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The Clinical Measurement Ontology (CMO), Measurement Methods Ontology (MMO), and Experimental Condition Ontology (XCO) are currently being developed at the Rat Genome Database. For more information about these vocabularies please see Shimoyama et al. Three ontologies to define phenotype measurement data. Front Genet. 2012;3:87. Epub 2012 May 28 or contact us (

Term:red blood cell distribution width- standard deviation
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Accession:CMO:0003232 term browser browse the term
Definition:Red blood cell distribution width- standard deviation (RDW-SD) is a measurement derived from the red blood cell distribution curves generated on automated hematology analyzers and is an indicator of variation in RBC size within a blood sample. The RDW is used along with the indices (MCV, MCH, MCHC) to describe a population of RBCs. The RDW measures the deviation of the RBC width, not the actual width or size of individual cells. The RDW-SD is an actual measurement of the width of the red cell distribution curve in femtoliters (fL). The width of the distribution curve is measured at the point that is 20% above the baseline. Since the RDW-SD is an actual measurement, it is not influenced by the MCV and more accurately reflects the red cell size variance.
Synonyms:exact_synonym: RDW-SD

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Related Phenotype Data for Term "red blood cell distribution width- standard deviation" (CMO:0003232)

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  clinical measurement 2369
    blood measurement 439
      complete blood count and differential 11
        red blood cell morphological measurement 0
          red blood cell distribution width- standard deviation 0
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