As a screening test to evaluate overall health; detect and/or identify a wide range of hematologic disorders; assist in managing medications/chemotherapeutic decisions. The WBC count measures the number of white blood cells and breaks down the different types of cells (neutrophils, lymphocytes, monocytes, eosinophils and basophils). Increased counts suggest infection or inflammation while decreased counts suggest a weakened immune system.The Hemoglobin, RBC and Hematocrit check your level of red blood cells. A deficiency of red blood cells, known as anemia, can impact the oxygen being delivered to your body.Platelets are important for blood clotting. Too many platelets can cause excessive clotting while too few platelets can cause bleeding.