COULTER HmX Hematology Analyzer, Справочное руководство

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PN 4237523A 4-7
SPECIFICATIONS/CHARACTERISTICS
RETICULOCYTE PERFORMANCE SPECIFICATIONS
4
Carryover
The effect of sample A on the values obtained for the next sample, sample B, is less than 2.0%
when the analysis is based on 10 determinations and when calculated:
where B is the error in B due to carryover.
4.4 RETICULOCYTE PERFORMANCE SPECIFICATIONS
Precision
Within-Run Imprecision (total system). Validation limits for 31 separately prepared dilutions
of the same specimen are:
Run-to-Run Precision. Validation of paired imprecision for reticulocytes is based upon the
differences of Run 1 and Run 2 specimens. The limits over the clinical range of a minimum of
50 specimens from a general hospital population of no more than 30% abnormally elevated
reticulocyte specimens (Retic >4%) are as follows:
Paired imprecision limits over the clinical range for a minimum of 50 specimens with the
following characteristics are:
r
Greater than 50% abnormally elevated Retic values (Retic >4%).
r
No greater than 5 of 50 specimens have Retic values >20%.
* Both requirements must be met.
Accuracy
Reticulocyte parameter accuracy is the sum of the variables of linearity and imprecision for
the test, and the comparator method using specimens covering the reportable range. The
reference method for reticulocyte counting is described in the NCCLS document H16-P (n =
4,000) or its pertinent successor document. Analysis is based on the differences [diff = Run 2
(instrument) - Reference].
% carryover
∆
B
A
-------- 100
×
=
Limits (Whichever is greater)
RET% SD Limit CV Limit
<1.00 <0.23
≤
23%
1.00 - 4.00 <0.23
≤
17%
4.01 - 15.00+ <0.68
≤
15%
Parameter Mean Difference* SD of Difference*
RET% ±0.4
≤
0.8
Parameter Mean Difference* SD of Difference*
RET% ±0.5
≤
1.5