Major risk factors for VTE are common in symptomatic outpatients, suggesting a potential need to test extended DVT prophylaxis in this setting.
Major risk factors for venous thromboembolism are a common cause of DVT among symptomatic outpatients; therefore, the usefulness of extending DVT prophylaxis in the outpatient setting should be tested. The role of additional risk factors in the development of DVT needs to be established by properly designed studies.
Alberto Cogo (1994) studied this question.