Screening Flashcards
What is screening?
A process of identifying apparently healthy people who may be at an increased risk of a disease/condition. They can then be offered information, further tests or treatment to reduce associated risks or complications
What is the purpose of screening?
To save lives/improve the quality of life through early risk identification. Or to reduce the risk of developing a serious condition or complications
What is the difference between screening and standard healthcare
Screening - NHS initiated, targets asymptomatic people, implies benefits but harm possible.
Standard healthcare - Patient initiated, symptomatic people, no promise of benefit/cure
Name some current screening programmes
Adult - AAA, bowel cancer, breast cancer, cervical cancer.
Compare the screening of AAA and cervical cancer
AAA - Male only, age 65, one off scan. Cervical cancer - Female only, ages 25-64 and scanned every 3 years
Describe the WHO’s criteria for a screening programme
- Recognised need.
- Defined Target population.
- Scientific evidence of effectiveness.
- Quality assured and outline risks.
- Informed choice, confidentiality and respect for autonomy.
- Programme should promote equity and access.
- Benefits outweigh harms.
How can you determine the merit of a screening test?
How it preforms via sensitivity and specificity. How accurate are the results achieved.
What is sensitivity?
How good the scan is at picking up patients who DO have the disease
what is specificity?
How good a scan is at picking up those who don’t have the disease
What are positive and negative predictive values?
Pos - how likely it is you have the disease if pos result.
Neg - how likely it is you don’t have the disease with a negative result.
Look at how to calculate specificity and sensitivity
Specificity - Number if people where disease was not detected/ Number without disease x100.
Sensitivity - Number of results where disease was detected/number of people where disease is present x100.
What are the benefits of screening
Sometimes reduces disease incidence, reduces disease mortality, earlier and less radical treatment, cost-effective and overall population benefit.
What are the potential harms of screening?
False reassurance, over investigation and treatment, anxiety, longer period of knowing about disease with no altered prognosis, potential harm from screening test, increased health inequalities.
what was the marmot review of breast cancer
That UK breast screenings show significant benefit and should continue but communication about the risks/benefits is of utmost importance.
What must doctors include to ensure patients is fully informed
Screening is not mandatory, the purpose, potential risks, burdens, what happens after tests.
