COULTER HmX Hematology Analyzer, Reference Manual

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PN 4237523A 4-15
SPECIFICATIONS/CHARACTERISTICS
RETICULOCYTE PERFORMANCE CHARACTERISTICS
4
4.7 RETICULOCYTE PERFORMANCE CHARACTERISTICS
Imprecision Analysis by Replication
Imprecision is stated in terms of standard deviation (SD). The SD was determined by replicate
testing using 31 dilutions of the same whole blood specimen. The test was repeated at three
different reticulocyte levels. See Table 4.22.
Table 4.23 shows paired samples imprecision analysis.
n = 145, Test 1 vs. Test 2
Accuracy
Accuracy is shown by analysis of paired tests using clinical specimens. The analysis used the
conventional calculation method for Mean Difference and Standard Deviation of differences
(SD). Accuracy is defined as the degree of agreement between the reference method, NCCLS
H16-P, and the HmX Hematology Analyzer. Clinical specimens with values covering the
expected range of performance were used. Table 4.24 displays the results of the accuracy
analysis.
COULTER HmX Hematology Analyzer analysis based on 145 clinical specimens.
Table 4.22 Imprecision Analysis by Replication
Statistic Level I Level II Level III
Mean 0.22 1.54 6.72
SD 0.05 0.20 0.47
n 31 31 31
Table 4.23 Imprecision Analysis by Paired Samples
Criteria Mean Minimum Maximum
(A) Test 1 2.25% 0.20% 2.25%
(B) Test 2 2.31% 0.30% 2.31%
Difference (A-B) -0.06% N/A N/A
SD of Differences 0.43% N/A N/A
Table 4.24 Accuracy Analysis by Compared Specimens
Criteria Mean Minimum Maximum
(A) HmX Hematology Analyzer Reticulocyte Counter 3.43% 0.3% 26.50%
(B) Reference 3.26% 0.12% 24.06%
Difference (A-B) 0.19% N/A N/A
SD of Differences 1.01% N/A N/A