Environmental Health Resources

Question 1

What is a simple definition of epidemiology?

Answer 1

epidemiology involves trying to find out the causes of illness in a population and what keep people healthy

Question 2

What is environmental epidemiology.

Answer 2

It is concerned with environmental conditions or hazards that may pose a health risk to populations

Question 3

What is a cross-sectional study?

Answer 3

basically a survey. It provides a “snapshot” of the health status of a population at a specific point in time. It does NOT determine cause and effect

Question 4

What are some advantages of Case-control studies?

Answer 4

• examine multiple exposure for 1 outcome
• suited for studying rare diseases
• require fewer cases compared to cohorts, making them less expensive

Question 5

What are some disadvantages of case-control studies?

Answer 5

• not suitable for studying rare exposures
• cannot establish cause and effect since the disease has already occcurred.

Question 6

Standard 2x2 Table

Answer 6

a = exposed with disease
b = exposed with no disease
c = not exposed, with disease
d = not exposed with no disease
N = total size of sample (a+b+c+d)

Question 7

What are the two risks you can calculate using cohort studies?

Answer 7

Risk among people who are exposed and risk among people not exposed

Question 8

How do you calculate risk among people exposed

Answer 8

a+b

Question 9

How do you calculate risk among people not exposed

Answer 9

c+d

Question 10

relative risk calculation

Answer 10

risk among people exposed ÷ risk among people not exposed

Question 11

if relative risk is greater than 1

Answer 11

exposure and disease are positively associated (more exposed people have the disease)

Question 12

if relative risk is equal to 1…

Answer 12

exposure and disease are not associated

Question 13

if relative risk is less than 1…

Answer 13

exposure and disease are negatively associated (more unexposed people have the disease) Those exposed are protected from the disease

Question 14

What are the two odds you can calculate in case-control and cross-sectional studies?

Answer 14

1. The odds of disease among people who are exposed
2. The odds of disease among people who are not exposed

Question 15

What is the odds calculation

Answer 15

of times something happens ÷ #of times it does NOT happen

Question 16

what is the probability calculation

Answer 16

of times something happens ÷ #of times it COULD happen

Question 17

What is the difference between odds and probability?

Answer 17

Odds divides by the time it does not happen, where as probability divides by the number of times it could happen.

Question 18

if the odds ratio is greater than 1…

Answer 18

exposure and disease are positively associated (more disease people exposed)

Question 18

odds ratio equation

Answer 18

oods of disease among people exposed ÷ odds of disease among people not exposed

OR

ad ÷ bc

Question 19

if odds ratio is equal to 1…

Answer 19

exposure and disease are not associated

Question 20

if odds ratio is less than 1…

Answer 20

exposure and disease are negatively associated (more non-deseased people are exposed)

Question 21

What is the incidence rate?

Answer 21

the thing that quantifies how many people have been newly diagnosed during a specific time period - the number of new cases

Question 21

What is the prevalence rate?

Answer 21

The thing that quantifies the number of people who have a particular disease at a defined point in time - the number of people living with the disease

Question 22

How do you calculate the incidence?

Answer 22

of new cases ÷ Population at Risk

Question 23

How do you calculate the incidence

Answer 23

of existing cases ÷ population at risk