The Designer D-dimer Deep Vein Thrombosis Diagnosis (4D) Study (4D)

September 27, 2021 updated by: McMaster University

D-dimer Testing, Tailored to Clinical Pretest Probability, to Minimize Initial and Follow-up Ultrasound Imaging in Suspected Deep Vein Thrombosis: A Management Study

This is a cohort study that will assess a new diagnostic management strategy for suspected Deep Vein Thrombosis in outpatients.The new diagnostic strategy is designed to reduce the use of ultrasound testing on the day of presentation, and reduce repeat ultrasound testing a week after an initial normal test.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Detailed Description

This is a prospective, multicentre, cohort study that will assess a new diagnostic management strategy for suspected Deep Vein Thrombosis in outpatients. The new diagnostic strategy is designed to reduce the use of ultrasound testing on the day of presentation, and reduce repeat ultrasound testing a week after an initial normal test. Less ultrasound testing will be performed because: i) more patients will have deep vein thrombosis excluded by combinations of Clinical Pretest Probability and D-dimer results on the day of presentation; and, ii) in those who still need an ultrasound, a repeat ultrasound a week after a normal result will only be performed if the D-dimer result is markedly abnormal at initial presentation. The safety of this management strategy will be established by demonstrating a very low rate of proximal Deep Vein Thrombosis or Pulmonary Embolism during 90 days follow-up in patients who had anticoagulant therapy withheld in response to negative diagnostic testing. Diagnostic test utilization will be assessed. All clinical outcomes will be adjudicated by a central independent adjudication committee that will be blind to initial D-dimer measurements and patient management.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
1513

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Canada
    • Alberta
      • Edmonton, Alberta, Canada, T6G 2B7
        • University of Alberta Hospital
    • Nova Scotia
      • Halifax, Nova Scotia, Canada, B3H1V7
        • Nova Scotia Cancer Centre
    • Ontario
      • Hamilton, Ontario, Canada, L8N 4A6
        • St. Joseph's Healthcare
      • Hamilton, Ontario, Canada, L8L 2X2
        • Hamilton Health Sciences - Hamilton General
      • Hamilton, Ontario, Canada, L8N 3Z5
        • Hamilton Health Sciences - McMaster
      • Hamilton, Ontario, Canada, L8V1C3
        • Juravinski Cancer Hospital
      • London, Ontario, Canada, N6A 5W9
        • London Health Sciences Centre
      • Ottawa, Ontario, Canada, K1H 8L6
        • The Ottawa Hospital Regional Centre
    • Quebec
      • Montreal, Quebec, Canada, H3T 1E2
        • The Jewish General Hospital
      • Sherbrooke, Quebec, Canada, J1G2EB
        • Centre Hospitalier Universitaire de Sherbrooke

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (ADULT, OLDER_ADULT)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Probability Sample

Study Population

Male and females outpatients with a suspected Deep Vein Thrombosis

Description

Inclusion Criteria:

1) Consecutive outpatients (i.e. non-hospitalized patients) with clinically suspected Deep Vein Thrombosis.

Exclusion Criteria:

  1. Age less than 18 years.
  2. Treated with full-dose anticoagulation for ≥ 24 hours before D-dimer was measured.
  3. D-dimer level known before Clinical Pretest Probability documented.
  4. Ultrasound of the leg performed before Clinical Pretest Probability was documented
  5. Ultrasound was or will be performed in a patient with low Clinical Pretest Probability and a d-dimer <1000(or equivalent), or with Moderate Clinical Pretest Probability and a D-dimer <500 (or equivalent) (e.g. suspected bleeding).
  6. Ongoing need for anticoagulant therapy.
  7. Suspected Pulmonary Embolism.
  8. Superficial venous thrombosis that requires, or may require, anticoagulant therapy.
  9. Life expectancy less than 3 months.
  10. Previously confirmed episode of Deep Vein Thrombosis.
  11. Geographic inaccessibility which precludes follow-up.
  12. Known pregnancy.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
No Ultrasound
Low Clinical Pretest Probability and D-dimer < 1000 ug/L; Moderate Clinical Pretest Probability and D-dimer < 500 ug/L
Ultrasound Required
Low Clinical Pretest Probability and D-dimer 1000 - 3000 ug/L; Moderate Clinical Pretest Probability and D-dimer 500 - 3000 ug/L; High Clinical Pretest Probability

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Confirmed symptomatic proximal Deep Vein Thrombosis
Time Frame: within 90 days
The primary outcome is confirmed symptomatic proximal Deep Vein Thrombosis (including involvement of the calf vein trifurcation but not isolated more distal Deep Vein Thrombosis; or pulmonary embolism (not including isolated sub-segmental abnormalities on Computed Tomography Pulmonary Angiogram; within 90 days (± 7 days for follow-up assessment) that is not diagnosed by scheduled diagnostic testing (includes events that occur between initial and scheduled follow-up proximal ultrasound examinations).
within 90 days

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Clinical Pretest Probability/ D-dimer/ Compression Ultrasound subgroups
Time Frame: within 90 days

The primary outcome in the following subgroups:

  • Low Clinical Pretest Probability and D-dimer <1000 ug/L
  • Moderate Clinical Pretest Probability and D-dimer <500 ug/L
  • Moderate Clinical Pretest Probability and D-dimer 500 -999 ug/L
  • High Clinical Pretest Probability and D-dimer <500 ug/L
  • Low Clinical Pretest Probability and D-dimer 1000-2999 ug/L and negative initial ultrasound
  • Moderate Clinical Pretest Probability and D-dimer 1000-2999 ug/L and negative initial ultrasound
  • High Clinical Pretest Probability and D-dimer 500-1499 ug/L and negative initial ultrasound
within 90 days
Death
Time Frame: within 90 days
Death within 90 days (± 7 days for follow-up assessment).
within 90 days

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
McMaster University

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Canadian Institutes of Health Research (CIHR)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Study Director: Mark Levine, MD, ocog

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
February 1, 2014

Primary Completion (ACTUAL)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 17, 2020

Study Completion (ACTUAL)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
October 15, 2020

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
January 13, 2014

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 14, 2014

First Posted (ESTIMATE)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 16, 2014

Study Record Updates

Last Update Posted (ACTUAL)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 28, 2021

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 27, 2021

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2021

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • OCOG-2013-4D

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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