O2‐03‐04: DEFINING AMYLOID PET POSITIVITY: WHAT IF THE COIN HAD MORE THAN TWO SIDES?. (1st July 2019) - McRae-McKee, Kevin; de Jager, Celeste A.; Bajaj, Sumali; Udeh-Momoh, Chinedu T.; Hadjichrysanthou, Christoforos; Ahmadi-Abhari, Sara; Bracoud, Luc; McNaughton, Emily; Scott, David; de Wolf, Frank; Anderson, Roy M.; Middleton, Lefkos T.