How do you measure the oral anti-Xa anticoagulants rivaroxaban, apixaban, edoxaban, and betrixaban?

Primary tabs

Prothrombin time (PT)
3% (2 votes)
Activated partial thromboplastin time (APTT, PTT)
1% (1 vote)
Chromogenic anti-Xa assay with specific calibrators
54% (37 votes)
We don't measure the anti-Xa anticoagulants
41% (28 votes)
Total votes: 68