Epidemiology Primer

Question 1

Transmission of an infectious diseases from mother to child that occurs in utero is an example of this type of disease transfer

Answer 1

Congenital, lateral

Question 2

The value is most impacted by the prevalence of a disease in a population

Answer 2

PPN

Question 3

This formula is used to calculate the sensitivity of an assay

Answer 3

TP/(TP+FN)

Question 4

Mortality/morbidity

Answer 4

Deaths/illness per 100,000

Question 5

The number of new cases of an infectious diseases that occur within a defined population over a defined period of time

Answer 5

Incidence (in=n=new)

Question 6

The number of active cases at any given time

Answer 6

Prevalence

Question 7

This looks at new cases

Answer 7

Incidence

Question 8

Looks at all current cases alive

Answer 8

Prevalence

Question 9

One that has a relatively stable and expected incidence and prevalence within a geographic area (and population)

Answer 9

Endemic diseases

Question 10

An abrupt and unexpected increases in the incidence of disease over endemic rates

Answer 10

Epidemic

Question 11

Spread of disease beyond continental boundaries

Answer 11

Pandemic

Question 12

How does new effective treatment affect incidence nad prevalence

Answer 12

Nothing on incidence

Decrease prevalence

Question 13

New effective vaccine gains widespread use: incidence nad prevalence

Answer 13

Incidence: decrease
Prevalence: decrease

Question 14

Number of deaths from the condition declines: prevalence and incidence

Answer 14

Incidence: nothing
Prevalence: increase

Question 15

Recovery is more rapid than it was 1 year ago: incidence and prevalence

Answer 15

Incidence: nothing
Prevalence: decrease

Question 16

Horizontal transmission

Answer 16

Passing germs/disease to another person

Question 17

Vertical transmission

Answer 17

Mother to child

Question 18

Likelihood that sick person tests positive

Answer 18

Sensitivity

Question 19

TP+FN

Answer 19

Sensitivity

Question 20

Liklihood a non-sick person tests negative

Answer 20

Specificity

Question 21

TN + FP

Answer 21

Specificity

Question 22

Likelihood that a positive test is found only in sick people

Answer 22

PPV

Question 23

TP + FP

Answer 23

PPV

Question 24

Likelihood that a negative test is found only in non sick people

Answer 24

NPV

Question 25

TN + FN

Answer 25

NPV

Question 26

TP/(TP+FN)

Answer 26

Sensitivity

Question 27

TN/(TN+FP)

Answer 27

Specificity

Question 28

TP/9TP+FP)

Answer 28

PPV

All have P

Question 29

TN/(FN+TN)

Answer 29

NPV

All have N

Question 30

What has a huge impact on positive predicted value

Answer 30

Prevalence of a disease. Doesn’t impact anything else.

Question 31

Collects data from a population to assess frequency of disease (and risk factors) at a particular point in time

Answer 31

Cross-sectional study
What’s happening
Measures disease prevalence

Question 32

Compares a group of people with disease (cases) to a group without disease (controls). Looks for prior exposure or risk factor

Answer 32

Case-control study
Proceeds from effect to cause
Measures odds ratio
Starts with disease

Question 33

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

Answer 33

Cohort study
Proceeds from cause to effect
Measures relative risk
Starts with exposure

Question 34

When are odds ratio and relative risk interchangeable

Answer 34

When prevalence is low

Question 35

Typically used in case-control studies. Odds that group with disease (cases) was exposed to a risk factor divided by the odds that the group without diseas (controls) was exposed

Answer 35

Odds ratio

Question 36

Typically used in cohort studies. Risk of developing disease in the exposed group divided by the risk in the unexposed group

Answer 36

Relative risk q

Question 37

What is an index case

Answer 37

Patient 0