DefinitionRed blood cell (RBC) indices are part of the complete blood count (CBC) test. They are used to help diagnose the cause of anemia, a condition in which there are too few red blood cells.The indices include:Average red blood cell size (MCV)Hemoglobinamount per red blood cell (MCH)The amount of hemoglobin relative to the size of the cell (hemoglobin concentration) per red blood cell (MCHC)See also: RBC countAlternative NamesErythrocyte indices; Blood indices; Mean corpuscular hemoglobin (MCH); Mean corpuscular hemoglobin concentration (MCHC); Mean corpuscular volume (MCV); Red blood cell indicesHow the test is performedBlood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The h