Inclusion Criteria:

- age 18 and older

- at least one record of a primary inpatient discharge diagnosis of cancer (index
hospitalization)

- a procedure code for a cancer-related surgery during the index hospitalization

- a code for an anticoagulant treatment (dalteparin, enoxaparin, fondaparinux or
unfractionated heparin (UFH)) as thromboprophylaxis therapy during the day prior to
or two days after cancer-related surgery during the index hospitalization (this is
the INDEX EVENT)

Exclusion Criteria:

- a record that the patient received more than one injectable anticoagulant on Day 1 of
anticoagulant therapy

- a record that the patient received anticoagulant therapy prior to index anticoagulant

- a primary diagnosis code of DVT, PE, or major bleed

- evidence of an outpatient emergency department or hospital outpatient clinic visit
that included a diagnosis code for DVT or PE during the 6 months prior to the index
hospitalization

- patient records for patients transferred from another facility outside Premier system
on index hospitalization