Epidemiology Intro + Research Questions

Question 1

What does the ‘epi’ mean?

Answer 1

= What is upon

Question 2

What does ‘demi’ mean?

Answer 2

= the people

Question 3

What does ‘ology’ mean?

Answer 3

= the study of

Question 4

What is epidemiology?

Answer 4

The study of the occurrence and distribution of heath related states or events in specified humans, including the study of the determinants influencing such states and the application of this knowledge to control the health problems.

Question 5

What is descriptive epidemiology?

Answer 5

Describing the occurrence and distribution of disease, describing patterns of health and disease in populations.

Question 6

What is analytic epidemiology

Answer 6

Understanding what determinants influence some populations or individuals to be at greater risk of disease due to different risk factors.

Question 7

What risk factors influence susceptibility to disease?

Answer 7

• Age, Sex, Hereditary factors
• Individual lifestyle factors
• Social and community networks
• Education, Agriculture and food production,
  Work environment, living and working
  conditions, unemployment, water and
  sanitation, health care services, housing
• General socioeconomic, cultural and
  environmental conditions

Question 8

What is the order of the hierarchy of evidence of analytical studies?

Answer 8

(Top –> Bottom)

System Review - Metanalysis
Randomised Control Trials (RCTs)
Cohort Studies
Case - Control
Cross - sectional studies
Case series, Case reports
Ideas, opinions, editorials, anecdotal

Question 9

What does PICO (PPEO) stand for?

Answer 9

P - Problem - What is the problem to address

P - Population - Identify the target population
Who? Inclusion, Exclusion

E - Exposure - Risk factor under investigation
What? How? When + intensity,
duration, frequency?

O - Outcome - Disease/Health state What?
How? When + Timing, frequency?

Question 10

What is an example of a PICO question?

Answer 10

E.g.
- Do biphosphates reduce the risk of major
fracture following hip fracture?

• Can aspirin affect ulcer healing in patients
  with venous leg ulcers?

Question 11

What are the 2 areas main study designs can be split into?

Answer 11

Observational study

Experimental study

Question 12

What are the 4 areas that observational studies can be split into?

Answer 12

• Ecological study
• Cross sectional study
• Cohort study
• Case-control study

Question 13

What is the one area that experimental studies can be split into?

Answer 13

= Randomised controlled trial

Question 14

What is the definition of an ecological study design?

Answer 14

An observational study where the exposure and / or disease is observed at a group level.

The group is the unit of observation e.g. group may be defined as hospital / health region etc.

Question 15

What is the definition of a cross sectional study?

Answer 15

A snapshot of the frequency of diseases and exposures in a particular population at a specific time - point.

Question 16

What are the key factors of a cross sectional study?

Answer 16

• a defined population of interest
• a representative sample of individuals
• surveyed at a particular point in time
• obtain simultaneously information on both
  the disease of interest and exposure(s)

Question 17

What is the definition of a cohort study?

Answer 17

An observational study which identifies a group of people and follows them over a period of time to determine incidence of, or mortality from, specific disease(s) and see how their exposures affect their outcomes.

Question 18

What is the definition of a case control study?

Answer 18

A retrospective study which compares how frequently the exposure to a risk factor is present in a group of individuals who have a specific disease (‘case’) and in another group of individuals without the disease (‘control’)

Question 19

What is a randomised control trial?

Answer 19

A study in which a number of similar people from a target population are randomly assigned to 2 or more groups to test a specific drug, treatment or other intervention.

• one group has the intervention being tested
• the other has an alternative intervention
  (the comparison or control group)

The group are followed up to see the effectiveness of the experimental intervention

Question 20

What are positives from randomised control trials?

Answer 20

• Randomisation allows to create two
  comparable groups with the exception of the
  received treatment.
• Control of potential confounders and other
  influential factors as two groups equally
  affected
• No selection bias induced by the recruiter to
  favour one treatment over the other

Question 21

What is experimental design?

Answer 21

Full control of who is exposed, and of the different exposure factors.

(In randomised control trials)

Question 22

What is observational design?

Answer 22

Exposure are not assigned by the researcher, only the observed exposure can be investigated, no control on the unobserved exposure.

(In observational studies -> Cohort studies, Case-control, Cross-sectional studies)