Performance Characteristics: Carryover; Performance Characteristics: Analytical Range - Siemens ADVIA 2120 Operator's Manual

Parameter
% MN
% PMN
% Neut
% Lymph
% Mono

Performance Characteristics: Carryover

Because of the low number of cells counted in CSF analysis, the ADVIA 120
hydraulic cycles were designed to eliminate carryover when assaying CSF
samples. Prior to assaying each CSF sample, the ADVIA120 rinses all reagent
and sample pathways in preparation for the next sample. Carryover for the CSF
Assay was evaluated by measuring multiple assays of a highly cellular sample
followed by a low cellular sample. The observed carryover was less than 1%,
where carryover is expressed as the average percentage of the high level sample
that is lost to the trailing low level sample.

Performance Characteristics: Analytical Range

The analytical range for CSF WBC and RBC counts was established by making
serial dilutions of samples prepared to have low analyte values. The dilution
studies show that the CSF WBC count is accurate to 5 cells/μL over the range
0–50 cells/μL and accurate to 10% over the range 50–5,000 cells/μL. The CSF
RBC count is accurate to 5 cells/μL over the range 0–50 cells/μL and accurate to
10% over the range 50-2880 cells/μL. The results from the study are found in the
tables below.
CSF WBC Low Level Linearity
Pool
(% of reference level)
0.00%
0.05%
0.1%
0.2%
1.0%
10.0%
100% (reference level)
Regulatory Information
Manual ADVIA 120
Mean Mean
72.7 72.2
26.9 25.6
26.6 22.3
63.2 54.6
9.5 17.6
Observed
WBC
0
2
5
10
53
514
5009
t-test % Within
p-value Binomial Limit
0.992 100%
0.800 100%
0.383 98%
0.088 96%
0.15 96%
Expected Absolute
WBC Deviation
0 0
3 -1
5 0
10 0
50 3
501 13
5009 0
%
Deviation
3
0
9-43