Lecture 25

Question 1

Temporality:

Answer 1

First the cause then the disease

Question 2

Strength of association

Answer 2

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

Question 3

Consistency of association

Answer 3

Replication of the findings by diff investigators, at diff times, in diff places, with diff methods

Question 4

Biological gradient: dose-response

Answer 4

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

Question 5

Biological plausibility of association

Answer 5

Does the association make sense biologically

Question 6

Specificity of association

Answer 6

A cause leads to a single effect. However, a single cause often leads to multiple effects

Question 7

Reversibility

Answer 7

The demonstration that under controlled conditions changing the exposure causes a change in the outcome.

Question 8

A sufficient cause is:

Answer 8

A factor that will inevitably produce the specific disease.

Question 9

A component cause is:

Answer 9

A factor that contributes towards dis-ease causation, but is not sufficient to cause disease on its own.

Question 10

A necessary cause is

Answer 10

a factor or component cause that must be present if a specific disease to occur.