A medical diagnosis requires an overall judgement based on diverse information acquired from questioning the patient, medical examination, testing, etc. Since among all the aforementioned, the results of testing--particularly those of investigating the specimen--are expressed in numerical values, they have a high level of objectivity. Therefore, we have become able to carry more objective and accurate medical examinations based on data from such testing. At present, among the types of such testing, we mainly handle blood corpuscle calculation equipment used in hematological testing. That is because hematological testing is indispensable in health check-ups, as well as in the medical examination and treatment of illness. As blood circulates to every nook and corner of the body through the heart's pumping operations, it reflects the state of the health of the body's organs and structure. For this reason, if the blood is measured, the fundamental level of the health of a person's body can be known. Since some change will appear as well in the components of the blood when there is an abnormality somewhere in the body, blood testing allows plans for more appropriate medical care to be devised for all types of illness and injury when they arise. In this way, hematological testing is a fundamental and absolutely indispensable test in health check-ups, as well as in both the medical examination and treatment of ailments. Therefore, it is always conducted during health examinations and complete physical check-ups. Especially with animals, young children, and others who can not express their physical ailments very well on their own, accurate testing is extremely important. The seriousness of an illness sometimes advances without any connection to the symptoms, so early medical examinations and treatment are considered necessary and testing is greatly relied on.