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3.4
Test evaluation / calculation
3.4.1
Mechanical measurements (ball method)
The procedure of establishing the test value itself is always the same for all tests which have to
be carried out with the mechanical method. The time from adding the start reagent until clot
formation, through which the ball is pulled away from its basic position, is measured. In general
the measured time is converted into a parameter-specific unit whereas the graduation of the
measure axes in the conversion coordinate system can be different.
Furthermore the measured time of the PT can also be converted to the INR-value. Therefore it is
necessary to have either the INR-standard value which can be calculated by means of a self-
established calibration curve or the by the MC 10
plus
suggested value which is calculated by
means of the entered calibration curve. This value is displayed in brackets in the test parameters
after the input for the INR-standard. Also the analyser-specific ISI-value which is stated on the
reagent package insert is required for the INR-calculation.
The calculation is carried out as follows:
( )
Example: calibration curve PT
(axes graduation log/log)
1
10
100
1
10
100
percent %
se
co
nd
s
measured time of the test material
INR-standard value
INR=
ISI
Summary of Contents for MC10 PLUS
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