Red Blood Cell Count
Also known as: RBC count; Erythrocyte count; Red count
Formal name: Red Blood Cell Count
Related tests: Complete blood count; Blood smear
The Test Sample
What is being tested?
This test counts the number of red blood cells (RBC) in a sample of whole blood. Red blood cells, which are made in the bone marrow, carry oxygen from the lungs to the cells of organs in the body and transport carbon dioxide from those cells back to the lungs. Women tend to have lower RBC counts than men, while levels may decrease with age. Changes in the RBC count are usually associated with changes in hemoglobin levels. When the values of the RBC count and hemoglobin decrease below the established reference range, the patient is said to be anemic. When the values increase above this range, the patient is said to be polycythemic.
How is the sample collected for testing?
The test is performed on a blood sample taken by a needle placed in a vein in the arm or by a fingerstick (for children and adults) or heelstick (for newborns).
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.
