RBC indices are calculated* parameters in an automated blood count report. RBC indices have two primary uses:
- Assist with the differentiation of anemias
- Serve as quality control checks
RBC indices include:
- Mean cell (or corpuscular) volume (MCV)
- Mean cell hemoglobin (MCH)
- Mean cell hemoglobin concentration (MCHC)
These parameters identify characteristics of the red cells circulating when the sample was collected.
MCV refers to the average size of the RBCs constituting the sample. Should a mixture of cell populations be present, the sizes of the red cells will be averaged. Reporting units are femtoliters (fL). One femtoliter is 10-15 L. Reference interval for adults is typically 80–100 fL.
Mean cell hemoglobin (MCH) refers to the average weight of hemoglobin in the RBCs in the sample. Should a mixture of cell populations be present, the weights of the evaluated cells will be averaged. Reporting units are picograms (pg). One picogram is 10 -12 grams. The reference interval for adults is typically 26–32 pg.
Mean cell hemoglobin concentration (MCHC) refers to the average hemoglobin concentration in the RBCs contained within the sample. The hemoglobin concentration within the evaluated cells will be averaged if a mixture of cell populations is present. Reporting units are g/dL. The reference interval for adults is typically 32–36 g/dL.
*Some hematology instruments measure MCV directly and derive hematocrit rather than calculating MCV from a measured hematocrit and red blood cell count.
