{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T15:34:47Z","timestamp":1789486487267,"version":"build-2803163510"},"reference-count":32,"publisher":"Walter de Gruyter GmbH","issue":"9","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,24]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec id=\"j_cclm-2026-0168_abs_001\">\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Fluid biomarkers are central to the biological definition and diagnosis of Alzheimer\u2019s disease (AD). Despite international recommendations, substantial variability persists in laboratory practices. This survey, promoted by the Committee: Harmonisation (C:H) of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM), aimed to assess real-world laboratory practices for AD biomarker testing.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_cclm-2026-0168_abs_002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>An online survey was distributed to EFLM members. The questionnaire addressed pre-analytical, analytical, and post-analytical practices for cerebrospinal fluid (CSF) and blood-based AD biomarkers. Descriptive statistics were applied.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_cclm-2026-0168_abs_003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 316 responses from more than 35 countries were collected. CSF remained the primary matrix for AD diagnostics, although blood-based biomarkers were increasingly implemented. Marked heterogeneity was observed across all phases of testing, including sample handling, assay platforms, biomarker panels, and decisional cut-offs. Cut-off values for core biomarkers varied widely, as well as harmonization of reporting unit and the adoption of SI units preventing a shared approach to interpreting the results.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_cclm-2026-0168_abs_004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Despite growing clinical adoption, AD biomarker\u00a0testing remains highly heterogeneous. Coordinated international harmonization of pre-analytical procedures, analytical methods, and post-analytical interpretation, particularly for blood-based biomarkers, is urgently required to ensure reliable and comparable results.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1515\/cclm-2026-0168","type":"journal-article","created":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T14:53:50Z","timestamp":1773759230000},"page":"1966-1973","source":"Crossref","is-referenced-by-count":3,"title":["Current practices and harmonization challenges in Alzheimer\u2019s disease biomarkers: an EFLM Committee: Harmonization Survey"],"prefix":"10.1515","volume":"64","author":[{"given":"Luisa","family":"Agnello","sequence":"first","affiliation":[{"name":"Department of Biomedicine, Neurosciences, and Advanced Diagnostics , Institute of Clinical Biochemistry, Clinical Molecular Medicine, and Clinical Laboratory Medicine, University of Palermo , Palermo , Italy"},{"name":"Department of Laboratory Medicine , University Hospital Paolo Giaccone , Palermo , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lora","family":"Dukic","sequence":"additional","affiliation":[{"name":"Clinical Department of Laboratory Diagnostics , Clinical Hospital Center Rijeka , Rijeka , Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leila","family":"Akvlediani","sequence":"additional","affiliation":[{"name":"Faculty of Natural Sciences and Health Care , Batumi Shota Rustaveli State University , Batumi , Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Zaninotto","sequence":"additional","affiliation":[{"name":"QI.LAB.MED, Spin-off of the University of Padova , Padova , Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"374","published-online":{"date-parts":[[2026,3,16]]},"reference":[{"key":"2026091512595721578_j_cclm-2026-0168_ref_001","doi-asserted-by":"crossref","unstructured":"Reuben, DB, Kremen, S, Maust, DT. 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