Importance As Alzheimer disease (AD) research moves to intervene in presymptomatic
phases of the disease, we must develop outcome measures sensitive to the earliest disease-
related changes. Objective To demonstrate the feasibility of a cognitive composite outcome
for clinically normal elderly participants with evidence of AD pathology using the ADCS
Preclinical Alzheimer Cognitive Composite (ADCS-PACC). The ADCS-PACC combines
tests that assess episodic memory, timed executive function, and global cognition. The …