aPTT
Single-Factor Assay - 2
Reference curve prepared
Determining % activity :
Patient PPP plasma dilutions mixed
with factor deficient plasma and aPTT performed in duplicate.
Patient clotting time is converted
to % activity using reference curve
Factor VIII =
50 – 150 %
All testing done in duplicate
All must agree within 10% of each
other
Expected
activity range :
Quality
control :