Problem: A 26-year-old female presents for a routine annual examination. She reports a history of heavy menstrual bleeding since menarche and states her mother had similar symptoms. She reports episodes of epistaxis a few times each month and states she bruises easily. Physical examination is unremarkable. Labs include: Hgb 7.9 g/dL Hct 23.9% MCV 69 fL Platelet count 230,000/ microliter PT 12 seconds (normal) PTT 30 seconds (normal) What is the most appropriate next test to order? Factor IX level Ristocetin cofactor activity Mixing study D-dimer. Need Assignment Help?