Lecture 2

Question 1

The study of the distribution of disease and determinants of disease frequency in populations

Answer 1

Epidemiology

Question 2

The study of “causes” of disease

Answer 2

Epidemiology

Question 3

To control health problems and improve health at the population level

Answer 3

Goal of epidemiology

Question 4

“Counting” the causes of morbidity and mortality.

Answer 4

Operationally

Question 5

Determining variables associated with causes of morbidity and mortality

Answer 5

Operationally

Question 6

• Identifying factors that are “causes” and are potentially modifiable.
• Guiding (and evaluating) interventions to improve public health.

Answer 6

Operationally

Question 7

Do death. disease and disability occur at random?

Answer 7

No

Question 8

Can be identified through the systematic investigation of human populations

Answer 8

Causal factors

Question 9

What can lead to preventive intervention?

Answer 9

Identifying causal factors

Question 10

Good or bad: Chemical, biological, physical, psychological, educational, etc

Answer 10

Exposure

Question 11

Good or bad: disease, cure, improved attitude, longer life, better QOL (quality of life), etc.

Answer 11

Outcome

Question 12

The usual occurrence of a disease in a given population

Answer 12

Endemic

Question 13

A meaningful increase in the occurrence of a disease in a given population.

Answer 13

Epidemic

Question 14

Spread of a disease across a large region or worldwide.

Answer 14

Pandemic

Question 15

exposure of Interest

Answer 15

Independent variable

Question 16

Outcome of interest

Answer 16

Dependent variable

Question 17

Epidemiology is fundamentally concerned with

Answer 17

Populations

Question 18

An identifiable relation between an exposure and a disease

Answer 18

Association

Question 19

Xerostomia is _____ with higher caries incidence.

Answer 19

Associated

Question 20

Incidence rate of oral and pharyngeal cancer is higher among smokers than among nonsmokers

Answer 20

Association example

Question 21

How do we look for a cause?

Answer 21

Methodological question

Question 22

What is a cause?

Answer 22

Ontological questions

Question 23

How do we decide if there is enough evidence to act on a cause?

Answer 23

Ethical question

Question 24

An event, condition, or characteristic that preceded the disease and without which the disease would not have occurred at all or would not have occurred until some later time.

Answer 24

Cause

Question 25

- Strength of the association. - Dose-response relationship. - Temporal sequence. - Biologic credibility. - Consistency of findings across studies

Answer 25

Criteria for assessing causality

Question 26

Is there a strong E – D relationship? | Smoking & lung cancer

Answer 26

Strength of association

Question 27

Does risk increase with increased exposure?

Answer 27

Dose-Response Relationship

Question 28

Does the exposure precede the disease?

Answer 28

Temporal sequence

Question 29

Is there a known biologic basis for the relationship? | e.g., tobacco and lung cancer

Answer 29

Biologic credibility

Question 30

What does biologic credibility depend on?

Answer 30

Current state of knowledge

Question 31

Do multiple studies report similar findings regarding the E – D relationship? (e.g., tobacco and lung cancer)

Answer 31

Consistency of findings

Question 32

What can studies differ by?

Answer 32

- Investigator - Methodology - Study population

Question 33

Identify a disease of interest. Identify exposures of interest “risk factors”. Statistical associations between exp. /disease. Hold constant factors that may be “mixed up” in this measure of association. Infer a causal association. Recommend intervention

Answer 33

Epidemiologic approach

Question 34

Measuring disease occurrence is fundamental in epidemiology.

Answer 34

Quantification in epideiology

Question 35

4 types of scales in quantification

Answer 35

- Nominal Scale - Ordinal - Interval - Ratio

Question 36

Uses names

Answer 36

Nominal scale

Question 37

Follows an order based on severity

Answer 37

Ordinal scale

Question 38

Follows a mathematical order but has no true zero

Answer 38

Interval scale

Question 39

Follows a mathematical order and has a defined true zero

Answer 39

Ratio scale

Question 40

Depending on the time element we can also quantify cases as prevalent or incident by either measuring:

Answer 40

- Prevalence proportion | - Incidence rate

Question 41

Equation for prevalance proportion

Answer 41

``` # of cases / # person in population (at a specific time) ```

Question 42

Specified time interval can be a ‘point’ or ‘period’ of time

Answer 42

Prevalance proportion

Question 43

Forty five (45) D1 students out of one hundred and five (105) have at least one active carious lesion

Answer 43

Prevalence proportion

Question 44

Incidence rate equation

Answer 44

``` # of new cases of disease/population at risk (Over a time period) ```

Question 45

7 new cases of periodontal disease per 105 D1 students in 2010.

Answer 45

Incidence rate

Question 46

Is prevalence a rate?

Answer 46

NO

Question 47

Is incidence a rate?

Answer 47

Yes

Question 48

What does incidence need to be relevant

Answer 48

A time unit

Question 49

Concerned with the number of new cases among persons at risk for a specific follow-up period

Answer 49

Incidence rates

Question 50

With regards to diagnosis, prognosis or | causation, longitudinal studies such as _____________ are appropriate

Answer 50

Cohort studies