Your doctor will often say to you "I'd like you to have some blood tests". Laboratory tests are among the most important aspects of modern medicine. The Department of Health has estimated that laboratory services contribute to 60-70% of clinical diagnoses. For many conditions, there is no substitute for laboratory tests - for example, high blood cholesterol can be detected by laboratory testing long before any physical symptoms appear.

Doctors rely on the laboratory to help in diagnosing a wide range of conditions, and to help monitor the response to treatment. They trust the results that laboratories produce. But it’s still a reasonable question for patients to ask - "How do I know the laboratory has got my tests right?"

There are many processes in place to ensure that laboratories do produce reliable results. These have been instituted by the Department of Health, laboratory professional organizations and individual laboratories themselves to ensure that quality standards are maintained. There are steps that you can take to further increase your confidence in the quality of your laboratory results, including questions for you to ask your doctor or healthcare provider.