Behavioural and Biostats Flashcards Preview

STEP 1 > Behavioural and Biostats > Flashcards

Flashcards in Behavioural and Biostats Deck (20):
1

Collects data from a group of people to assess frequency of disease and related risk factors at a particular point in time

cross sectional study

2

compares a group of people with disease to a group without disease to look for prior exposures or risk factors

case control

3

compares a group with a given exposure or risk factor to a group without such exposure to see if exposure increased likelihood of disease

cohort

4

case control study calculates what

OR

5

cohort study calculates what

RR

6

cross sectional study calculates what

prevalence (NOT incidence)

7

clinical trial phase: is it safe?

phase 1, small number of healthy volunteers

8

clinical trial phase: does it work?

phase 2: small number of patients with disease of interest

9

clinical trial phase: is it as good or better?

phase 3: large number of patients randomly assigned to either treatment or placebo/best treatment available

10

clinical trial phase: can it stay?

phase 4: postmarketing surveillance of patients after treatment is approved

11

how does prevalence affect PPV and NPV?

increasing prevalence increases PPV and decreases NPV

12

odds ratios are used in what kind of studies

case control

13

relative risk is used in what studies

cohort studies

14

OR formula

how many people with disease had exposure

A/C / B/D

15

RR formula

how many people with exposure got disease

a/(a+b) / c/(c+d)

16

Attributable risk formula

proportion of disease attributable to the exposure

a/a+b - c/c+d

17

relative risk reduction formula

proportion of risk reduction attributable to intervention

1-RR

18

absolute risk reduction forumula

difference in risk attributable to intervention vs. control

c/c+d - a/a+b

19

number needed to treat formula

number of patients who need to be treated for1 1 person to benefit

1/ARR

20

number needed to harm formula

number of patients who must be exposed to a risk factor for 1 patient to be harmed

1/AR