Which tube color is typically used for CBC testing due to its additive?

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Multiple Choice

Which tube color is typically used for CBC testing due to its additive?

For a complete blood count, the sample must stay un-clotted so cell numbers and characteristics can be accurately measured. The additive that achieves this best is EDTA, which binds calcium and stops the clotting process without harming the cells. The lavender (purple) top tube contains EDTA, making it the standard choice for CBC because it preserves both the counts and the cell morphology needed for reliable results. Other colors serve different tests: red tops lack anticoagulant or have clot activator, green tops use heparin for plasma chemistry, and gray tops contain fluoride/oxalate for glucose testing. So the lavender EDTA tube is the right pick for CBC.

For a complete blood count, the sample must stay un-clotted so cell numbers and characteristics can be accurately measured. The additive that achieves this best is EDTA, which binds calcium and stops the clotting process without harming the cells. The lavender (purple) top tube contains EDTA, making it the standard choice for CBC because it preserves both the counts and the cell morphology needed for reliable results. Other colors serve different tests: red tops lack anticoagulant or have clot activator, green tops use heparin for plasma chemistry, and gray tops contain fluoride/oxalate for glucose testing. So the lavender EDTA tube is the right pick for CBC.

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