Test strip qualification system

• US 6,849,456 B2
• Filed: 11/12/2003
• Issued: 02/01/2005
• Est. Priority Date: 03/14/2002
• Status: Expired due to Term

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Lifescan Incorporated (Duv Holding Corporation)
• Inventors: Patel, Harshad, Witt, James
• Primary Examiner(s): WALLENHORST, MAUREEN
• Application Number:
  US10/712,680
• Publication Number:
  US 20040106212A1
• Time in Patent Office: 447 Days
• Field of Search: 436/8, 436/63, 436/69, 436/180, 422/73, 422/100, 435/13, 600/368, 600/369, 73/644.1, 702/19, 702/31, 702/32
• US Class Current: 436/8
• CPC Class Codes: G01N 33/4905 Determining clotting time of blood by chemical methods G01N33/86, C12Q1/54
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10T 436/10 Composition for standardization, calibration, simulation, stabilization, preparation or preservation; processes of use in preparation for chemical testing
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

In connection with a fluidic medical diagnostic device that permits measurement of the coagulation time of blood, software, methods and associated devices for quality control are provided. The fluidic device preferably includes a test strip with one end having a sample port for introducing a sample and a bladder at the other end for drawing the sample to a measurement area. A channel carries sample from the sample port to an assay measurement area and first and second control measurement areas. Preferably a stop junction, between the measurement areas and bladder, halts the sample flow for measurement. If results from measurements taken for each control fall within a predetermined zone or defined limits, the assay measurement is qualified. If not, an error is registered and the test strip is counted as unfit.

Claims

1. A system for testing the qualification of a test strip for use to measure prothrombin (PT) time, said test strip comprising an assay reaction area and a control reaction area, said system comprising:

a meter configured for receiving said test strip; and

a computer-readable medium embodying a program to qualify said test strip according to a method comprising;

obtaining PT results for said control reaction area; and

comparing results from said control reaction area to control qualification criteria comprising an upper limit and a lower limit, said upper limit being about a 1.9 International Normalized Ratio and said lower limit being about a 0.60 International Normalized Ratio, wherein said test strip is qualified if said results fall within said upper limit and said lower limit.

2. The system of claim 1, wherein said Program further comprises outputting a message to a user indicating test strip qualification.

3. A system for testing the qualification of a test strip for use to measure prothrombin (PT) time, said test strip comprising an assay reaction area and a control reaction area, said system comprising:

a meter configured for receiving said test strip; and

a computer-readable medium embodying a program to qualify said test strip according to a method comprising;

obtaining PT results for said reaction areas; and

comparing results from said control reaction area to control qualification criteria comprising an upper limit and a lower limit, each being dependent on assay reaction area PT results, wherein said test strip is qualified if said results fall within said upper limit and said lower limit.

4. The method of claim 3, wherein said upper and lower limits comprise line functions.

5. The method of claim 4, wherein said line functions are expressed as y=m×

+b, wherein y represents an International Normalized Ratio results obtained for said control reaction area, ×

represents an International Normalized Ratio results obtained for said assay reaction area and m≈

0.56 to 0.58 and b≈

0.90 for said upper limit and wherein m ≈

0.36 and b ≈

0.37 to 0.38 for said lower limit.

6. The system of claim 5, wherein said program further comprises outputting a message to a user indicating test strip qualification.

7. A system for testing the qualification of a test strip for use to measure prothrombin (PT) time, said test strip comprising an assay reaction area, a first control reaction area and a second control reaction area, said system comprising:

a meter configured for receiving said test strip; and

a computer-readable medium embodying a program to qualify said test strip according to a method comprising;

obtaining PT results for each said reaction areas; and

comparing results from said first control reaction area to first control qualification criteria comprising a first upper limit and a first lower limit, said first upper limit being about a 1.9 International Normalized Ratio and said first lower limit being about a 0.60 International Normalized Ratio; and

comparing results from said second control reaction area to second control qualification criteria comprising a second upper limit and a second lower limit, each being dependent on assay reaction area PT results;

wherein said test strip is qualified if said results from said first control reaction area fall within said first upper limit and said first lower limit and if said results from said second control reaction area fall within said second upper limit and said second lower limit.

8. The system of claim 7, wherein said program further comprises outputting a message to a user indicating test strip qualification.