Table 4.

Sample size for a 2-year trial by tracers (using RSF-PVC-based amyloid burden measurements)

Tracer	Reduction in the annual rate of change
	20% less	40% less	60% less	80% less
AV45	2156	539	240	135
PiB	305	77	34	20

Abbreviations: AV45, florbetapir; PiB, Pittsburgh compound B; PVC, partial volume correction; RSF, regional spread function.