Epidemiology - Key Concepts Flashcards Preview

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Flashcards in Epidemiology - Key Concepts Deck (24):
1

Define Epidemiology.

The study of the distribution and determinants of health-related states or events in specified population and the application of this study to control of health problems

2

What are the three components of the epidemiological triad?

Time
Place
Person

3

List some factors that are included under the heading of 'Time".

Long-term (secular)
Epidemic (temporary increase)
Periodical (cyclical)
Seasonal

4

List some factors that are included under the heading of 'Place'.

Geographical
Local
Workplace
Community
Home
Social gatherings

5

List some intrinsic & extrinsic factors that are included under the heading of 'Person'.

Intrinsic:
- genetics
- age
- sex
- marital status
- ethnic group

Extrinsic:
- lifestyle
- behaviour
- occupation
- migration
- socio-economic

6

List the 7 stages of the continuum of health.

Healthy
Disease onset
Symptoms
Seek care
Diagnosis
Treatment
Outcome

7

What are the 4 elements of the epidemiologists bathtub?

Incidence
Recovery
Prevalence
Death/Mortality

8

Define incidence.

The rate at which new cases occur in a population during a specific period

9

Define prevalence.

The number of existing cases in a population at a point in time

10

What can affect the prevalence?

Recovery & death

11

How is the incidence rate calculated?

Number of new people with outcome over a time period (either recovery or death) x100000
____________________
Total number of people in the group at risk during that time period

12

How is the prevalence rate calculated?

Number of people with outcome at a point in time x100
____________________
Total number of people in the group

13

What is the difference between point prevalence and period prevalence?

Point prevalence: at one point in time
Period prevalence: over a time period

14

Study designs can be categorised. List the studies that fall under the heading, 'Observational'.

Ecological
Case series
Cros-sectional
Cohort
Case-control

15

Study designs can be categorised. List the studies that fall under the heading, 'Experimental'.

Quasi-experiment
RCT (randomised controlled trial)

16

What is meant by ecological fallacy?

Individual variation in a population

17

How is an ecological study similar to a case-series?

The only difference is that a case-series is individually focused, whereas an ecological study is focused on a population; unit of study is a population as opposed to an individual

18

Give a good example of an ecological study.

John Snow and his discovery of the outbreak of cholera source in London - Broad Street Pump

19

Briefly summarise what a case control study is.

Cases have the disease/condition
Controls don't have the disease/problem
These are the OUTCOMES
Therefore, you need to look BACKWARDS in order to ascertain what proportion of cases and controls had undergone EXPOSURE

20

How is a cohort study similar to a case control study?

A cohort study is also retrospective - look backwards to explore exposure

21

Explain how a cohort study is conducted.

Gather a population free of disease
Expose one group to the disease, leave the other group unexposed
Assess outcome of each group - where is greatest incidence of disease

22

What is a case series?

A series of cases with the same disease (often consecutive)

23

List the 3 steps of conducting a cross-sectional study

1. Sample a population
2. Estimate the proportion - different exposures, signs, symptoms & outcomes
3. Use data for reinforcement and to describe prevalence/explore associations

24

How is a RCT conducted?

Population chosen at RANDOM
One randomly selected group - intervention
The other randomly selected group - control