Week 1

Question 1

sample size can be bigger than population size

Answer 1

if redundant samples are taken

Question 2

probability/random sampling

Answer 2

simple random sampling, systematic sampling, stratified sampling, cluster random sampling

Question 3

Non random sampling

Answer 3

snowball sampling, quota sampling, purposive sampling

Question 4

Proportionate stratified sampling

Answer 4

same proportion from each stratum

Question 5

Disproportionate stratified sampling

Answer 5

different proportion from different strata

ensures minorities are adequately covered

Question 6

HALE

Answer 6

Health adjusted life expectancy

Question 7

DALYs

Answer 7

Disability adjusted life years

Question 8

Attack rate

Answer 8

Percentage of people who were exposed and then got disease

Question 9

Relative risk

Answer 9

risk of disease in those who were exposed relative to non exposed
Attack rate exposed and disease / attack rate non exposed and disease

Question 10

Sufficient cause

Answer 10

factor (or combination of factors ) that will inevitably produce disease
presence of it alone is enough to result in the disease

Question 11

Component cause

Answer 11

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

Question 12

Necessary cause

Answer 12

any agent (or component cause) required for the development of a given disease 
disease is never present when the factor is not present

Question 13

temporality

Answer 13

exposure must precede disease development

Question 14

strength of association

Answer 14

stronger an association is (as described by the relative effect), the less likely it is to be due solely to either bias or confounding

Question 15

consistency

Answer 15

higher consistency, more likely to be causal rather than association

Question 16

dose-response relationship

Answer 16

if a factor does cause a disease, then the risk of developing the disease is likely to be related to the amount or ‘dose’ of exposure; level and duration of exposure

Question 17

reversibility

Answer 17

if you remove the exposure, you remove the outcome

Question 18

Bradford hill criteria

Answer 18

plausibility 
consistency 
reversibility 
strength of association 
temporality 
dose-response

Question 19

data transformation can occur only from

Answer 19

numerical to categorical

Question 20

systematic sampling

Answer 20

divide population size by sample size
round decimal down to give k
select x between 1 and k
x is first number, then every kth number after that

Question 21

reduced risk/lower odds: none

Answer 21

0.83-1

Question 22

reduced risk/lower odds: weak

Answer 22

0.67-0.83

Question 23

reduced risk/lower odds: moderate

Answer 23

0.33-0.67

Question 24

reduced risk/lower odds: strong

Answer 24

0.10-0.33

Question 25

increased risk/higher odds: none

Answer 25

1.0-1.2

Question 26

increased risk/higher odds: weak

Answer 26

1.2-1.5

Question 27

increased risk/higher odds: moderate

Answer 27

1.5-3.0

Question 28

increased risk/higher odds: strong

Answer 28

3.0-10.0

Question 29

upstream work

Answer 29

looking at source and how to prevent disease

Question 30

downstream work

Answer 30

treatment after exposure to disease

Question 31

absolute requirement- bradford hill criteria

Answer 31

temporality

Question 32

strength of association described by

Answer 32

relative effect, OR or RR