public health Flashcards
What are the 3 domains of public health?
Health improvement
Health protection
Improving services
Define horizontal equity
Equal tx for equal need
Define vertical equity
Unequal tx due to unequal need
Adv and disadv of cohort studies?
Adv - can follow up rare exposures, allows to identify RFs
Disadv - large sample size needed, impractical for rare diseases, expensive
Adv and disadv case-control?
Adv - quick, good for rare outcomes
Disadv - prone to selection and information bias
What is the formula for NNT?
1 over attributable risk
Name some Wilson and jungner screening criteria
Important disease Natural history of disease well understood Simple, safe, precise and validated test Acceptable to population Effective tx from early detection Policy of who should receive tx
Define bias
Systematic differences between groups which may misrepresent the association being investigated
Define reverse causality
The outcome results in the exposure
Name three types of bias
Selection bias
Information bias
Publication bias
Give examples of information bias
Measurement bias, recall bias, reporting bias (don’t report truth)
Define lead-time bias
Early identification doesn’t alter outcome but appears to prolong survival as disease picked up sooner
Define length-time bias
Diseases that progress more slowly/more indolent more likely to be picked up by screening than aggressive cancers with short life expectancy. Therefore screening appears to prolong life.
Define confounding`
When the association between an exposure and outcome is actually due to another factor
What factors make up the Bradford-hill criteria?
Temporality Dose-response Strength Reversibility Consistency
