The following is a copy of an article from Evidence-Based Practice, 2007; 10(12):1-2.

Venous thromboembolism refers to a spectrum of disease that includes both pulmonary embolus and deep-venous thrombosis (DVT). More than 250,000 people in the United States are diagnosed annually with venous thromboembolic disease; an estimated equal number of cases goes undiagnosed [1].

Clinicians and official guidelines take a variety of diagnostic approaches toward patients with a suspected DVT. Historically, clinicians have used compression ultrasound and impedance plethysmographyin the outpatient setting to diagnose clinically suspected DVT. More recently, the D-dimer assay has expanded diagnostic options. Nevertheless, D-dimer interpretation can be limited by the test’s low specificity and the necessity of knowing the pretest probability of disease to properly use the results.