Mixing Study for Evaluation of Abnormal Coagulation Testing

An 84-year-old woman with a history of chronic kidney disease, prior stroke, and hypertension but no personal or family history of bleeding disorders was admitted with a 2-week history of spontaneous subcutaneous ecchymoses and hematomas. She had normal vital signs, laboratory results showing isolated severe anemia but unremarkable for other causes of anemia, and a large soft-tissue hematoma in the left chest wall without evidence of internal hemorrhage. How do you interpret these test results?
Source: JAMA - Category: Journals (General) Source Type: research