A complete blood count (CBC) is a blood test used to evaluate your overall health and detect a wide range of disorders, including anemia, infection and leukemia.

A complete blood count test measures several components and features of your blood, including:

  • Red blood cells, which carry oxygen
  • White blood cells, which fight infection
  • Hemoglobin, the oxygen-carrying protein in red blood cells
  • Hematocrit, the proportion of red blood cells to the fluid component, or plasma, in your blood
  • Platelets, which help with blood clotting

Abnormal increases or decreases in cell counts as revealed in a complete blood count may indicate that you have an underlying medical condition that calls for further evaluation.

Oct. 18, 2016
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