For cholesterol testing, which color-topped evacuated tube should be used?

The red-topped evacuated tube is the appropriate choice for cholesterol testing because it does not contain any additives that might interfere with the measurement of cholesterol levels. This tube typically has a glass or plastic construction and is designed to allow blood to clot naturally. As a result, serum is produced once the blood clots and is centrifuged, making it suitable for various chemistry tests, including lipid profiles.

Cholesterol testing requires serum rather than plasma, which is why tubes containing additives, such as those with anticoagulants (like the lavender or green tubes), are not suitable for this purpose. The light blue tube contains sodium citrate, which is specifically used for coagulation studies, thus making it inappropriate for cholesterol testing as well. In summary, the red tube's design ensures accurate cholesterol measurements by facilitating the separation of serum needed for testing.