Thromboembolic Disease RecurrentPREDICTORSNCT02297373
Clinical Predictors for Venous Thromboembolism in Patients With a History of Thrombosis (PREDICTORS)
An observational study of Thromboembolic Disease Recurrent and Deep Vein Thrombosis, run by Ottawa Hospital Research Institute at 9 sites in 3 countries.
Trial summary
Patients with a history of blood clots are at risk of developing additional clots in the future. Doctors use a tool called a clinical decision rule to tell them how likely it is that a patient has a blood clot and if they should have further testing to look for the clot. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Thromboembolic Disease Recurrent, Deep Vein Thrombosis, Pulmonary Embolism
- How many people
- 744 participants
- Where
- 9 sitesin 3 countries
- Study dates
- 19 Nov 2014to 3 Jan 2019
- Phase
- Observational
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: Outpatients presenting with suspected acute recurrent venous thromboembolism (VTE).
Who may be able to join
- Outpatients with clinically suspected acute recurrent DVT or PE regardless of whether the previous event was a DVT or PE
- Age ≥18 years old
- Willing and able to give informed consent
Who cannot join
- Life expectancy less than 3 months
- Suspicion of upper extremity thrombosis or thrombosis at an unusual site (e.g. cerebral or abdominal venous thrombosis)
- Previous VTE was distal DVT or subsegmental PE
- Suspected recurrent VTE is asymptomatic
- Previously enrolled in this study
Trial locations and contacts
9 sites in 3 countries.
9 sites in 3 countries
Canada7 sites
Nova Scotia Health Authority
Halifax, Nova Scotia, B3H 1V7
Hamilton Health Sciences Centre
Hamilton, Ontario, L8L 2X2
Lawson Health Research Institute
London, Ontario, N6G 4A5
Sir Mortimer B. Davis Jewish General Hospital
Montreal, Quebec, H3T 1E2
The Ottawa Hospital
Ottawa, Ontario, K1H 8L6
Hopital Montfort
Ottawa, Ontario, K1K 0T2
Humber River Hospital
Toronto, Ontario, M3M 0B2
About this study
Official title: Clinical Predictors for Venous Thromboembolism in Patients With a History of Thrombosis
Patients with a history of blood clots are at risk of developing additional clots in the future. Doctors use a tool called a clinical decision rule to tell them how likely it is that a patient has a blood clot and if they should have further testing to look for the clot. This tool may cause doctors to over-diagnosis a recurrent clot because the symptoms may be left over from the previous clot. Correctly diagnosing a recurrent blood clot is very important since there are risks associated with both over-diagnosis and under-diagnosis. If a recurrent blood clot is missed (under-diagnosis) the patient is at risk of death from a clot in the lungs. If blood thinners are prescribed when they are not needed (over-diagnosis), the patient may have to take blood thinners for their lifetime and risk having serious bleeding.
Read the detailed description
Several tools have been developed to standardize the diagnostic management of a suspected first blood clot. One of these tools is the use of a clinical decision rule. Clinical decision rules have been designed to help clinicians make diagnostic and therapeutic decisions at the bedside. A score is computed on the presence of some criteria from the patient's medical history, clinical signs and symptoms. The score provides the probability of a blood clot. The rules can be used in combinations with a simple blood test - called D-dimer - to identify patients at low risk who don't require diagnostic imaging testing. Benefits include reduced costs, length in hospital and radiation exposure.
Patients with prior blood clots have been shown to be less likely to benefit from the non-invasive testing. Therefore, they often need to undergo imaging tests, which are frequently difficult to interpret in patients with prior blood clots since residual clots are often present and are difficult to distinguish from a recurrent clot.
The objective of this study is to try to prospectively assess the role of existing clinical decision rules in patients with prior blood clots, and to attempt to improve them in order to increase the yield of non-invasive testing and to reduce the risk of over-diagnosis with imaging tests.
With respect to this study, clots within the deep veins of the legs are called deep vein thrombosis (DVT), while clots in the lungs are called pulmonary embolism (PE).
- Conditions
- Thromboembolic Disease Recurrent, Deep Vein Thrombosis, Pulmonary Embolism, Venous Thromboembolism, Recurrent Thromboembolic Disease
- Medical subject headings
- Venous Thrombosis, Pulmonary Embolism, Venous Thromboembolism, Thromboembolism
What is being measured
The primary outcome is the main question the study is designed to answer.
