CELL-DYN
®
3200 System Operator’s Manual
4-11
9140181H—October 2001
Section 4
Performance Characteristics and Specifications
Hemogram Parameters
Precision specifications for the hemogram parameters are presented using
coefficient of variation (CV).
The stated CV% in the following Table represents the instrument precision at a
95% confidence level from N = 20 replicate runs based on the same sample.
WBC Differential Parameters
Precision specifications for the WBC Differential parameters are given as a 95%
confidence limit for N=20 replicate runs based on the same sample.
This confidence limit represents the allowable difference (plus or minus) of the
individual results from the mean of the 20 determinations (runs). Specimens
selected for the precision study must have means that fall within the specimen
range listed in both tables.
These samples should not display any of the following suspect Parameter Flags:
WBC or DFLT.
To determine the 95% confidence limit of a parameter:
1. Find the value listed in the Confidence Limit column for that parameter.
2. Add that value to the mean to determine the upper limit.
3. Subtract that value from the mean to determine the lower limit.
For example, if the mean of the Neutrophil parameter is 50, the 95% confidence
limit is 47.8–52.2.
Table 4.8
Precision of the Hemogram Parameters (N = 20)
Parameter
Specimen Range
CV
WBC (WOC)
4.1–11.0 x K/
µL
< 2.7%
WBC (NOC)
4.1–11.0 x K/
µL
< 2.7%
RBC
4.0–6.0 x M/
µL
< 1.5%
HGB
12.1–17.0 g/d
L
< 1.0%
MCV
81.0–100.0 fL
< 1.0%
RDW
12.0–16.0%
< 5.0%
PLT
150.0–400.0 x K/
µL
< 4.0%
MPV
5.0–10.0 fL
< 5.0%
RETIC %
0.5–2.7%
< 15.0%
