43 / 48
AOAC INTERNATIONAL
Memorandum
Date: December 13, 2016
To:
Statistics Working group on Intermediate Precision
From: Scott Coates
Intermediate Precision [ RSD
i
]
1.
Should AOAC specify/include Intermediate precision in method evaluations?
a.
Required in Appendix L:
AOAC Recommended Guidelines for Stakeholder Panel on Infant
Formula and Adult Nutritionals (SPIFAN) Single-Laboratory Validation (attachment 1)
b.
Required or optional in validation manuscript ?
c.
In place of RSDr, or in addition to RSDr ?
d.
In SMPRs ?
2.
Which definition to use?
a.
Appendix K:
Guideline for Dietary Supplements and Botanicals
includes a definition
(attachment 2) but does not provide guidance for evaluation.
b.
Specific minimum requirements (minimum number of analysts, instruments, days, etc.)
3.
Expected value?
a.
Predicted RSDr is estimated as 2/3 * (PRSDR) .
b.
PRSDR = 2C^
–
0.15.
c.
Predicted RSD
i
?
4.
In which document should this guidance reside ?