Screening Flashcards
What is screening?
The process of identifying asymptomatic people and testing to identify if they are at an increased risk of a health condition so that preventative action can be taken.
What are the two different types of screening programmes in the UK?
Population screening
Targeted screening
What is population screening?
Universal or mass screening - entire pop or broad section, typically based on demographics (age or gender)
Aims to identify individuals with a particular conditions or risk factor within a general population even is asymptomatic
Reduce burden of disease and prevent its spread.
LArge group low risk
What is a targeted screening programe?
Nationally deliver proactive program - aims to improve health outcomes in people among groups at an elevated risk of a specific condition
Compared to general population targeted group has further risk factors e.g genetic or lifestyle
Inclusion criteria goes beyond age or sex
For example people who smoke regardless of age or sex.
Small group, high risk
What is the high risk approach of disease prevention in screening?
Target wise approach - reduce the risk of a high risk group down to the normal baseline
Focuses on a small population, typically used for rare diseases.
What is the population wide approach in disease prevention in screening?
Aim to reduce everyones risk (often equally) for a conditions
Graph shift left.
Focuses on larger population
What are the key principles of a screening test?
Offered to large number of people - tend to be simple rather than accurate
Look for indicators of an increased risk of disease
If increased risk often requires additional tests to confirm presence or absence of disease/condition
Screening tests cannot diagnose
What are the main aims of a screening programme?
Prevent - early deaths, poor quality of life by allowing early diagnosis and treatment
Reach - everyone in the population
Reduce - chance of developing a serious condition and complications
Provide - information for people to make informed choices about screening and further interventions
What different screening systems exist in NHS England?
Abdominal aortic aneurysm
Bowel cancer screening
Cervical screening
Diabetic eye screening
Newborn screening - NIPE
Screening in pregnancy - (fetal anomlay, infection disease)
What is the generic screening pathway?
Identify people to invite
Discuss and offer screening - if opt again, ask again, if opt out again return to routine invitation
Carry out screening test
Provide and discuss results/options
Carry out diagnostic/confirmatory test if required
Provide and discuss results/options
Offer advice/treatment
What is the purpose of UK NSC recommendations?
List summarise whether population screening is currently recommended for a condition or not and if open to public.
Reviews recommendation regularly, usually every 3 years, suggests who, when and what screening should be offered.
Describes best practice for national screening programmes.
What are the key benefits of screening programmes?
Reduce morbidity, mortality and disabilisty - better future health
(note unable to protect from exposure to disease)
More effective treatment
Reassurance
Informed decision (aka reproductive choice in antenatal screening)
Better use of resources
What are the key drawbacks of public health screening?
Not perfect: false negative or false positives leading to anxiety or false reassurance
Physical harm
Psychological harm
Financial harm
Overdiagnosis
What is over diagnosis as a concept in public health screening?
When screening test identifies person at increased risk - leads to increased diagnosis and treatment
However, no effect on morality rate
Suggests these new cases identified would not have had a harmful effect on health, no benefit from diagnosis/treatment.
Diagnosis of a condition that wouldn’t have caused harm in a person’s life.
What is the role of epidemioogy in screening?
Decide if disease has a natural history that makes screening an option
Disease burden significant enough
Test quality and estimate how ti might perform in the population
Assess potential of a screening programme to improve outcomes
Evaluate the performance of a screening programme in practice
What is the role of health economics in screening?
Is it cost-effective?
Completes cost-effectiveness analysis through measuring costs (Direct, indirect, long term health care)
Measuring benefits (health gains)
Incremental cost-effectiveness ratio (ICER)