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Deep Vein ThrombosisOPTIMALNCT03682419

Evaluation of Precision and Accuracy of INR Measurements in a Point of Care Device

An observational study of Deep Vein Thrombosis and Atrial Fibrillation, run by LumiraDx UK Limited at 3 sites in United Kingdom.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Comparison of capillary whole blood INR determined by LumiraDx Instrument to venous plasma INR determined by laboratory reference method (IL ACL ELITE PRO) for method comparison and assessment of accuracy and bias by regression analysis and other analytical methods. Read more about this study

Who is it for?
Ages 18 years and older
What is being tested?
VKA Patients and Non-VKA Patients
Type of treatment
Surgery or procedure
How many people
420 participants
Where
3 sitesUnited Kingdom
Study dates
17 Sep 2018to 23 Nov 2018
Phase
Observational
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Study population: Capillary and venous whole blood samples were collected and analyzed from adult males and females who are receiving current vitamin K antagonist therapy and fulfil all other study inclusion and exclusion criteria. A subsection of the subject population (~50 subjects) consisted of adult males and females who fulfil all other study inclusion criteria but are not in receipt of vitamin K antagonist therapy. This was done in order to test the lower measurement range of the LumiraDx Instrument.

Who may be able to join

  • Persons >18 years of age
  • Willing and able to provide written informed consent and comply with study procedures
  • Currently prescribed vitamin K antagonist therapy
  • Deemed medically appropriate for study participation by the Investigator
  • Persons >18 years of age
  • Willing and able to provide written informed consent and comply with study procedures
  • Deemed medically appropriate for study participation by the Investigator

Who cannot join

  • Persons <18 years of age
  • Subject has previously participated in this study
  • Subject is within 4 weeks of first prescription of vitamin K antagonist therapy
  • Confirmed or suspected pregnancy
  • Unwilling or unable to provide written informed consent and comply with study procedures
  • Vulnerable populations deemed inappropriate for study by the Investigator
Show all 13Show fewer
  • Deemed medically inappropriate for study by the Investigator (i.e. patients with a known inherited [e.g. haemophilia or von Willebrand's disease] or acquired [e.g. liver cirrhosis] condition likely to be associated with a coagulopathy; or patients receiving non-VKA anticoagulant medications)
  • Persons <18 years of age
  • Subject has previously participated in this study
  • Confirmed or suspected pregnancy
  • Unwilling or unable to provide written informed consent and comply with study procedures
  • Vulnerable populations deemed inappropriate for study by the Investigator
  • Any persons deemed medically inappropriate for study by the Investigator

Trial locations and contacts

3 sites in 1 country.

United Kingdom3 sites
  • Glasgow Royal Infirmary Clinical Research Facility

    Glasgow, G4 0SF

  • Golden Jubilee National Hospital

    Glasgow, G81 4DY

  • Wishaw General Hospital, NHS Lanarkshire

    Wishaw, ML2 0DP

Other trials in United Kingdom

About this study

Official title: Evaluation of the Precision and Accuracy of International Normalised Ratio (INR) Measurements as Assessed by the LumiraDx Instrument in a Professional Point of Care Setting With Multiple Operators

Comparison of capillary whole blood INR determined by LumiraDx Instrument to venous plasma INR determined by laboratory reference method (IL ACL ELITE PRO) for method comparison and assessment of accuracy and bias by regression analysis and other analytical methods.

Read the detailed description

A performance evaluation study designed to assess the precision and accuracy of the LumiraDx Instrument, a point of care in vitro diagnostic system employing a portable diagnostic meter in conjunction with single use analyte test strips, for the quantitative determination of Prothrombin Time expressed as International Normalised Ratio (INR), as sampled from individuals evaluated for INR at the point of care (POC).

