Inclusion Criteria:  Be ≥18 years of age at the time of anticoagulation initiation. Have active cancer admitted to the hospital, emergency department or observation unit for acute DVT and/or PE. Treated with rivaroxaban (or any DOAC in secondary analysis) or LMWH as their first anticoagulant on day 7 post-acute CAT event diagnosis (index date) o increase the probability of accurately classifying patients' intended outpatient anticoagulant for CAT treatment and that patients are compared at the same point from diagnosis. Have been active in the data set for at least 12-months prior to the index event (based on the "First Month Active" field) and had at least one provider visit in the 12-months prior to the acute VTE event (baseline period).  Exclusion Criteria:  Evidence of atrial fibrillation, recent hip/knee replacement (within 35 days of index VTE), ongoing VTE treatment, valvular heart disease defined as any rheumatic heart disease, mitral stenosis, or mitral valve repair/replacement. Pregnancy. Initiation of rivaroxaban at a dose other than 15 mg twice daily or non-therapeutic doses of other DOAC or LMWH (e.g., enoxaparin at a dose other than 1 mg/kg twice daily or 1.5 mg/kg once daily; dalteparin at a dose other than 200 IU/kg of total body weight) Evidence of use of anticoagulation use during the 12-months prior per written prescription or patient self-report