ITC ProTime Microcoagulation System - Manual (Page 23)

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Clinical Performance Comparison
A. ProTime3 vs. ProTime
Linear regression containing clinical fingerstick results from three sites yielded a regression equation
as below:
y = 1.02x - 0.14 r = 0.94 n = 229
B. Patient Self-Testing
In a trial of patient self-testing (PST) in the home vs. professional testing in the clinical and reference
lab, equivalent ProTime results were obtained.
ProTime Professional vs. Patient Self-Testing
y = .94x + 0.13 r = 0.92 n = 421
ProTime Patient Self-Testing vs. Reference Lab
y = .77x + 0.38 r = 0.87 n = 368
Sensitivity
ProTime is sensitive to deficiencies in vitamin K-dependent coagulation factors known to influence the PT
test (i.e., Factors II, VII and X.)
Hematocrit levels between 20% and 60% do not significantly affect test results.
Quality Control
The ProTime instrument has been designed with multiple systems to ensure proper instrument function.
The instrument self-check at startup checks temperature and timing functions, battery level, and optical,
electrical and mechanical functions. The instrument does not require further calibration. Each ProTime
cuvette has two integral reagent controls that ensure assay reliability and performance. Both levels of
control produce quantifiable clotting endpoints that are compared to pre-set acceptance limits programmed
in the instrument.
Other in-process instrument QC features and the integral reagent controls function together to ensure
correct sample size and collection technique, correct test procedure, instrument functionality and reagent
integrity. A fault message is displayed instead of PT results when any instrument or reagent quality criterion
is not met. When a fault message is displayed, the user should review the product instructions and repeat
the test.
Additional external control materials may be used to check instrument function, reagent integrity and user
technique. Each institution should establish a quality assurance program for prothrombin time testing that
complies with existing local, state and federal regulations as applicable.
As with all diagnostic tests, the ProTime Microcoagulation System test results should be scrutinized in light
of a specific patient's condition and anticoagulant therapy. Any results exhibiting inconsistency with the
patient's clinical status should be repeated or supplemented with additional test data.
TECHNICAL ASSISTANCE
For further information and technical assistance, contact ITC Technical Support at 1-732-548-5700,
1-800-631-5945, or e-mail us at [email protected].