Clinical pathology is the laboratory study of cells and tissues. A pathologist identifies the causes and processes of diseases through microscopic study. Some human samples studied under a microscope include tissue specimens, cells, body fluids and secretions. Information gathered from the laboratory study of these samples from the body allow the pathologist to diagnose, confirm and monitor diseases.

Doctor density varies by specialty and location. Washington, D.C. has 14 practicing clinical pathologist in Washington.

According to 2005 Census estimates, Washington, D.C. has a population of 550,521. Of this population, 110,240 are under the age of 18 and 66,591 are at or above the age of 65.