Intro

Question 1

What is epidemiology?

Answer 1

A quantitative science that looks at health from a population level to address public health goals and to understand cause and effect relationships between certain exposures and disease outcomes.

Question 2

Epidemiology studies…

Answer 2

the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems.

Question 3

Objectives of Epidemiology

Answer 3

• To study the natural history of disease
• To identify causes of disease
• To determine the extent of disease
• To evaluate measures that prevent and treat disease

Question 4

Study Design: Descriptive

Answer 4

Describes only – does not examine relationships 
• Surveillance data
• Case reports
• Surveys
• Case series

Question 5

Study Design: Analytic

Answer 5

Examines relationships / Test hypotheses
Experimental: Investigator assigns exposure Observational: No intervention – investigator observes
• Ecologic
• Cohort
• Cross Sectional
• Case Control

Question 6

Possible Exposure/Disease relationships: Limited evidence of a relationship

Answer 6

Unworthy of study

Question 7

Possible Exposure/Disease relationships: Good evidence of a relationship(more research warranted)

Answer 7

Worthy of Study

Question 8

Possible Exposure/Disease relationships: Strong evidence of a relationship (accepted as causal)

Answer 8

Basis of public policy

Question 9

Hills Causal Criteria

Answer 9

Temporal Relationship
Strength
Dose-Response Relationship Consistency 
Biological Plausibility Coherence 
Experiment 
Analogy 
Specificity

Question 10

Temporal Relationship

Answer 10

Exposure comes before the disease

Question 11

Strength

Answer 11

Magnitude of observed effect

ex. smoking increases risk of lung cancer 10X

Question 12

Dose-Response Relationship

Answer 12

Not always observable

The more you smoke, the stronger the association

Question 13

Consistency

Answer 13

Replication of findings / Is it being observed over and over again?

Question 14

Biological Plausibility

Answer 14

Do we understand the mechanism? Does it seem possible that inhaling smoke into your lungs might cause lung cancer?

Question 15

Experiment

Answer 15

Can we assign study participants to one exposure or another and then follow them for the outcome?

Question 16

Analogy

Answer 16

Supported by similar research

If we see that smoking causes lung cancer, what about another exposure such as asbestos?

Question 17

Modified Determinism

Answer 17

Modified Determinism is a model that explores component, necessary and sufficient causes. It considers sets of exposures or characteristics that are sufficient to cause disease.

Question 18

Necessary Cause

Answer 18

found in all cases

Question 19

Component Cause

Answer 19

needed in some cases

Question 20

Sufficient Cause

Answer 20

the set of necessary and contributing causes that make disease inevitable

Question 21

Causal

Answer 21

The exposure is part of the causal pie leading to disease

Question 22

Chance

Answer 22

There is no association even though one was observed

Question 23

Reverse Causation

Answer 23

The disease causes the exposure

Question 24

Bias

Answer 24

Some aspect of the execution of our study or analytic approach results in us getting the wrong answer

Question 25

Surveillance

Answer 25

What is the problem?
Process begins when a health problem is recognized
For example, we might observe that there is suddenly a large increase in the number of case reports for a specific disease.

Question 26

Risk Factor Identification

Answer 26

What risk factors are associated with a given outcome?

ex. People who inject drugs are 22 times more likely to acquire HIV compared to those who don’t inject drugs

Question 27

Intervention Evaluation

Answer 27

What works?

ex. Surgeon General issues a statement that eating fresh fruits and vegetables and exercising regularly helps prevent heart disease

Question 28

Implementation

Answer 28

How do you do it?