The PFA (platelet function analysis) test is prescribed for the exploration of primary hemostasis and the study of platelet-willebrand factor interaction. It is performed using citrated blood, with technical difficulties and frequent alarms that may be linked to the choice of anticoagulant (citrate). It is proposed to compare the results obtained with a conventional citrate tube and a BAPA tube, which is an anticoagulant used in clinical research and which blocks coagulation by another mechanism that would have less impact on blood platelets.

Inclusion Criteria:

• Person having given their non-opposition
• Person of legal age
• Person receiving a haemostasis consultation at the haemophilia and haemorrhagic diseases treatment center followed by a blood sample with a PFA test prescribed by the doctor (the test is not added for the study).

Exclusion Criteria:

• persons under legal protection (curatorship, guardianship)
• persons subject to a court protection order
• pregnant, parturient or breast-feeding women
• adult incapable or unable to give consent
• minor

Patients requiring a PFA test