The accuracy of the LumiraDx Instrument INR results will be assessed by, in the first instance, comparison to the INR results obtained from the same individuals as analysed by trained laboratory professionals using the paired venous plasma samples in the reference device IL ACL ELITE PRO Coagulation Analyzer. The accuracy of INR measurements of capillary whole blood across the range of haematocrit (25% - 55%) will be assessed using paired haematocrit results obtained from the HemoCue Hb 201+ on venous whole blood. The results of these evaluations are intended to be used for regulatory filings for the LumiraDx Instrument and LumiraDx INR test as an in vitro diagnostic test in the European Union (EU) and other relevant geographies. For information only, the accuracy of the LumiraDx Instrument INR Test will also be assessed by comparison to INR results from an alternative point of care instrument, the Roche Coaguchek PRO II.

Adult males and females currently in receipt of vitamin K antagonist therapy will be included on the study. Approximately 500 subjects will be recruited to ensure that sufficient suitable subjects are enrolled and to allow for a small level of exclusions. The power calculation as well as recommendations of the FDA CLIA Waiver Guidance document (1) requires a minimum of 360 valid subjects in total (inclusive of non-therapy subset). A subsection of the subject population (~50 subjects) will consist of adult males and females who fulfil all other study inclusion criteria but are not in receipt of vitamin K antagonist therapy. This will be done in order to test the lower measurement limit of the LumiraDx Instrument INR test. At the end of the study the Healthcare Professional will be asked to complete a User Acceptability Questionnaire which is intended to assess the acceptability of the LumiraDx INR system in terms of ease of use.

Being tested
VKA Patients, Non-VKA Patients
Medical subject headings
Venous Thrombosis, Atrial Fibrillation, Donath-Landsteiner hemolytic anemia, Pulmonary Embolism, Thrombophilia, Antiphospholipid Syndrome

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • VKA PatientsProcedure or surgery

    Also called Fingerstick to collect blood samples from Patients, Venepuncture to collect blood samples from Patients

    Venepuncture and capillary blood collection from Patients receiving Warfarin Therapy

  • Non-VKA PatientsProcedure or surgery

    Also called Fingerstick to collect blood samples from Patients, Venepuncture to collect blood samples from Patients

    Venepuncture and capillary blood collection from Patients not receiving Warfarin Therapy

Study groups in NCT03682419
Study groupRoleWhat they receive
VKA PatientsSingle Arm - blood collection by venepuncture and fingerstick in patients undergoing Warfarin Therapy
Receives: Procedure: VKA Patients; Procedure: Non-VKA Patients
non-Vka PatientsSingle Arm - blood collection by venepuncture and fingerstick in patients not undergoing Warfarin Therapy
Receives: Procedure: VKA Patients; Procedure: Non-VKA Patients

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. To determine the clinical performance of the LumiraDx instrument

    Measurement of INR using Capillary \& Venous blood samples

    Measured: 8 weeks

Secondary outcomes (1)
  1. To determine the accuracy of the LumiraDx instrument

    Measurement of INR \& Haematocrit using Capillary \& Venous blood samples

    Measured: 8 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted24 Sep 2018
  2. Study start17 Sep 2018
  3. Primary completion23 Nov 2018
  4. Study completion23 Nov 2018

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Other
Time perspective
Prospective
Enrolment
420 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT03682419
Sponsor's protocol ID
D-CLIN-PROT-00001
Acronym
OPTIMAL
Status last verified
Jun 2026
First submitted
19 Sep 2018
Last updated
11 Jun 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Tait RC, Hung A, Gardner RS. Performance of the LumiraDx Platform INR Test in an Anticoagulation Clinic Point-of-Care Setting Compared With an Established Laboratory Reference Method. Clin Appl Thromb Hemost. 2019 Jan-Dec;25:1076029619890423. doi: 10.1177/1076029619890423.

    PubMed 31773973

Questions about this trial

What is this clinical trial studying?

An observational study of Deep Vein Thrombosis and Atrial Fibrillation, run by LumiraDx UK Limited at 3 sites in United Kingdom.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 7 inclusion and 13 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 11 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 3 sites in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

To determine the clinical performance of the LumiraDx instrument (time frame: 8 weeks). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03682419, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Jun 2026.

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