| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Summaries for Patients are a service provided by Annals to help patients better understand the complicated and often mystifying language of modern medicine.
Doctors use several strategies to diagnose DVT, including blood tests (d-dimer tests) that help measure whether a clot has formed and is breaking down, a scan that looks at blood flow in the veins (ultrasonography), and an x-ray taken after injecting dye into a vein (venography). To decide when to do any of the tests, doctors usually assess a patient's medical background, symptoms, and physical examination. We do not always know, however, which clinical findings are most useful for deciding when to do the tests.
SUMMARIES FOR PATIENTS
Clinical Diagnosis of Deep Venous Thrombosis
19 July 2005 | Volume 143 Issue 2 | Page I-40
Summaries for Patients are presented for informational purposes only. These summaries are not a substitute for advice from your own medical provider. If you have questions about this material, or need medical advice about your own health or situation, please contact your physician. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the American College of Physicians.
The summary below is from the full report titled "Meta-Analysis: The Value of Clinical Assessment in the Diagnosis of Deep Venous Thrombosis." It is in the 19 July 2005 issue of Annals of Internal Medicine (volume 143, pages 129-139). The authors are S. Goodacre, A.J. Sutton, and F.C. Sampson.
What is the problem and what is known about it so far?
![]()
Deep venous thrombosis (DVT) occurs when blood clots form in the large veins of the legs. Pieces of the clots can break off and travel through the bloodstream to the lungs. The clots can cause serious symptoms and even death if they are not diagnosed and treated quickly. Because people with DVT are treated with blood-thinning medicines that can cause serious bleeding, accurate diagnosis is very important.
Why did the researchers do this particular study?
![]()
To see which clinical findings are most useful to assess in patients with possible DVT.
What was studied?
![]()
51 studies that assessed the ability of clinical findings to sort participants into groups with different likelihoods of DVT; the studies involved 54 groups of patients.
How was the study done?
![]()
The authors searched the medical literature up to January 2005 and selected studies that recorded physicians' judgments or clinical findings before patients had diagnostic tests for DVT. In some instances, the physicians used a score, called the Wells rule, to sum the presence or absence of multiple clinical findings. The authors then combined the studies to see how well the clinical findings helped sort patients into groups with different probabilities of DVT.
What did the researchers find?
![]()
Several findings increased the probability of DVT, including a history of DVT, malignant disease, recent immobilization, a difference in calf diameter, and recent surgery. The absence of calf swelling and having no difference in calf diameter decreased the probability of DVT. Scoring the presence and absence of 9 items with the Wells rule correctly sorted the probability of DVT much better than did individual findings, particularly in younger patients and in patients without previous DVT.
What were the limitations of the study?
![]()
The authors found that the study samples, types and numbers of physicians, follow-up methods, tests to diagnose DVT, and findings varied among studies. It was difficult for the authors to summarize and explain all of the findings because the studies varied in many different aspects.
What are the implications of the study?
![]()
Scoring the presence and absence of multiple clinical findings, such as history of DVT, malignant disease, calf swelling, and recent surgery or immobilization, better estimates the probability of DVT than does relying on individual findings.
Related articles in Annals:
This article has been cited by other articles:
![]() |
A. J. Sutton, N. J. Cooper, S. Goodacre, and M. Stevenson Integration of Meta-analysis and Economic Decision Modeling for Evaluating Diagnostic Tests Med Decis Making, September 1, 2008; 28(5): 650 - 667. [Abstract] [PDF] |
||||
![]() |
A. Qaseem, V. Snow, P. Barry, E. R. Hornbake, J. E. Rodnick, T. Tobolic, B. Ireland, J. B. Segal, E. B. Bass, K. B. Weiss, et al. Current Diagnosis of Venous Thromboembolism in Primary Care: A Clinical Practice Guideline from the American Academy of Family Physicians and the American College of Physicians Ann Intern Med, March 20, 2007; 146(6): 454 - 458. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Qaseem, V. Snow, P. Barry, E. R. Hornbake, J. E. Rodnick, T. Tobolic, B. Ireland, J. Segal, E. Bass, K. B. Weiss, et al. Current Diagnosis of Venous Thromboembolism in Primary Care: A Clinical Practice Guideline from the American Academy of Family Physicians and the American College of Physicians Ann. Fam. Med, January 1, 2007; 5(1): 57 - 62. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Goodacre, M. Stevenson, A. Wailoo, F. Sampson, A.J. Sutton, and S. Thomas How should we diagnose suspected deep-vein thrombosis? QJM, June 1, 2006; 99(6): 377 - 388. [Abstract] [Full Text] [PDF] |
||||
![]() |
U. Sachdev, V. J. Teodorescu, M. Shao, T. Russo, T. S. Jacobs, D. Silverberg, A. Carroccio, S. H. Ellozy, and M. L. Marin Incidence and Distribution of Lower Extremity Deep Vein Thrombosis in Rehabilitation Patients: Implications for Screening Vascular and Endovascular Surgery, May 1, 2006; 40(3): 205 - 211. [Abstract] [PDF] |
||||
![]() |
S. M Stevens and W. Ageno Review: the Wells rule is more useful than individual clinical features for predicting risk of deep venous thrombosis Evid. Based Med., April 1, 2006; 11(2): 56 - 56. [Full Text] [PDF] |
||||
![]() |
P. S. Wells, C. Owen, S. Doucette, D. Fergusson, and H. Tran Does This Patient Have Deep Vein Thrombosis? JAMA, January 11, 2006; 295(2): 199 - 207. [Abstract] [Full Text] [PDF] |
||||
![]() |
Ruling Out DVT Journal Watch Cardiology, September 9, 2005; 2005(909): 7 - 7. [Full Text] |
||||
![]() |
Validation of the Wells Score for Predicting DVT Journal Watch Emergency Medicine, August 23, 2005; 2005(823): 4 - 4. [Full Text] |
||||
![]() |
Ruling Out DVT Journal Watch (General), August 12, 2005; 2005(812): 5 - 5. [Full Text] |
||||
![]() |
J. D. Douketis Use of a Clinical Prediction Score in Patients with Suspected Deep Venous Thrombosis: Two Steps Forward, One Step Back? Ann Intern Med, July 19, 2005; 143(2): 140 - 142. [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||