B – 38 New Psychometric Criteria for Defining Memory Impairment in Traumatic Encephalopathy Syndrome

Abstract Objective Traumatic encephalopathy syndrome is a later-in-life clinical condition believed to be associated with repetitive low-level neurotrauma experienced during participation in contact, collision, or combat sports—or during military service. Research diagnostic criteria for traumatic encephalopathy syndrome were published in 2021. Memory impairment is included, but validated psychometric criteria for defining this impairment were not provided. We present new psychometric criteria for memory impairment that can be used in research and clinical practice. Method Participants were 1,400 adults from the Wechsler Memory Scale-Fourth Edition standardization sample. Memory tests included Logical Memory, Verbal Paired Associates, and Visual Reproduction. Algorithms for defining impairment, for the six-score battery and for a four-score battery (Logical Memory and Visual Reproduction), were stratified by level of Test of Premorbid Functioning (ToPF) predicted full scale IQ (FSIQ) scores (i.e., ≤79, 80-89, 90-109, 110-119, and ≥120 or greater)—with base rates fixed at or below the 7th percentile. Results For people in the standardization sample with ToPF-predicted FSIQ scores of 110-119, 5.4% of adults and 8.8% of older adults obtain three or more low memory scores on the six-score battery (scaled score≤7). Using the four-score battery, for people with ToPF-predicted FSIQ scores of 90-109, 6.5% obtain two or more low memory scores (scaled score≤5). Conclusion The criteria for memory impairment in traumatic encephalopathy syndrome are defined conceptually as impaired performance on neuropsychological testing at least 1.5 SDs below appropriate norms, accounting for the individual’s estimated premorbid functioning. We provide new, norm-referenced, premorbid functioning stratified algorithms for defining memory impairment.