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QwikCheck™
Sperm Quality Analyzer Guide Version 1.00 I-Button WHO 5th 06_AUG_2012
25
Precision and accuracy established in clinical trials
using human semen samples
Clinical claims:
Specificity
 Concentration: 85%
 Motility: 80%
 Morph. Norm Forms (WHO 3
rd
): 65%
 Morph. Norm Forms (WHO 4
TH
): 60%
 Postvasectomy: 95% of motile cells detected
Sensitivity
 Concentration: 90%
 Motility: 85%
 Morph. Norm Forms (WHO 3
rd
): 85%
 Morph. Norm Forms (WHO 4
TH
): 65%
Correlation to Manual Method
 Concentration: 0.9
 Motility: 0.85
 Morph. Norm Forms (WHO 3
rd
): 0.65
 Morph. Norm Forms (WHO 4
th
strict): 0.45
Linearity
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%.
Note: Claims are less than actual correlations noted (see
tables 1 and 2)
Background: The SQA concentration, motility and
morphology readings were compared to standard
microscopic readings using a Makler or Neubauer chamber
based on WHO 4TH standards and MES protocols. Three
independent clinical trials were conducted at three sites. A
total of 539 human semen samples were analyzed as
described below: 342 samples were of low quality and were
tested in the High Sensitivity mode.
Precision (Table #3): Duplicate samples were assessed
using 2 SQA’s. The coefficients of variation (CV)
characterizing precision were calculated for Sperm
Concentration and Motility and were below 6%.
Specificity:
 To achieve analytical specificity a specific wave length of
light which is maximally absorbed by sperm cells and
minimally absorbed by other cells and seminal plasma is
used.
 Low noise and high electronic resolution hardware
components and compensation circuits ensure that
analytical specificity is optimized.
Limitations of clinical specificity:
 Highly viscous samples cannot be read accurately unless
treated with QwikCheck Liquefaction.
 % Normal Morphology is a parameter derived from the
correlation between morphology and progressive motility.
This is not a direct measurement.
 Dynamic range limitation as stated above.
#Samples Fresh Washed Frozen
High
Sensitivity
539 125 42 30 342
Limitations of method:
Samples were assessed by different operators using a
microscope and the SQA. Inter-operator subjectivity may
have affected the results of the study.
Table 1: Sensitivity/Specificity
SQA vs.
Microscope
Sensitivity Specificity
Trial #1:
Concentration 100% 95%
Motility 97% 85%
Morph Norm
Forms (WHO
3
rd
)
94% 75%
Trial #2:
Concentration 94% 90%
Motility 87% 90%
Morph Norm
Forms (WHO
4
th
)
69% 70%
Trial #3: High Sensitivity* (see table#4)
Motile Sperm
Cells
95% 95%
Immotile
Sperm Cells
99% 100%
Table #2: Correlation to Manual Method
Parameters
Correlation Coefficients
Trial #1 Trial #2
Sperm Concentration
M/ml
0.93 0.94
Motility % 0.86 0.87
Morphology WHO 3
rd
0.66 NA
Morphology WHO 4
th
NA 0.49
MSC NA 0.79