
R.E.B.E.L. EM - Salim Rezaie - April 28, 2014
"D-dimer testing is sensitive for thrombus formation, and in patients who are not high risk, this test is used to rule-out venous thromboembolism. D-dimer has been shown to increase with age, which can cause a lower specificity (i.e. more false positive tests) in older patients. Specificity can range from 49 – 67% in patients ≤ 50 years of age, but in older patients (i.e. ≥ 80 years of age) the specificity is quoted as 0 – 18%. The result of this is, older patients often have more diagnostic imaging, but a higher cut-off may lead to increased false negative cases (i.e. missed VTE) and make this strategy less safe. So could age adjusted d-dimer testing increase specificity without affecting sensitivity?"
http://rebelem.com/age-adjusted-d-dimer-testing/