Appendix A.

PEPPER and Approach Cohort Enrollment Criteria.

Inclusion Criteria

Age 21 or older. Undergoing elective primary hip arthroplasty. Mental capacity to participate and able to comply with study protocols. Able to be randomized to at least 2 of the 3 study prophylaxis regimens. Negative pregnancy test on day of surgery or other criteria (ie, sex or reproductive potential) to ensure patient is not pregnant. Informed consent. Willing to be randomized and to participate. Surgeon confirmed eligibility.

Exclusion Criteria

Revision or second-stage reimplantation total hip surgery, or hip resurfacing arthroplasty. Bilateral hip replacement. Previously enrolled in PEPPER. Pregnant or breastfeeding. Chronic (>6 mo) anticoagulation other than with antiplatelet medications. Currently enrolled in another active interventional clinical trial testing a drug or intervention known or believed to interact with aspirin, warfarin, or rivaroxaban. Documented gastrointestinal, cerebral, or other hemorrhage within 3 months of surgery. Known history of defective hemostasis and clinical bleeding requiring transfusion and treatment. Undergone operative procedure involving eye, ear, or central nervous system within 1 month of the surgery. Severe uncontrolled hypertension with systolic blood pressure greater than 220 mmHg or diastolic blood pressure greater than 120 mmHg. Weight less than 41 kg (90.4 pounds). Vulnerable patient population, including prisoners and institutionalized individuals.

PEPPER, Comparative Effectiveness of Pulmonary Embolism Prevention After Hip and Knee Replacement.