This question turned up some surprises:
When performing the PTT-based phospholipid neutralization procedure, what limit do you use to confirm lupus anticoagulant?
a. ≥ 8 seconds’ difference between pre- and post-PTT: 8 (33%)
b. Locally computed difference in seconds between pre- and post- PTT: 5 (21%)
c. Ratio ≥ 1.2 between pre- and post-PTT: 4 (17%)
d. Locally computed ratio between pre- and post-PTT: 7 (29%)
Having used mostly integrated Stago Sta-Clot LA kits my whole life, I thought most everyone was using their 8-second difference, but it seems we have a nearly even distribution. Geo.
I am curious: Of those laboratories that are using a locally
I am curious: Of those laboratories that are using a locally computed difference in seconds between pre and post-PTT, what are they using for a % DIFFERENCE cut-off value? Is this value very similar between different laboratories?