Blood Test – Meaning and Scope

According to the dictionary definition, “blood test is an analysis of a sample of blood, especially for diagnostic or therapeutic purposes. It is a process of obtaining blood for such a test.”

Blood tests are very useful diagnostic tools. Blood composes of different kinds of cells and other compounds including various salts and certain proteins. A blood test is a laboratory analysis which is performed on a blood sample that is usually extracted from a vein or an artery in the arm using a needle or a pin-prick.

There are three main components of blood viz., plasma, white blood cells, red blood cells and platelets. When the blood is drawn out of the body, it starts clotting and becomes solid. The remaining liquid portion is called serum. It is used in chemical tests and in research to find out how the immune system fights diseases.

Blood tests are a laboratory activity and are used to determine the physiological and bio-chemical states including diseases, mineral content, drug effectiveness and organ function. Although the term blood test is used in a more generic reference related to all tests with blood, but most of the tests are done on plasma or serum instead of the blood cells.

The most common types of blood tests are:

• Full Blood Count – For anemia
• Kidney & Liver Function
• Blood Sugar Level
• Blood Clotting Test
• Blood Cholesterol
• Blood Grouping
• Thyroid Function