{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T17:36:45Z","timestamp":1790617005413,"version":"4.1.0"},"reference-count":53,"publisher":"Public Library of Science (PLoS)","issue":"10","license":[{"start":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T00:00:00Z","timestamp":1759449600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Anaemia is highly prevalent and commonly caused by nutritional deficiencies. Guidelines often include an algorithm to find the underlying cause. Here, we compared diagnostic algorithms and suggested laboratory tests for anaemia in clinical practice guidelines in countries with similar healthcare systems, focusing on iron, vitamin B12 and folate deficiency in the general adult population.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We searched for diagnostic guidelines on anaemia in the Trip, Guidelines International Network and country specific databases. To be selected, the guidelines had to include diagnostic criteria or algorithms to determine the cause of anaemia in the general adult population.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In total, 14 records were included. For iron deficiency anaemia, guidelines varied in diagnostic criteria ranging from use of ferritin only, to ferritin in various combinations with a variety of other parameters, with different cut-off values. For vitamin B12 or folate deficiency, besides measurement of vitamin B12 or folate, some guidelines mentioned methylmalonic acid or homocysteine. Quality of evidence underlying cut-offs and parameters was variable, and laboratory aspects were underrepresented.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>There was a lot of variation in the included diagnostic algorithms, especially for iron deficiency anaemia. Differences in cut-off values were seen, even when using similar diagnostic strategies. Furthermore, supporting evidence was variable. Further research is needed to determine optimal algorithms. Our findings highlight the need for inclusion of relevant laboratory aspects in guidelines, appropriate diagnostics and clinical decision limits.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0333688","type":"journal-article","created":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T17:29:21Z","timestamp":1759512561000},"page":"e0333688","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":2,"title":["Comparison of diagnostic algorithms used in guidelines on nutritional anaemias in adults"],"prefix":"10.1371","volume":"20","author":[{"given":"Margaretha G. M.","family":"Roemer","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wendy P. J.","family":"den Elzen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosalinde K. E.","family":"Poortvliet","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacobijn","family":"Gussekloo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Steef","family":"Kurstjens","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bauke A.","family":"de Boer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9638-9115","authenticated-orcid":true,"given":"Anne Margreet","family":"de Jong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,10,3]]},"reference":[{"key":"pone.0333688.ref001","volume-title":"Worldwide prevalence of anaemia 1993-2005 - WHO global database on anaemia","author":"World Health Organization","year":"2008"},{"issue":"1","key":"pone.0333688.ref002","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1186\/s13045-021-01202-2","article-title":"Burden of anemia and its underlying causes in 204 countries and territories, 1990-2019: results from the Global Burden of Disease Study 2019","volume":"14","author":"S Safiri","year":"2021","journal-title":"J Hematol Oncol"},{"issue":"2","key":"pone.0333688.ref003","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1016\/j.mcna.2016.09.003","article-title":"Anemia: Evaluation and Diagnostic Tests","volume":"101","author":"MJ Cascio","year":"2017","journal-title":"Med Clin North Am"},{"issue":"2","key":"pone.0333688.ref004","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/j.hoc.2015.11.002","article-title":"The Global Burden of Anemia","volume":"30","author":"NJ Kassebaum","year":"2016","journal-title":"Hematol Oncol Clin North Am"},{"key":"pone.0333688.ref005","article-title":"The cause of anemia is underdiagnosed in primary care","volume":"167","author":"A-M de Jong","year":"2023","journal-title":"Ned Tijdschr Geneeskd"},{"issue":"11","key":"pone.0333688.ref006","article-title":"The landscape of inappropriate laboratory testing: a 15-year meta-analysis","volume":"8","author":"M Zhi","year":"2013","journal-title":"PLoS One"},{"issue":"1","key":"pone.0333688.ref007","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1186\/s12911-020-01198-8","article-title":"Preventing overuse of laboratory diagnostics: a case study into diagnosing anaemia in Dutch general practice","volume":"20","author":"MMA Kip","year":"2020","journal-title":"BMC Med Inform Decis Mak"},{"key":"pone.0333688.ref008","unstructured":"Centre for Perioperative Care. 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