MOSAAIC Cognitive Assessment Reading Center Administrative Supplement - Project Summary The Multiethnic Observational Study in American Asian and Pacific Islander Communities (MOSAAIC) is a landmark, NHLBI-funded longitudinal cohort study designed to address critical gaps in health research among Asian American, Native Hawaiian, and Pacific Islander (AANHPI) populations. By enrolling 10,000 participants across generations, regions, and languages, MOSAAIC aims to generate comprehensive data on cardiometabolic, mental, and cognitive health. Through clinical examinations, biospecimen collection, and annual follow-ups, the study will provide the most robust and inclusive dataset available to investigate health disparities within these historically underrepresented communities. As part of its in-person examination, MOSAAIC administers a brief but comprehensive cognitive battery to all main cohort participants. The battery assesses multiple cognitive domains—semantic fluency, memory encoding and recall, attention, executive function, processing speed, and visuospatial skills—and has been translated into five AANHPI-relevant languages (Traditional Chinese, Simplified Chinese, Korean, Tagalog, and Vietnamese) using a community-informed, linguistically rigorous process. Given the diversity of study populations and field settings, ensuring standardized administration and scoring is essential to maintaining the reliability and scientific value of the cognitive data. This administrative supplement proposes to establish a centralized Neurocognitive Reading Center within the Coordinating Center to provide infrastructure for high-quality cognitive data collection. The Reading Center will be responsible for developing standardized training materials, certifying CCFC staff, and providing ongoing review of scoring forms and audio recordings to ensure scoring fidelity and inter-rater reliability. It will also support the electronic upload system for cognitive assessments, troubleshoot field-level issues, and lead harmonization of outcome variables across languages and sites. The Reading Center will be equipped to support the validation and oversight of additional cognitive measures as the study evolves. By improving data quality and comparability across diverse participants and settings, this initiative directly enhances the scientific rigor of MOSAAIC’s cognitive outcomes. It supports the parent study’s long-term objectives of advancing research capacity, promoting data equity, and generating actionable insights into brain health and cognitive aging in AANHPI communities. Ultimately, these efforts will strengthen MOSAAIC’s potential to inform culturally responsive public health strategies and reduce disparities in neurological and cognitive health.