{"doi":"10.1002/alz.70200","title":"Evaluating linked ICD‐10 Medicare claims data as a method of dementia case ascertainment in research settings","abstract":"INTRODUCTION: US Medicare claims can be used to identify dementia cases for research. Our objective was to evaluate the performance of International Classification of Diseases, 10th Revision (ICD-10) code definitions versus research-based dementia ascertainment. METHODS: Participants of five Rush Alzheimer's Disease Center (RADC) cohorts with study visits between October 2015 and December 2019 and fee-for-service Medicare contributed observations. For each observation, we compared research-based dementia status to dementia status based on six ICD-10 code definitions. RESULTS: A total of 1869 participants contributed 5309 observations (mean age 82.9 years, 21.0% Black, 9.3% met research-based dementia criteria). The accuracy of ICD-10 code definitions was high (87%-90%); five of six code definitions favored specificity over sensitivity. All ICD-10 code definitions were less accurate among subgroups defined by older age, minoritized race, increased depressive symptoms, and history of stroke. DISCUSSION: Performance of ICD-10 code definitions mirrored that of ICD-9 code definitions. Awareness of differential performance by participant characteristics can improve the robustness of research. HIGHLIGHTS: We report the performance of the International Classification of Diseases, 10th Revision (ICD-10) code versus research-based dementia ascertainment. ICD-10 performed worse with age, depressive symptoms, minoritized race, and stroke. Awareness of accuracy and differential performance can improve research robustness.","journal":"Alzheimer s & Dementia","year":2025,"id":510817,"datarank":0.44166584687496613,"base_score":2.9444389791664403,"endowment":2.9444389791664403,"self_citation_contribution":0.44166584687496613,"citation_network_contribution":0.0,"self_endowment_contribution":0.44166584687496613,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":18,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.5597,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":325844,"name":"Lisa L. Barnes","orcid":"0000-0002-0072-9817","position":1,"is_corresponding":false},{"id":417828,"name":"Yi Chen","orcid":"0009-0005-1045-0501","position":2,"is_corresponding":false},{"id":415973,"name":"Kan Z. Gianattasio","orcid":"0000-0002-8665-2856","position":3,"is_corresponding":false},{"id":340012,"name":"Francine Grodstein","orcid":"0000-0002-2699-7051","position":4,"is_corresponding":false},{"id":321317,"name":"Bryan D. James","orcid":"0000-0003-1932-151X","position":5,"is_corresponding":false},{"id":225308,"name":"David X. Márquez","orcid":"0000-0001-8903-4941","position":6,"is_corresponding":false},{"id":957080,"name":"Ali Moghtaderi","orcid":"0000-0002-1728-6434","position":7,"is_corresponding":false},{"id":957079,"name":"Christina Prather","orcid":"0000-0002-9636-8701","position":8,"is_corresponding":false},{"id":42842,"name":"David B. Rein","orcid":"0000-0002-1271-5789","position":9,"is_corresponding":false},{"id":284810,"name":"Raj C. Shah","orcid":"0000-0001-9706-9730","position":10,"is_corresponding":false},{"id":242714,"name":"Emma K. Stapp","orcid":"0000-0003-0628-0704","position":11,"is_corresponding":false},{"id":275267,"name":"Melinda C. Power","orcid":"0000-0001-9099-7964","position":12,"is_corresponding":false},{"id":1215170,"name":"Joya Bhattacharyya","orcid":null,"position":0,"is_corresponding":true}],"reference_count":23,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T02:47:50.575618Z","pmid":"40356037","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}