In the clinical examination of blood, either venous blood can be drawn for examination or fingertip blood can be taken for examination, also known as peripheral blood. If the blood sampling method is taken correctly, there is usually no significant error in the results of these two blood collection methods, but if the fingertip blood is taken with excessive squeezing of the finger, or if the site of blood collection happens to be tied to a deeply located artery, the results of venous blood and fingertip blood will show some errors. First, due to excessive squeezing, some of the tissue fluid will enter the blood specimen and the blood specimen may get diluted and the number of various blood cells will appear to be relatively reduced, while venous blood is more stable and most closely resembles the true cellular level of the body. The possible error between venous blood and fingertip blood is that the number of various blood cells in fingertip blood will appear to be low.