RSD
R
).
63
64
65
4.
Method Performance Requirements:
66
See Table 1.
67
68
Table 1. Method Performance requirements
a
69
Analytical range
1–50
b
Limit of Quantitation (LOQ)
≤ 1
b
Recovery
90-110%
Repeatability (RSD
r
)
8%
Reproducibility (RSD
R
)
15%
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
70
71
5.
System suitability tests and/or analytical quality control:
72
Suitable methods will include blank check samples, and check standards at the
73
lowest point and midrange point of the analytical range. Methods must be capable of
74
resolving α-carotene from lycopene and
β
-carotene.
75
76
6.
Reference Material(s)
: Neither NIST nor JRC produce a certified reference material for
77
α-carotene in infant formula.
78
79
7.
Validation Guidance
:
80
Recommended level of validation:
Official Methods of Analysis
SM
.
81
82
8.
Maximum Time-To-Result
: No maximum time.
83
84
85