{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T08:45:54Z","timestamp":1790757954120,"version":"4.1.0"},"reference-count":31,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T00:00:00Z","timestamp":1768521600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005363","name":"Universidad de Buenos Aires","doi-asserted-by":"publisher","award":["20020150100033BA"],"award-info":[{"award-number":["20020150100033BA"]}],"id":[{"id":"10.13039\/501100005363","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003074","name":"Agencia Nacional de Promoci\u00f3n Cient\u00edfica y Tecnol\u00f3gica","doi-asserted-by":"publisher","award":["2019-0930"],"award-info":[{"award-number":["2019-0930"]}],"id":[{"id":"10.13039\/501100003074","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,3,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Increases in obesity and hypertriglyceridemia worldwide, together with lower LDL cholesterol (LDL-c) values from new lipid-lowering agents, prompted the development of new estimation formulas including Martin (M-LDL-c), extended Martin (ME-LDL-c), and Sampson (S-LDL-c) equations. These require validation in different populations.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Lipid profiles with direct LDL-c (D-LDL-c) by homogeneous assay were collected from 22 748 patients in Argentina. Friedewald (F-LDL-c), S-LDL-c, M-LDL-c, and ME-LDL-c were calculated. Patients were classified into treatment categories using both D-LDL-c and each formula independently. Datasets were subdivided by triglycerides (TG). Lipid ratio plot (LRP) provided indirect comparison to beta quantification (BQ). Passing\u2013Bablok, Bland\u2013Altman, and clinical concordance (kappa index) analyses assessed formula performance against D-LDL-c.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>LRP analysis showed S-LDL-c had the closest agreement with BQ surrogate line, followed by D-LDL-c. All formulas showed good correlation with D-LDL-c (r &amp;gt; 0.95) and moderate concordance (kappa &amp;gt; 0.6). M-LDL-c and ME-LDL-c demonstrated the best clinical concordance with D-LDL-c overall. Performance decreased with increasing TG for all formulas. F-LDL-c deteriorated from 200\u2005mg\/dL (2.28\u2005mmol\/L) TG, while S-LDL-c, M-LDL-c, and ME-LDL-c maintained acceptable performance up to 400\u2005mg\/dL (4.56\u2005mmol\/L) TG.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>S-LDL-c, M-LDL-c, and ME-LDL-c showed better agreement with D-LDL-c than F-LDL-c in this South American population. LRP analysis suggests S-LDL-c may provide most accurate estimation vs gold standard BQ, particularly in hypertriglyceridemia. These findings support the adoption of newer equations in clinical practice.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jalm\/jfaf204","type":"journal-article","created":{"date-parts":[[2025,12,13]],"date-time":"2025-12-13T12:55:31Z","timestamp":1765630531000},"page":"241-256","source":"Crossref","is-referenced-by-count":2,"title":["Comparison of the Friedewald, Sampson, and Martin Formulas with Direct Homogeneous Assay of Low-Density Lipoprotein Cholesterol in South American Patients"],"prefix":"10.1093","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-2432-0806","authenticated-orcid":false,"given":"Nahuel","family":"Fernandez Machulsky","sequence":"first","affiliation":[{"name":"Departamento de Bioqu\u00edmica Cl\u00ednica, Bioqu\u00edmica Cl\u00ednica 1, Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]},{"name":"Instituto de Fisiopatolog\u00eda y Bioqu\u00edmica Cl\u00ednica (INFIBIOC), Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dario","family":"Jacobsen","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica Cl\u00ednica, Bioqu\u00edmica Cl\u00ednica 1, Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]},{"name":"Instituto de Fisiopatolog\u00eda y Bioqu\u00edmica Cl\u00ednica (INFIBIOC), Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abi","family":"Cardozo Madaf","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica Cl\u00ednica, Bioqu\u00edmica Cl\u00ednica 1, Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]},{"name":"Instituto de Fisiopatolog\u00eda y Bioqu\u00edmica Cl\u00ednica (INFIBIOC), Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonella","family":"Fochi","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica Cl\u00ednica, Bioqu\u00edmica Cl\u00ednica 1, Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]},{"name":"Instituto de Fisiopatolog\u00eda y Bioqu\u00edmica Cl\u00ednica (INFIBIOC), Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Eugenia","family":"Gomez","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica Cl\u00ednica, Bioqu\u00edmica Cl\u00ednica 1, Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]},{"name":"Instituto de Fisiopatolog\u00eda y Bioqu\u00edmica Cl\u00ednica (INFIBIOC), Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela","family":"Berg","sequence":"additional","affiliation":[{"name":"Departamento de Bioqu\u00edmica Cl\u00ednica, Bioqu\u00edmica Cl\u00ednica 1, Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]},{"name":"Instituto de Fisiopatolog\u00eda y Bioqu\u00edmica Cl\u00ednica (INFIBIOC), Facultad de Farmacia y Bioqu\u00edmica, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]},{"name":"CONICET, Universidad de Buenos Aires , Buenos Aires ,","place":["Argentina"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,1,16]]},"reference":[{"key":"2026030508522259500_jfaf204-B1","author":"World Health Organization"},{"key":"2026030508522259500_jfaf204-B2","doi-asserted-by":"crossref","first-page":"2459","DOI":"10.1093\/eurheartj\/ehx144","article-title":"Low-density lipoproteins cause atherosclerotic cardiovascular disease. 1. 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