Lecture 21: Causality Flashcards Preview

Population Health > Lecture 21: Causality > Flashcards

Flashcards in Lecture 21: Causality Deck (25)
Loading flashcards...
1
Q

What is the definition of the public/population health model?

A

“To provide the maximum benefit for the largest number of people- at the same time reducing inequities in the distribution of health and wellbeing”

2
Q

What is individual healthcare concerned with?

A

The treatment or restoration of health for the individual by a clinician (so it is reactive)

3
Q

What is population health concerned with?

A

The health of groups of individuals, in the context of their environment (a comprehensive, proactive population approach to clinical practice)

4
Q

Does epidemiology determine the cause of disease in an individual?

A

No

5
Q

What does epidemiology determine?

A

The relationship or association between a given exposure and disease in a population

6
Q

Can preventative action be taken before the cause is identified? What is an example?

A

Yes, for example, James Lind’s treatment of scurvy (1747)

7
Q

What are two frameworks to determine causality?

A
  1. Bradford Hill Criteria “aids to thought” 1965

2. Rothman’s Causal Pies

8
Q

What are the seven components of Bradford Hill’s Criteria?

A
  1. Temporality
  2. Strength of Association
  3. Consistency of Association
  4. Biological Gradient (dose-response)
  5. Biological Plausibility of Association
  6. Specifity of Association
  7. Reversibility
    JUDGEMENT
9
Q

What is the weakest component of Bradford Hill’s criteria?

A
  1. Specifity of association, because a single cause often leads to multiple effects
10
Q

Define temporality

A

The cause comes before the disease (essential to establish a causal relation)

Eg smoking comes before lung cancer deaths

11
Q

Define strength of association

A

The stronger the association, the more likely to be causal in the absence of known bias (selection, information and confounding)

Eg smoking/lung cancer risk ratio >10

12
Q

Define consistency of association

A

Replication of the fi dings by different investigations, at different times, in different places, with different methods

Eg multiple studies showed similar results

13
Q

Define biological gradient (dose exposure)

A

Incremental change in disease rates in conjunction with corresponding changes in exposure

Eg increased smoking per day showed higher risk of lung cancer

14
Q

Define biological plausibility of association

A

Does the association make sense biologically?

Eg chemicals in tobacco (carcinogens) are known to promote cancer

15
Q

Define specificity of association

A

A single cause leads to a single effect (often a single cause has multiple effects, however)

Eg smoking has multiple outcomes

16
Q
  1. Define reversibility
A

The demonstration they under controlled conditions, changing the exposure causes a change in outcome

Eg reduced risk in lung cancer after quitting smoking

17
Q

Does causal phenomena usually equal 1:1?

A

No, causal phenomena is usually complex and exposure-outcome relationships are not usually 1:1

18
Q

What is the definition of a cause of disease?

A

An event, condition, characteristic (or combination of these factors) which play an essential role in producing the disease

19
Q

What is the “sufficient” cause of a causal pie?

A

Is a factor/s that will inevitably produce the specific disease (ie causal mechanism or 1 pie)

20
Q

What is a “component” cause of a causal pie?

A

A factor that contributes towards a disease causation but is not sufficient to cause a disease on its own

Eg poor sanitation in regards to TB disease (a slice of pie that’s not necessary)

21
Q

What is a “necessary” cause of a causal pie?

A

A factor (or component cause) that must be present for a specific cause to occur

Eg the TB bug

22
Q

Can you intervene at any number of points in the pie?

A

YES
Knowledge of the complete pathway is not w prerequisite for introducing preventative measures

Ie TB prevention occurred before its cause was discovered

23
Q

What do we use association and several other factors for?

A

To infer causation and to intervene to prevent disease

24
Q

Is a necessary cause still a component cause?

A

Yes, because it’s still part of the pie

25
Q

What do epidemiologists look for links between?

A

Exposure and outcome