Authors' objectives:

This report evaluates the safety, effectiveness and cost-effectiveness of international normalised ratio (INR) point-of-care testing in general practice

Authors' results and conclusions: Two studies were identified that met the eligibility criteria for the assessment of diagnostic performance of international normalised ratio point-of-care testing (INR POCT) in general practice compared with INR laboratory-based testing. One was a randomised cross-over trial (level II evidence) and the other was a case series (level IV evidence). Overall, there was no significant difference in diagnostic performance between POCT and laboratory testing in the two studies. However, in the cross-over trial, at high INR levels, the POCT levels were higher than those obtained using laboratory testing. The key outcome measures were time in the therapeutic range in the cross-over trial and mean INR level in the case series. The crossover trial was limited by a small sample size, resulting in low study power. If a diagnostic test is to be effective it needs to be accurate, management needs to change as a result of the test, and that change in management needs to be effective. There was support for change in management in response to abnormal INR levels. When the INR level is low there is an increased risk of thromboembolism and when it is high there is an increased risk of bleeding. Given the use of time in the therapeutic range as an intermediate outcome measure in the cross-over trial, the results can be linked to the risk of haemorrhagic or clinical events. Patient management was changed in this trial according to specific INR levels. However, overall there was little data on the use of INR POCT in general practice, with only two studies identified that fulfilled the eligibility criteria, and there was uncertainty about the diagnostic performance of POCT at high INR levels. The POCT trial currently underway in Australia may help to resolve these uncertainties.

Authors' recommendations: After consideration of safety, effectiveness and cost-effectiveness, there is insufficient evidence to support the use of INR point-of-care testing in general practice at this stage.

Authors' methods: Systematic Review

Project Status: Completed

URL for project: http://www.msac.gov.au/reports.htm

Year Published: 2005

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Australia

Organisation Name: Medical Services Advisory Committee

Contact Address: MSAC (MDP 107), GPO Box 9848, Canberra, ACT 2601, Australia. Tel: +61 2 6289 6811; Fax: +61 2 6289 8799.

Contact Name: msac.secretariat@health.gov.au

Contact Email: msac.secretariat@health.gov.au

Copyright: Medical Services Advisory Committee (MSAC)