P4‐350: A COMPARISON OF MULTI‐TEST OPERATIONALIZATIONS OF COGNITIVE DECLINE USING LONGITUDINAL NORMS: ASSOCIATIONS WITH PROGRESSION TO COGNITIVE IMPAIRMENT AND AMYLOID STATUS

Preclinical cognitive impairment is typically identified by comparing patient performance to cross-sectional norms such that multiple scores below a specified threshold are deemed abnormal. Such methods do not detect AD-related decline in persons who start high and remain “normal” relative to cross-sectional thresholds despite worsening performance. Longitudinal norms may be sensitive to this type of early decline or underlying AD pathology. The...