Medicine Best assay for deficiency of von Willebrand factor is- A Bleeding time B APTT C BT + APTT D BT + APTT + vWF-ristocetin factor assay 💡 Explanation Best assay for deficiency of von Willebrand factor is- ✓ Correct Answer: D. BT + APTT + vWF-ristocetin factor assay