Quest Diagnostics offers a variety of diagnostic clinical lab testing, including blood tests, body fluid testing, tissue pathology and cytology, health screening tests, and drug screening. Quest Diagnostics also offers genetic testing. Health care providers, government agencies and employers may order testing through Quest Diagnostics, according to the company's website.
In addition to its diagnostic testing services, Quest Diagnostics develops devices and test kits that enable doctors to detect, monitor and treat certain diseases. The company also provides its services during clinical testing for pharmaceuticals and medical devices, notes Quest Diagnostics. By providing programs that encourage wellness and disease prevention, Quest Diagnostics helps individuals take control of their health.