COULTER HmX Hematology Analyzer, Reference Manual

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PN 4237523A 4-5
SPECIFICATIONS/CHARACTERISTICS
CBC AND DIFFERENTIAL PERFORMANCE SPECIFICATIONS
4
Accuracy
Accuracy is defined as agreement between test and reference values at any point within the
operating range.
CBC
Accuracy is referenced to a COULTER S-PLUS™ series instrument. See Table 4.3.
WBC Differential
To determine accuracy of the WBC differential, the binomial is set at a slope of 1.00. The 95%
confidence limits are based on the sum of the variances for an 800-cell reference differential
and the total instrument count representing random and process error. The reference
document is the NCCLS H20 (using an 800 cell count) specification.
Linearity
When tested using a stable sample having no interfering substances, the COULTER HmX
Hematology Analyzer values are equal to the expected values within the limits in Table 4.6.
To get these same results, subtract background counts from the HmX Hematology Analyzer
values and take multiple readings at each point to eliminate statistical effects of imprecision.
Linearity of size measurements (MCV and MPV) are tested using appropriate techniques.
Linearity limits apply only to directly measured parameters. See Table 4.4.
Table 4.2 Precision, WBC Differential Parameters
Parameter 95% Confidence Limits
LY% at 31; WBC at 4.0 x 10
3
cells/µL
±3.0
MO% at 8; WBC at 4.0 x 10
3
cells/µL
±2.0
NE% at 57; WBC at 4.0 x 10
3
cells/µL
±3.0
EO% at 3; WBC at 4.0 x 10
3
cells/µL
±1.0
BA% at 1; WBC at 4.0 x 10
3
cells/µL
±1.0
Table 4.3 CBC Accuracy Limits
Parameter Units Mean Difference: The greater of:
WBC
x 10
3
cells/µL
±0.2 or 3.0%
RBC
x 10
6
cells/µL
±0.05 or 2.0%
Hgb g/dL ±0.2 or 2.0%
MCV fL ±2.0%
Plt
x 10
3
cells/µL
±10.0 or 7.0%
MPV fL ±5.0%