The work of the clinical laboratory professional - who analyzes many things in the body including chemical indicators, the health of blood cells, and the presence of microbes and genetic markers - has long been an unseen aspect of health care. Yet, clinical lab tests often provide the link between the patient's presentation of symptoms and the doctor's diagnosis of and prescribed treatment for a particular condition or disease. Through preventive screening, lab tests also aid in the early detection of potentially fatal conditions and, in so doing, lead to early treatment. In short, lab tests can help both to save lives and to improve the quality of life.

Lab Tests Online has been designed to help you, as a patient or family caregiver, to better understand the many clinical lab tests that are part of routine care as well as diagnosis and treatment of a broad range of conditions and diseases. If you are a medical professional, this site can serve as a quick reference tool or as a resource for keeping up with advances in laboratory science. Our Features page describes what you can find on the site and how it can benefit you.

The site is the product of a collaboration of professional societies representing the laboratory community. When we launched this site in 2001, it was a time when health care consumers were being asked to assume more responsibility for their care. Today, knowing more about lab tests and the issues surrounding testing is an important part of fulfilling this responsibility.

Since its launch, Lab Tests Online has helped millions of users learn about their tests and discuss them more clearly with their doctors. To ensure that the site is accepted as a trusted source for medical information, we adhere to the principles espoused by the Health on the Net Foundation, an international not-for-profit organization that seeks "to guide lay persons or non-medical users and medical practitioners to useful and reliable online medical and health information." We also support the Consumer Reports WebWatch guidelines to promote credible information practices on the web.

This site would not be possible without the many volunteer hours provided by members of our Editorial Review Board, nor the financial support of our sponsors. We would also like to acknowledge the contributions of numerous members of the laboratory community who wrote, edited, or reviewed the material found on the site as well as the many online and offline resources used by our writers in their research. You can typically find these resources listed at the end of each article under "Sources."