Screening tests could be loosely defined as proactive rather than reactive. A screening test is performed as a preventative measure – to detect a potential health problem or disease in someone that doesn’t yet have signs or symptoms. The purpose of screening is early detection; helping to reduce the risk of disease, or to detect a condition early enough to treat it most effectively. For example, a person having an HbA1c test for diabetes as part of a screening program could be found to have prediabetes. Diet and lifestyle changes combined with regular monitoring tests can allow someone with prediabetes to avoid developing type 2 diabetes. Screening tests are not usually diagnostic, but are used to identify those who should have additional testing to determine the presence or absence of disease, or people who may benefit from early intervention measures. Screening programs are tailored toward those who the disease is most likely to affect and where the most benefit can be gained. For example, when looking at cervical cancer screening, several factors are taken into consideration in choosing in who to screen including: Sex. Men cannot get cervical cancer (they do not have a cervix!) so only women are tested.

Age. Women below the age of 25 are less likely to be affected by cervical cancer, so the majority of women will be offered the test from the age of 25 (This may differ for some women depending on medical and family history).