Rapid Review Epidemiology

Question 1

How do you interpret the following 95% CI for RR of 0.582: 95% CI 0.502, 0.673

Answer 1

These data are consistent with RR ranging from 0.502 to0.673 with 95% confidence

Question 2

Bias introduced into study when clinician is aware of pt’s Tx type

Answer 2

Observational bias

Question 3

Bias introduced when screening detects a disease earlier and this lengthens the time from Dx to death

Answer 3

Lead time bias

Question 4

If you want to know if geographical location affects infant mortality rate but most variation in infant mortality is predicted by socioeconomic status, than socioeconomic status is a

Answer 4

Confounding variable

Question 5

Proportion of people who have the disease and test positive is the

Answer 5

Sensitivity

Question 6

SEnsitive tests have few false negatives and are used to rule — a disease

Answer 6

out

Question 7

PPD reactivity is used as a screening test because most people with TB (except those who are anergic) will have a positive PPD. HIghly sensitive or specific?

Answer 7

Highly sensitive for TB. Screening tests with high sensitivity are good for disease with low prevalence

Question 8

Chronic disease such as SLE- higher prevalence or incidence?

Answer 8

Higher prevalence-

number of cases in given time period/total # in population at that time period

Question 9

Epidemic such as influenza- higher prevalence or incidence?

Answer 9

High incidence

number of new cases/number of ppl in population at risk

Question 10

Difference between incidence and prevalence?

Answer 10

Prevalence: percentage of cases of disease in a population at 1 snapshot in time
Incidence: percentage of new cases of disease that develop over given time period among the total population at risk

Question 11

Cross sectional survey- incidence or prevalence

Answer 11

Prevalence

Question 12

Cohort study- incidence or prevalence

Answer 12

Incidence and prevalence

Question 13

Case-control study- incidence or prevalence

Answer 13

Neither

Question 14

Describe a test that consistently gives identical results, but results are wrong

Answer 14

High reliability/precisions, low validity/accuracy

Question 15

Difference between cohort and a case control study

Answer 15

Cohort: calculate RR, incidence and/or OR

Case-control: calculate OR- estimate of RR when disease prevalence is low

Question 16

Attributable risk

Answer 16

Difference in rosk in exposed and unexposed grouops (risk that is attributable to exposure)

Question 17

Relative risk

Answer 17

Incidence in exposed group divided by incidence in nonexposed group

Question 18

Results of hypothetical study found an association between ASA intake and risk of heart disease. How do you interpret RR of 1.5?

Answer 18

Pts who took ASA rsk of heart disease was 1.5 times that of pts who did not take ASA

Question 19

Odds ratio

Answer 19

Cohort: odds of developing disease in exposed group divided by odds of developing disease in nonexposed group

Case control: odds taht cases were exposed divided by odds that controls were exposed

Cross-sectional: odds that exposed group has disease divided by odds that nonexposed group has disease

Question 20

Results of hypothetical study found an association between ASA intake and risk of heart disease. How do you interpret OR of 1.5?

Answer 20

Pts who took ASA, odds of acquiring heart disease were 1.5 times those who did not take ASA

Question 21

Which pts do you initiate colorectal cancer screening early

Answer 21

Pts with IBD, FAP, HNPCC

Have first degree relatives with adenomatous polyps (<60 yrs of age) or colorectal cancer

Question 22

Most common cancer in men and most common cause of death in men

Answer 22

Cancer: prostate
Death: lung

Question 23

Percentage of cases within 1 SD of mean? 2 SD? 3 SD?

Answer 23

68%, 95.4%, 99.7%

Question 24

Birth rate

Answer 24

Live births per 100 population in 1 year

Question 25

Mortality rate

Answer 25

Deaths per 100 population in 1 year

Question 26

Neonatal mortality rate

Answer 26

Death from birth to 28 d per 100 live births per year

Question 27

Infant mortality rate

Answer 27

Number of deaths from birth to 1 yrper 1000 live births (neonatal + postnatal mortality) in 1 yr

Question 28

Maternal mortality rate

Answer 28

Number of deaths during pregnancy to 90 days postpartum per 100,000 live births in 1 yr