What is epidemiology? Flashcards
What is epidemiology?
The study of the distribution and determinants of health related states or events in specific populations
How do communicable and chronic diseases vary in aetiology?
Communicable disease = cause is singular and deterministic e.g. if you get infected with cholera, you will get ill)
Chronic disease = cause is multifactorial and probabilistic e.g. even having a genetic predisposition, smoking, drinking alcohol and a unhealthy diet doesn’t mean you will get the disease but increases risk.
What are the 9 Bradford hill points?
1) strength of association
2) consistently of association
3) specificity of association
4) temporality
5) dose-response
6) plausibility
7) coherence
8) experimental (or interventional) evidence
9) analogy
Is a strong or weak association more likely to be causal?
Strong association
Does a weak association disprove causality?
No
What is consistency of association?
Seeing association between two variables regardless of who is studied and how
What is coherence of evidence?
Does evidence findings match findings from other studies
What is the prevention paradox?
A smaller risk affecting more people produces more cases than a high risk affecting less people so prevention targeted at high risk groups is less effective at reducing cases.
What is attributable risk?
A measure of the proportion of morbidity or mortality that can be attributed to a given exposure
What is background risk?
The base level of risk due to incidence of disease not due to a particular exposure (e.g. the risk of lung cancer in non-smokers based on the incidence of lung cancer in people who never smoked)
What is the relationship between attributable risk and potential for prevention?
Attributable risk = potential for prevention
What is factual exposure and counterfactual exposure?
Factual is what is the current situation/level of exposure/incidence/mortality? and the counterfactual is what would the situation be/level of exposure/incidence/mortality if we implemented an intervention/prevention?
E.g. factual = patients current risk of lung cancer vs counterfactual = patients risk if they stopped smoking