Validation of the Wells DVT Clinical Decision Rule
The Wells DVT Clinical Decision Rule (CDR) assigns a score from -2 to +9 based on clinical variables (e.g., active cancer, limb swelling, localized tenderness, prior history of DVT, alternative diagnosis as likely or more likely than DVT). In this study, the 3-level Wells DVT CDR was applied prospectively at presentation (Day 0) to participants with suspected recurrent DVT, using data collected from patient history and physical examination. Scores classify patients into low (≤0), moderate (1-2), or high (≥3) probability of DVT. Higher scores indicate greater probability of recurrent DVT. The outcome measure was the rate of confirmed recurrent DVT events within each Wells category, confirmed by objective imaging and adjudicated by an independent committee.
Measured: Day 0 (at time of suspected recurrent DVT)
Validation of the Wells PE Clinical Decision Rule
The 3-level Wells PE score (range 0-12.5) was calculated from history and exam at the index visit. Scores ≤4 = PE unlikely, >4 = PE likely. Higher scores indicate greater likelihood of PE. The outcome is the proportion with confirmed recurrent PE at the index diagnostic work-up, adjudicated by blinded review of imaging.
Measured: Day 0 (at time of suspected recurrent PE)
Validation of the Geneva PE Clinical Decision Rule
The revised Geneva score (range 0-22) was calculated from history and exam at the index visit. Scores 0-3 = low, 4-10 = intermediate, ≥11 = high probability. Higher scores indicate greater likelihood of PE. The outcome is the proportion with confirmed recurrent PE at the index diagnostic work-up, adjudicated by blinded review of imaging.
Measured: Day 0 (at time of suspected recurrent PE)
Secondary outcomes (3)
Accuracy of Current D-dimer Testing Methods
D-dimer testing at the index visit was performed using the institutional cut-off for positivity in place during the study period (2014-2019). Results were classified as positive or negative. The outcome is the proportion with confirmed recurrent VTE in each test category at the index diagnostic work-up, adjudicated by blinded review of imaging.
Measured: Day 0 (at time of suspected recurrent VTE)
Rate of Confirmed Events Using Current Wells DVT/Wells PE/Geneva PE in Participants on Anticoagulant Therapy
The Wells DVT, Wells PE, and Geneva PE scores were calculated at the index visit in participants on anticoagulation. Score ranges and cut-offs as per respective rules. The outcome is the proportion with confirmed recurrent VTE in each risk category at the index diagnostic work-up, adjudicated by blinded review of imaging.
Measured: Day 0 (at time of suspected recurrent VTE)
All-Cause Mortality Within 90 Days of Index Visit
Number of participants who died from any cause from enrollment (Day 0) through Day 90 follow-up for those without confirmed recurrent VTE at enrollment.
Measured: From enrollment (Day 0) through Day 90 follow-up for those not diagnosed with a confirmed recurrent VTE at enrollment
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Nov 2014 (estimated)
- Study start19 Nov 2014
- Primary completion3 Jan 2019
- Study completion3 Jan 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Thromboembolic Disease RecurrentStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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
- Cohort
- Time perspective
- Prospective
- Enrolment
- 744 participants (actual)
Sponsor and investigators
- Lead sponsor
- Ottawa Hospital Research Institute
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Gregoire Le Gal, MD, Principal investigator, Ottawa Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02297373
- Sponsor's protocol ID
- 20140622-01H
- Acronym
- PREDICTORS
- Status last verified
- Sep 2025
- First submitted
- 15 Oct 2014
- Last updated
- 5 Sep 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Mai V, Martens ESL, Righini M, Schulman S, Thiruganasambandamoorthy V, Bates V, Pecarskie A, Kovacs MJ, Visser S, Shivakumar S, Tan M, Rodger M, Scarvelis D, Delluc A, Girard P, Huisman MV, Wells PS, Klok FA, Le Gal G, Kahn SR; PREDICTORS study group. Patterns of presentation of suspected and confirmed recurrent venous thromboembolism in patients with prior venous thromboembolism. Res Pract Thromb Haemost. 2026 Mar 25;10(3):103442. doi: 10.1016/j.rpth.2026.103442. eCollection 2026 Mar.
PubMed 42058833Mai V, Martens ESL, Righini M, Schulman S, Thiruganasambandamoorthy V, Kahn SR, Pecarskie A, Kovacs MJ, Visser S, Shivakumar S, Tan M, Kearon C, Rodger M, Scarvelis D, Delluc A, Girard P, Huisman MV, Wells PS, Klok FA, Le Gal G; PREDICTORS study group. Performance of clinical decision rules in patients presenting with suspected recurrent venous thromboembolism: a multicenter prospective cohort study. J Thromb Haemost. 2025 Oct;23(10):3239-3250. doi: 10.1016/j.jtha.2025.06.019. Epub 2025 Jun 25.
PubMed 40578691