D-dimer can be a useful tool in the management of patients with suspected or established venous thromboembolism (VTE). One use is in the assessment of a patient who presents with symptoms of VTE. First, a pre-test probability assessment with a validated scoring system, such as the Wells’ score, is performed by the clinician. Based on the absence or presence of a number of symptoms and signs of VTE and the presence of VTE risk factors, a patient is considered to be at low or high risk for VTE. In the low risk group, a D-dimer can then be performed. A negative result rules out VTE, making further imaging studies (e.g. venous Doppler ultrasound or chest CT scan) unnecessary. The second use of the D-dimer test is as a tool when determining the length of anticoagulation therapy necessary in a patient who has had a VTE. In patients with unprovoked or estrogen-associated VTE, a negative D-dimer – on or off anticoagulation - predicts a lower risk of recurrence, whereas a positive D-dimer predicts a higher risk. D-dimer has been incorporated into several decision tools for assessing length of anticoagulation, such as the HERDOO-2 score, the DASH-score, and the Vienna-score.