ABSTRACT
Screening is performed in order to identify whether people have a disease for which they currently have no symptoms. Screening is not carried out to diagnose illness. Instead, it aims to improve the outcomes of those who are affected, by detecting a disease before its symptoms have developed. If the disease can be diagnosed and treated at an early stage, illness and mortality can be reduced. A screening test should be able to detect disease in the period between the time when it can be detected using a screening test and the time when symptoms develop. Since 1996, all new screening programmes have had to be reviewed by the UK National Screening Committee before they can be introduced in the UK and then continue to be reviewed on a regular basis. National programmes in the UK include screening for breast cancer, bowel cancer, cervical cancer, abdominal aortic aneurysm, chlamydia, plus antenatal and neonatal conditions.
