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Flashcards in Measures of Association Deck (40)
1

what are measures of association

provide mathematical assessment of the relationship between a given exposure and outcome of interest

2

what 2 things do measures of association do

determine if there is an association

measure the strength of the association

3

what type of studies are MOA used in

analytical

4

when comparing exposure groups we assume the exposure is not associated with the disease if:

same amount of disease found in a group of subjects that has the exposure and dont have the exposure

5

when comparing outcome groups we assume the exposure is not associated with the disease if:

same amount of the exposure is found in a group of diseased subjects as non-diseased subjects

6

why use MOA

to make comparisons
- compare exposure groups
- compare outcome groups

7

4 types of MOA

odds ratio

relative risk

attributable risk

prevalence ratio

8

when is odds ratio used

cross-sectional studies
case-control studies

9

what MOA can be used in prospective studies used to compare outcomes

relative risk (incidence ratio)
attributable risk
- prospective cohort studies
- clinical trials

10

when is prevalence ratio used

retrospective cohort studies

cross-sectional studies

11

T/F incidence can be measured in case-control and cross-sectional studies

false

exposure and disease have already occurred

12

odds ratio

ratio of the odds of exposure in the diseased group to the odds of exposure in the non-diseased group

13

odds

ratio of number exposed to number not exposed

14

how do you calculate odds ratio

odds of exposure in diseased group
---------------------------------------------
odds of exposure in the non-diseased group

15

if OR=1

odds of exposure among cases was equal to that of controls

no association

16

if OR>1

odd of exposure among cases was greater than that of control

positive association (prob. causal)

17

if OR

odds of exposure among cases was greater than that of controls

negative association ( possible protective)

18

T/F OR tells you if there is an association and the magnitude of associate

true

19

which observational study design compares exposed to non-exposed

cohort
clinical trials
cross-sectional studies

20

incidence (risk)

measure used to compare the amount of disease that occurs in the exposed and unexposed groups in prospective studies

21

cumulative incidence (attack rate, risk)

number of new cases at the end of the study divided by population at risk at the beginning of study

22

relative risk

used to compare the risk (or incidence) of disease that occurs in the exposed and unexposed groups

23

how do you calculate relative risk

risk of disease in exposed group
--------------------------------------------
risk of disease in unexposed group

24

if RR=1

risk in exposed = risk in unexposed

no association

25

if RR>1

risk in exposed is greater than unexposed

positive association

26

if RR

risk of disease in exposed is less than risk in unexposed

negative association

27

attributable risk (AR)

amount of proportion of overall disease incidence in a population or group that can be attributed to a specific exposure

28

AR interpreted as

% of the overall disease incidence can be attributed to this particular exposure

29

T/F attributable risk is used to quantify an association

false

used to set priorities in disease control programs

30

how do you calculate attributable risk

risk exposed- risk unexposed
--------------------------------------------
risk exposed

31

prevalence ratio

measure used to compare the amount of disease that occurred in the exposed and unexposed groups in retrospective studies

32

prevalence

probability if being diseased

# of diseased/ total # exposed

33

how to calculate prevalence ratio

prevalence of disease in exposed
--------------------------------------------
prevalence of disease in unexposed

34

PR= 1

no association

35

PR>1

positive association (possible causal)

36

PR

negative association (posible protective)

37

which study design uses odds and OR

case-control

38

which study design(s) use incidence and RR

prospective cohort
clinical trial

39

which study design(s) use prevalence and PR

retrospective cohort

40

T/F there are no measures of exposure or association for case reports/series

true