Midterm 2 (Simplified)

Question 1

Definition of epidemiology

Answer 1

The study of the distribution and determinants of health-related states in specified populations, and the applications of this study to control health problems

Question 2

Applications of epidemiology

Answer 2

1. Identifying the cause of a new syndrome
2. Assessing the risks of exposure
3. Determining whether treatment X is effective
4. Identifying health services use needs and trends
5. Identifying practical prevention strategies

Question 3

Definition of endemic

Answer 3

Cases are continually occurring in the population; regularly found among particular people or in a certain area.

Question 4

Definition of epidemic

Answer 4

Outbreak of a disease in a localized group of people; spread by 1. vectors 2. carriers 3. sudden intro of new pathogen

Question 5

Definition of pandemic

Answer 5

Epidemics that have spread beyond their local region and are affecting people in various/all parts of the world

Question 6

Total people living with HIV in 2021

Answer 6

38.4 million

Question 7

Total people newly infected with HIV in 2021

Answer 7

1.5 million

Question 8

Total deaths from AIDS in 2021

Answer 8

650,000

Question 9

Total people infected with TB in 2016

Answer 9

10.4 million

Question 10

Total deaths from TB in 2016

Answer 10

1.8 million

Question 11

Total deaths from HIV + TB in 2016

Answer 11

400,000

Question 12

Prevalence

Answer 12

Proportion of individuals in a population with the disease at a given point in time

Question 13

Prevalence formula

Answer 13

Number of cases/total population

Question 14

Cumulative incidence

Answer 14

Proportion of individuals who become diseased during a specific time period

Question 15

Cumulative incidence formula

Answer 15

Number of new cases of disease in a specific time period/number of people in the population at risk of developing the disease AT THE BEGINNING of the period

Question 16

Incidence rate

Answer 16

Measure of the rate of development of a disease in a population

Question 17

Incidence rate formula

Answer 17

Number of new cases of disease during given time period/number of person time [years/months/days] when people were at risk of developing the disease during observation

Question 18

Sensitivity test

Answer 18

The ability of a test to correctly identify patients with a disease

Question 19

Specificity test

Answer 19

The ability of a test to correctly identify people without the disease

Question 20

Point prevalence

Answer 20

Individuals in a population with disease at a given point in time

Question 21

Point prevalence formula

Answer 21

Number of diseased person on date /population of date

Question 22

Period prevalence

Answer 22

Individuals in a population with disease at any time

Question 23

Period prevalence formula

Answer 23

Cases/population of date

Question 24

Case fatality rate formula

Answer 24

Number of deaths in a given point/total deaths

Question 25

Sensitivity formula

Answer 25

Number of individuals with disease who test positive/number of individuals with disease x 100

Question 26

Specificity formula

Answer 26

Number of individuals without disease who test negatively/number of individuals without disease x100

Question 27

Why is false negatives important (2):

Answer 27

- Could contribute to spread a disease - Treatment delay

Question 28

Why is false positive important (3):

Answer 28

- Patient anxiety - Stigma - Waste of health care resources

Question 29

Standarized rate

Answer 29

Statistical measure of any rates in a population. It is adjusted to take into account the vital differences between populations that may affect their birthrates or death rates

Question 30

Why do we use standard rates

Answer 30

It removes the confounding effect of variables that we know or think differ in populations we wish to compare and it allows us to be able to compare these rates across different countries, locations, or regions

Question 31

John Snow

Answer 31

- English physician widely known for his contributions to cholera - Considered the father of contemporary epidemiology - Developed 2 theories: Miasma & Germ

Question 32

Main aspects of health promotion action (5):

Answer 32

- Build a health public policy - Create supportive environments - Strengthen community action - Develop personal skills - Reorient health services

Question 33

HIV

Answer 33

Human immunodeficiency virus type 1. It causes CD4 T-cell depletion that results in AIDS

Question 34

The epidemiologic approach (3):

Answer 34

- Counting cases and describing them in terms of time, place, and person - Dividing the number of cases by an appropriate denominator to calculate rates (morbidity/mortality) - Comparing the rates over time

Question 35

Crude mortality rate

Answer 35

Overall incidence of death in a population

Question 36

Establishing causation (5):

Answer 36

- Temporality: Exposure must come first Essential - Strength of association: Strong effect? - Biological plausibility: What is the likely biological mechanism? - Consistency: Found across a range of studies? - Dose response: Level and duration of exposure?

Question 37

Prevention Paradox

Answer 37

Seemingly contradictory situation that states that large numbers of people must participate in a preventive strategy for direct benefit to relatively few