{"id":"pdw","name":"Platelet Distribution Width (PDW)","shortName":"PDW","aliases":["PDW","Platelet Distribution Width","Platelet Dist Width","PDW (fL)","PDW-SD","Platelet Distribution Width (PDW)","PDW SD","Platelet Dist. Width"],"abbreviations":["PDW","PDW-SD"],"loinc":[{"code":"32207-3","primary":true},{"code":"51631-0","primary":false}],"specimen":"whole-blood","units":[{"ucum":"fL","display":"fL"},{"ucum":"um3","display":"µm³"}],"referenceRanges":[{"population":"18+","low":9.5,"high":17.2,"unit":"fL","unitDisplay":"fL","note":"From 30,917 healthy Danish blood donors on a Sysmex XN-10 (2.5th to 97.5th percentile), stable across age and sex. This is one analyzer's range, not a universal one: a study of 1,634 Indian donors on a Sysmex XP-100i found 9.1 to 22.5 fL, and other published studies range from 8.2 to 25 fL. Use the range printed on your own report first. The standard CBC reports of Labcorp, ARUP, Quest and Mayo Clinic Laboratories do not list PDW. Results some analyzers report in percent are a different scale and cannot be compared with this range.","sources":[{"title":"Reference intervals for platelet large cell ratio, platelet distribution width, plateletcrit and standard haematological parameters determined on the Sysmex XN-10 in a cohort of 30,917 Danish blood donors","url":"https://pubmed.ncbi.nlm.nih.gov/36111813/","publisher":"Scandinavian Journal of Clinical and Laboratory Investigation","year":2022},{"title":"Reference interval of platelet counts and other platelet indices in apparently healthy blood donors in North India according to Clinical and Laboratory Standards Institute guidelines: Need to redefine the platelet count cutoffs for repeat plateletpheresis donation?","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC9855203/","publisher":"Asian Journal of Transfusion Science","year":2022}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"A measure of how much the sizes of your platelets vary. It is a minor extra on some blood counts, and analyzers report it on different scales.","url":"https://bloodtesttracker.com/markers/pdw","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}