Venous thromboembolism, which most commonly manifests as deep venous thrombosis (DVT) of the extremities and pulmonary embolism, affects more than 500 000 Americans annually and is the third most common cause of cardiovascular mortality in the United States. Upper-extremity DVT (UE-DVT) accounts for about 10% of all DVT cases, yet there have been few studies, to our knowledge, that provide high-level evidence of the best diagnostic strategy to confirm or refute this disorder.