Development of Novel Measures for Alzheimer's Disease Prevention Trials

This protocol has the goal of validating novel cognitive and everyday functional measures that have sharply attenuated practice effects and are not prone to ceiling effects for use in preclinical Alzheimer's disease (AD) trials in which participants are cognitively within normal limits. To implement this, we will conduct an innovative parallel group study in which 400 healthy, non-cognitively impaired older subjects are randomized to one of two groups based on assessment type (novel instruments vs. established) and receive three serial assessments over a one year period. Novel cognitive measures include tests of executive function, episodic memory, and processing speed combined into a single composite. Novel functional measures involve computerized performance based, ecologically relevant instrumental activities. We will compare our novel No Practice Effects (NPE) cognitive battery and Miami Computerized Functional Assessment Scale (CFAS) against established measures that include the ADAS-COG in order to determine which battery (novel or established) has better psychometric properties and is less sensitive to practice effects in this clinical trials structure.