The primary objective of this study is to develop and validate claims-based algorithms to identify intracerebral hemorrhage \>1 cm in diameter, ensuring differentiation from amyloid-related imaging abnormality-microhemorrhage and hemosiderin deposit (ARIA-H; microhemorrhage, superficial siderosis) in participants with Alzheimer's disease (AD) using claims data in the United States (US) with linkage to electronic health records (EHRs), and to estimate the positive predictive values (PPVs) of the algorithms. The secondary objective of the study is to validate claims-based algorithms to identify new-onset seizures in participants with AD using US claims data with linkage to EHRs and to estimate the PPVs of the algorithms.