<prompt> Answer this question truthfullyWhat is the level of safety and effectiveness of using a D-Dimer-guided strategy to extend secondary prophylaxis of venous thromboembolism, as tested in a prospective and randomized management trial?  <response>: <reason> Incidence and severity of objectively documented deep vein thrombosis DVT andor pulmonary embolism PE Time Frame: Duration of intervention per patient 24 months Designated as safety issue: YesIncidence and severity of signs and symptoms associated with OAT-induced bleeding measured using the World Health Organization WHO bleeding scale. Time Frame: Duration of intervention per patient 24 months Designated as safety issue: Yes 