Association, causal interference and causality Flashcards
‘Cause’ definition
A precursor event, condition, or characteristic required for the occurrence of the disease/outcome
3 types of associations
Artifactual (false) associations
Non-causal associations
Causal associations
Artifactual associations can arise from
Confounding and/or bias
Non-causal associations can occur in which ways
The disease may cause the exposure
The disease and the exposure are both associated with a third (confounding) factor
Causal associations
Exposure causes outcome
Sufficient cause
A set of minimal conditions/events that inevitably produce disease
A cause which precedes a disease, and if present, the disease will always occur (quite rare besides genetic. Sufficient causes can still have multiple required “components” termed component causes/risk factors
Necessary cause
A cause which precedes a disease and must be present for the disease to occur. Yet, the cause may also be present without the disease occurring.
Component cause/risk factor
A factor/element that, if present, increases the probability of a particular disease
Synergism
The biological interaction of 2 or more component causes such that the combined measure of effect is greater than the sum of the individual effects
Parallelism
The biological interaction of 2 or more component causes such that the measure of effect is greater if either is present
Multiple causation
multiple component causes working in concert to collectively become sufficient causes
Hills criteria (guidelines)
Strength Consistency Temporality Biologic gradient Plausability
Strength
The size of the measure of association- the greater the association, the more convincing it is that the association might actually be causal
Consistency
The repeated observations of an association in different populations under different circumstances in different studies
Temporality
Temporality reflects that the cause precede the effect/outcome in time
