QwikCheck™
Sperm Quality Analyzer Guide Version 1.00 I-Button WHO 5th 06_AUG_2012
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Method comparison:
SQA was compared to the microscope based on WHO 4TH
guidelines.
Sensitivity and specificity were calculated using ROC
curves. WHO 4TH guidelines were used to establish
cutoffs for reference values (see table #1).
218 of the 342 semen specimens contained motile cells
and were used as the basis for the method comparison
(Table #4).
SQA Linearity
Clinical claims:
Linear Sperm Concentration throughout the SQA
dynamic range of 2M/ml to 400M/ml:
Squared regression coefficient of Dilution Curve
R
2
≥0.9.
Averaged coefficient of variation CV of measured vs.
expected sperm concentration ≤ 20%.
Goal:
To demonstrate the ability of the SQA to accurately
report sperm concentration along the dynamic range of the
system using sequentially diluted human semen samples.
Methodology:
4 fresh human semen samples were pooled,
divided into two aliquots and centrifuged at 600g for 15
minutes. The seminal plasma was decanted and the pellets
were re-suspended in washing media: DPBS & HepesHTF.
Sequential dilutions were run in 4 SQA systems.
Limitations of method:
Dilution errors contribute to the accuracy of the
linearity test results.
Sample handling errors such as the introduction of
bubbles into the testing capillary can cause inaccurate
readings.
Table #3: Precision
Parameter
Range
Method
SQA
CV%
Microscope
CV%
Sperm
Concentration
M/ml
Entire Range
3.1
6.1
5-40
5.2
5.9
41-80
2.1
5.5
>80
2.5
3.2
Motility
%
Entire Range
5.1
7.2
10-50
7.6
10.3
51-55
1.5
3.4
>55
6.0
4.1
Table #4: Percentage Motile Cells Detected
Method Comparison of
218 Samples with
Motile Cells
# Samples
Motile Sperm
Detected
% Samples
Motile Sperm
Detected
SQA Automated
System and
Visualization System
207
95%
Visualization System
only
193
89%
Microscope only
161
74%
Results:
1.
Squared regression coefficient R
2
of Dilution Curve
(trend line) was found to be 0.992 (note graph
displaying results of four SQA’s and DPBS and Hepes
dilution media).
2.
Averaged coefficient of variation CV of measured vs.
expected sperm concentration was 10%.
