Causality Flashcards
What are the main features of the Bradford Hill Criteria?
Strength of association, specificity, temporal sequence, consistency of association, dose response and reversibility (so sick & tired, can’t do revision)
Describe strength of association
A strong association is more likely to be causal and less likely to be explained by bias or confounding
Describe specificity of association
If the association is specific to the exposure it suggests that the outcome under investigation is more likely to be causal
Describe the consistency of association
An association that has been demonstrated by different studies on different groups of people in different places at different times is more likely to be causal
Describe temporal sequence
An association in which exposure to the putative factor has been demonstrated to precede the outcome of interest is more likely to be causal
Describe dose response
Association in which varying amounts of exposure to the putative factor lead to varying strengths of association with the outcome of interest
Describe reversibility
Association in which removal or prevention of the putative factor leads to a reduced or non-existent risk of acquiring the outcome
What are the weaker features of the Bradford Hill Criteria
Coherence of theory, biological plausibility, analogy
Describe coherence of theory
Association that conforms with current knowledge and theory is morel likely to be causal
Describe biological plausibility
Association for which there is a biologically plausible mechanism is more likely to be causal
Describe analogy
Association for which an analogy exists is more likely to be causal
What are the two assumptions made by the Bradford Hill Criteria?
Disease doesn’t occur at random and that the disease has causal and preventative factors which can be identified through systematic investigation
