{"id":"rdw-cv","name":"Red Cell Distribution Width (RDW-CV)","shortName":"RDW","aliases":["RDW-CV","RDW","Red Cell Distribution Width","Red Cell Dist Width","Erythrocyte Distribution Width","RDW (%)","ADE","Amplitud de distribución eritrocitaria","Red Blood Cell Distribution Width","RDW CV","RDW-CV (%)","Red Cell Distribution Width (RDW-CV)","Red Cell Distribution Width-CV","RDW (CV)"],"abbreviations":["RDW-CV","RDW","RDW CV"],"loinc":[{"code":"788-0","primary":true},{"code":"30385-9","primary":false}],"specimen":"whole-blood","units":[{"ucum":"%","display":"%"}],"referenceRanges":[{"population":"Adults","low":11.7,"high":15.4,"unit":"%","unitDisplay":"%","note":"Labcorp prints 11.7–15.4 on its adult sample reports (women aged 46 and 60) and 11.6–15.4 on a sample report for a 15-year-old male. The American Board of Pathology lists 11.6–14.8 and Health NZ Waikato 12.0–15.0. Limits depend on the analyzer. RDW-SD, reported in fL, is a separate result with different ranges. Large population studies link higher RDW, even inside the usual range, to higher long-term mortality (Perlstein 2009, Patel 2010).","sources":[{"title":"CBC, Platelet, No Differential (test 028142), sample report","url":"https://files.labcorp.com/testmenu-d8/sample_reports/028142.pdf","publisher":"Labcorp","year":2020},{"title":"CBC With Differential/Platelet (test 005009), sample report","url":"https://files.labcorp.com/testmenu-d8/sample_reports/005009.pdf","publisher":"Labcorp","year":2024},{"title":"Hematopathology reference ranges","url":"https://abpath.org/hematopathology-reference-ranges","publisher":"American Board of Pathology"},{"title":"CBC reference intervals (HEM-2597.01)","url":"https://lab.waikatodhb.health.nz/assets/test-attachments/230/CBC-reference-intervals.pdf","publisher":"Te Whatu Ora Health New Zealand, Waikato","year":2024},{"title":"Red blood cell distribution width and mortality risk in a community-based prospective cohort","url":"https://pubmed.ncbi.nlm.nih.gov/19307522/","publisher":"Archives of Internal Medicine","year":2009},{"title":"Red cell distribution width and mortality in older adults: a meta-analysis","url":"https://pubmed.ncbi.nlm.nih.gov/19880817/","publisher":"The Journals of Gerontology: Series A","year":2010}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"How much your red blood cells vary in size. A higher number means a wider mix of small and large cells.","url":"https://bloodtesttracker.com/markers/rdw-cv","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}