CORE A. PARTICIPANT MEASURES AND ASSESSMENTS SUMMARY/ABSTRACT During the course of the ASPREE study, a vast amount of clinical, physical function, cognitive and quality of life data (~26 million data values) were collected from 19,114 participants by trained staff, resulting in excellent participant retention (82% with full involvement at the end of the study), compliance (74% overall) and data quality (99.6% accuracy). This Core will build on the operational success of ASPREE and provide methodological and operational support for all participant-related study activity by coordinating, directing and managing the physiological and neuropsychological assessments and questionnaires conducted routinely in ASPREE-XT participants in both the U.S. and Australia. The Core services will ensure quality, accuracy and thoroughness of data collection from participants through the implementation of comprehensive Standard Operating Procedures (SOPs) and to ensure adherence to SOPs, staff in both countries will be trained prior to commencement of study activity (see Admin Core). Data provided through the activities of Core A are the clinical nexus for all projects, as Core A will provide clinical endpoint triggers to Core B for follow-up. The longitudinal phenotypic data provided by Core A about ASPREE-XT participants will also be of vital importance for addressing the overall aims of this U19 through completion of Project analyzes. Specifically, the collection of information related to cancer screening, cancer incidence, progression, and outcomes are crucial for Project 1 (Cancer). Collection of cognitive data, depression and dementia endpoints are essential for assessing dementia and mild cognitive impairment outcomes in Project 2 (Dementia). Basic activities of daily living, physical function, exhaustion and physical activity data will be collected for assessment of disability and frailty for Project 3 (Disability). Consequently, the success of the U19 hinges upon the data that will be collected as part of this Core. 0