Behavioral science

Question 1

Compares a group of people with disease to a group without disease - looks for prior exposure or risk factor

Answer 1

Case-control study (observational and retrospective)

Question 2

Compares a group with a given exposure or risk factor to a group without such exposure - Looks to see if exposure increases the likelihood of the disease

Answer 2

Cohort study

Question 3

Whats the difference between a retrospective and a prospective cohort study?

Answer 3

Prospective: asks “who will develop the disease”
Retrospective: asks “Who developed the disease”

Question 4

How is prevalence determined from incidence rate and average disease duration?

Answer 4

Prevalence = incidence rate x average disease duration

Question 5

Odds ratio

Answer 5

Odds that the group with the disease was exposed to a risk factor divided by the odds that the group without the disease was exposed

(a/c)/(b/d) or (ad)/(bc)

Question 6

Relative risk (RR)

Answer 6

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

Question 7

Relative risk reduction

Answer 7

The proportion of risk reduction attributable to the intervention as compared to a control

1-RR

Question 8

Attributable risk

Answer 8

The proportion of disease occurrences that are attributable to the exposure
AR = (a/(a+b)) - (c/(c+d))

Question 9

Absolute risk reduction

Answer 9

The difference in risk attributable to the intervention as compared to a control
If 8% of people who receive a placebo vaccine develop the flu vs 2% of people who receive a flu vaccine, then ARR = 8%-2%=6%

Question 10

Number needed to treat

Answer 10

1/ARR

Question 11

Number needed to harm

Answer 11

1/AR

Question 12

Positive skew

Answer 12

Mean > Median > Mode

Tail on the right of the bell curve

Question 13

Negative skew

Answer 13

Mean

Question 14

If the 95% confidence interval for odds ratio or relative risk includes 1…

Answer 14

Null hypothesis is not rejected

Question 15

If the 95% CI for a mean difference between 2 variables includes 0…

Answer 15

Then there is no significant difference

Question 16

If the CIs between 2 groups do not overlap…

Answer 16

Significant difference exists

Question 17

What is the function of a t-test?

Answer 17

Checks differences between means of 2 groups

Question 18

What is the function of an ANOVA

Answer 18

Checks differences between means of 3 or more independent groups

Question 19

What is the function of a chi-square test?

Answer 19

Checks difference between 2 or more percentages or proportions of categorical outcomes (not mean values)

Question 20

Collects data from a group of people to assess frequency of disease at a particular point in time. Asks, “what is happening?”

Answer 20

Cross sectional study (observational)