One point each awarded for the following:
Platelet count < 30,000/uL
Evidence of hemolysis (retic count > 2.5%, undetectable haptoglobin, or indirect bili > 2.0)
No active cancer
No history of solid-organ or stem-cell transplant
MCV < 90 fl
INR < 1.5
Creatinine < 2.0 mg/dL
A score of 0-4 indicates low risk of severe ADAMTS13 deficiency
Score of 5 is intermediate risk
Score of 6 or 7 indicates high risk
Reference: Lancet Haematol 2017;4:e157-e164