RADIOMETER ABL800 FLEX, Reference Manual

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5. Performance characteristics ABL800 FLEX Reference Manual
Definition of terms and test conditions
General
information Performance specifications are achieved by comparison between the ABL800
FLEX analyzers and the primary reference methods, and by comparison between
the ABL800 FLEX analyzers and the ABL735.
Performance specifications of the ABL800 FLEX analyzers are described, using
the following:
•
Bias
Ref
= the mean difference between the ABL800 FLEX and the primary
reference methods.
•
Bias
ABL
= the mean difference between the ABL800 FLEX and the ABL735.
•
Repeatability
•
Reproducibility
•
Total variation range
•
Imprecision.
Bias The bias of a quantity is defined as the mean difference between the measured
value on a group of test instruments and the estimated true value (as assayed by the
reference method). Bias
Ref
is determined as follows:
Bias
Ref
= X
ABL800 FLEX
−
X
Primary Reference method
Bias
ABL
is a relative bias between the ABL835 in FLEXMODE and the ABL735 in
C195
µ
L mode, and is determined as follows:
Bias
ABL
= X
ABL800 FLEX
−
X
ABL735
Repeatability
Samples, assumed to be identical, repeatedly measured on one analyzer will not
necessarily yield identical results. The degree of variation in the results is a
measure of the repeatability of the analyzer.
The repeatability is obtained from repeated measurements within a short interval of
time using:
•
The same instrument and location
•
The same measurement procedure
•
Identical portions of the same sample
•
One operator per instrument
The repeatability for each level is pooled for all test instruments and test days.
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