B - 107 Is the Flynn Effect Present in a Veteran Outpatient Clinic Sample?

Abstract Objective The Flynn Effect refers to improvement in cognitive scores over time due to advancements in education quality, nutrition, and socioenvironmental variables. Recent studies suggest cognitive scores may plateau or decline over time. Characterization of cohort effects in cognitive performance has implications for normative group selection and identification of brain illness. This study examines cognitive performances of veterans using older and newer versions of normative data to determine if a Flynn effect is present. Method Veterans (N = 189) who passed TOMM and completed the Trail-Making Test (TMT), Animal Naming, and California Verbal Learning Test-II (CVLT-II) were selected for inclusion. The sample was 81% male, racially diverse (49% White/Caucasian, 31% Black/African American, 16% Hispanic/Latino, 4% other), and diagnostically diverse (13% no diagnosis, 33% cognitive disorder, 54% psychiatric diagnosis). Normative scores were calculated from CVLT-II/CVLT-3 manuals for Trial 1, Trial 5, and LDFR; ADC Uniform Data Sets (UDS) were used for TMT-A/B and Animals. Wilcoxon matched-pairs signed rank tests examined differences in z-scores across older and newer normative data. Results Median z-scores were significantly lower using updated UDS norms for TMT-A (z = −11.60, p < 0.001), TMT-B (z = −10.41, p < 0.001), and Animals (z = −11.76, p < 0.001), while CVLT Trial 1 z-scores were significantly higher using CVLT-3 norms (z = 11.24, p < 0.001). CVLT Trial 5 and LDFR medians did not differ. Conclusion Findings demonstrate the need to examine cohort differences in normative reference groups to ensure accurate detection of brain illness. Furthermore, the Flynn Effect may not apply uniformly across domains within a period.