Choices Reflex to a lupus anticoagulant profile. Reflex to FVIII, FIX, and FXI activity assays. Make a new 1:1 mix, incubate 2 h at 37 C and repeat. Report the presence of a specific inhibitor such as anti-FVIII. CAPTCHAPlease confirm you are a human visitor to prevent automated spam submissions.