Epidemiology: Causation & Validity

Question 1

The ideal sample population is a selection of individuals that: __________________________________________ .

Answer 1

reflects the population being studied.

Question 2

When the risk of disease is greater than what a multiplicative effect between two factors would predict, it indicates between the exposures.

Answer 2

Interaction

Question 3

When a variable is associated with the exposure it means that the variable is seen to occur significantly more frequently among the group.

Answer 3

Exposed group

Question 4

A cross-sectional study (can/cannot) establish causality between a risk factor and disease.

Answer 4

Cannot

Question 5

Interaction between exposures can occur when there is a (confounding/causal) relationship between exposure and disease.

Answer 5

Causal

Question 6

When the incidence of disease is due to the direct effect of two different exposures added together, it is referred to as (additive/synergistic) .

Answer 6

Additive

Question 7

Confounding generally occurs when the two groups being compared (are/aren’t) similar to one another

Answer 7

Aren’t

Question 8

When the effect of multiple factors added together leads to a higher rate of disease than expected, it is termed .

Answer 8

Synergism

Question 9

A factor is (necessary/sufficient) in a causal relationship if disease always develops in its presence.

Answer 9

Sufficient

Question 10

A factor is (necessary/sufficient) in a causal relationship if it is needed to instigate the development of disease.

Answer 10

Necessary

Question 11

An association is (sensitive/specific) when a particular factor only causes one disease.

Answer 11

Specific

Question 12

Randomization (does/does not) always eliminate sampling bias.

Answer 12

Does not

Question 13

In (direct/indirect) causation there are intervening factors that cause disease along with the original risk factor.

Answer 13

Indirect

Question 14

When the effect of multiple disease factors added together is less than expected, it is termed .

Answer 14

Antagonism

Question 15

Interaction between risk factors for a disease process (does/does not) depend on the biology of the disease.

Answer 15

Does

Question 16

is one tool that can be used to control selection bias where individuals get selected to enter the study based on chance.

Answer 16

Randomisation

Question 17

The problem with a study with selection bias is that the results might lack (internal/external/internal and external) validity.

Answer 17

Internal and external

Question 18

In order to have internal validity, the two populations being compared must have with the exception of the variable being tested.

Answer 18

similar baseline characteristics to one another

Question 19

If the risk of cancer with one exposure is seven and the risk of cancer with another exposure is three, but the risk of cancer with both exposures is sixty, the relationship is (multiplicative/synergistic) .

Answer 19

Synergistic

Question 20

In order to make sure multiple study groups are similar, the 3 methods we can use are:

Answer 20

randomization, restriction of the study population, and matching

Question 21

Confounding is the term used in a study in which an _________ is the reason for an assumed causal relationship between an independent and dependent variable.

Answer 21

An alternative explanation

Question 22

A confounder is a variable in a study that: _________________.

Answer 22

distorts the true relationship between an exposure and an outcome.

Question 23

When judging an association for , considering alternate explanations ensures that all confounding variables have been taken into account.

Answer 23

Causality

Question 24

If a certain exposure doubles the risk for disease, it is referred to as (additive/multiplicative) .

Answer 24

Multiplicative

Question 25

A necessary and sufficient causal relationship (rarely/frequently) occurs because it is a consequence of a one-to-one relationship of exposure to disease.

Answer 25

Rarely

Question 26

One criteria for causality is , meaning that the exposure to a factor always occurs before the disease develops.

Answer 26

Temporality

Question 27

_____________ refers to a situation in which multiple factors have more than an additive effect on the pathogenesis of disease.

Answer 27

Interaction

Question 28

The strength of an association to determine causality between two variables is measured by the (absolute/relative) risk, or odds ratio.

Answer 28

Relative

Question 29

When looking at the relationship between obesity and heart disease, cholesterol levels can be a third variable, since increase in obesity is typically associated with an increase in cholesterol, which is also associated with an increased risk of heart disease. In this scenario cholesterol levels (is/is not) a confounder.

Answer 29

Is not