Public Health - Screening for Disease Flashcards
what diseases are screened for in adults?
AAA (in Men) Bowel cancer Breast cancer Cervical cancer Diabetic retinopathy
when is bowel cancer screened?
Male and female
50-74 every 2 years
when is breast cancer screened?
Female
50-70 every 3 years
when is cervical cancer screened?
female
25-50 every … years
why is lung cancer not screened?
no good test for pre-malignant change
what is Wilson and Jungjer?
criteria for screening The Condition: - important public health problem - natural history understood - recognizable latent or early symptomatic phase The test: - simple, safe, precise and validated . . The treatment: - effective and available The screening programme: - evidence that screening is effective/accurate . .
are screening and diagnostic test the same?
no
Normal/negative result on screening does not equal disease free
what determines the performance of the screening test?
sensitivity and specificity
how is sensitivity calculated?
= how well the test detects having the disease
= abnormal results/total number of people in disease category X 100
how is specificity calculated?
number of normal results where disease is not detected/total number of people without disease X 100
what is a highly sensitive test?
picks up most of disease
very few false negatives
what is a highly specific test?
correctly detects no disease
few false positives
what are positive predictive values?
how reliable is test result when it shows disease is present
= number of people with +ve test result and have the disease/number of people with positive result X 100
what are negative predictive values?
………….
advantages of screening?
reduced disease incidence cost effective reduced disease mortality . .
