What is a common specimen type for blood typing?

The most common specimen type for blood typing is serum from a red top tube. This is because blood typing involves determining the ABO and Rh blood groups, which can be effectively accomplished using serum, as it contains the antibodies necessary for the agglutination reaction that identifies blood types. Red top tubes allow for the blood to clot, thereby separating the serum from the cellular components of blood after centrifugation.

Whole blood in an EDTA tube could also be used for blood typing, but the presence of anticoagulant might interfere with some tests. Plasma from a blue top tube, primarily used for coagulation studies, is not ideal for blood typing purposes. Capillary blood from a fingerstick is generally not used for blood typing due to potential contamination and lower volume, which may not provide sufficient material for accurate typing.

This context highlights the use of serum as the preferred specimen, illustrating why it is the most suitable choice for blood typing in a clinical setting.