NEXA: Development and Preliminary Psychometric Properties of a Transdiagnostic Self-Report Measure of Neurodivergent Traits

NEXA (Neurodivergent Expression Assessment) — development and preliminary psychometric properties of a transdiagnostic self-report measure of neurodivergent traits for Brazilian Portuguese-speaking adults. N=1,144 (1,103 complete-case), 85 canonical items, total-scale alpha=.962, general-factor ECV=.429, omega hierarchical=.739, PUC=.890 (empirical, not substantively domain-interpretable; see manuscript). Known-groups d=1.24. NEXA-SF20: same-sample alpha=.914, AUC=.846 (split-sample AUC=.808). Convergent validity: RAADS-R r=.706 (n=161), ASRS-18 r=.430 (n=133), AURA informant r=.43 (n=186). Submitted to the Journal of Personality Assessment. Prospective preregistration of the future confirmatory/definitive validation study: https://doi.org/10.17605/OSF.IO/3SUT7. (c) 2026 NeurAtip. All rights reserved. NEXA items are proprietary; access via Research Use License Agreement.