Introduction to screening
Primary- preventing disease by controlling risk factors
Secondary- Apply measures to detect early departure from health and introduce appropriate treatment and interventions accordingly
Tertiary- apply measures to reduce/eliminate long term impairments and disabilities caused by disease. Aims to minimise suffering and allow patients to adjust to their condition
Screening
- = Presumptive identification of unrecognised disease in an apparently healthy, asymptomatic population by means of tests, examinations or other procedures that can be applied rapidly and easily to the target population
- Done in those who are thought to be healthy
- Testing people before becoming symptomatic
- Preclinical phase of disease- when disease is asymptomatic but can be detected through a marker in testing
- Applied to the whole population - mass screening
- Case finding - doctors opportunistically find conditions within patients
- As patients being screened are ‘healthy’ screening tests must be cheap, widely available and non invasive to increase update
- Positive screening test - does NOT mean patient has the disease, just increased likelihood of having the disease - requires further screening
Case finding
- Technically not screening - purely opportunistic
- Patient goes to see HCP for a reason, and at same time HCP also check patient for another condition
- Still used to increase diagnostic coverage
Targeted screening