Preventative Medicine

Question 1

What is distribution?

Answer 1

A description of frequency, counts, rates or risks

Question 2

What do descriptive studies do?

Answer 2

Describe cases

Describe populations

Question 3

What is the purpose of descriptive studies?

Answer 3

To know how much disease a region or group has

Question 4

What are the pros of an anecdote and case series?

Answer 4

Quick
Easy to perform in clinic
Provides new, previously unobserved conditions
Provides new potential risk factors

Question 5

What are the cons of an anecdote and case series?

Answer 5

Not scientific and unable to test a hypothesis
Seriously affected by observer bias
Difficult to make inference about disease cause

Question 6

What does a cross sectional survey observe?

Answer 6

A snapshot of people with an outcome

Question 7

What are the pros of a cross sectional survey?

Answer 7

Quick

Good at estimating prevalence or burden

Question 8

What are the cons of a cross sectional survey?

Answer 8

One represents that point in time
Cannot estimate incidence
Sampling frame may lead to bias

Question 9

What does the counterfactual method ask?

Answer 9

If the disease would have happened at the same time in the same person and if the factor was not present

Question 10

What are the pros of ecological studies?

Answer 10

Less expensive
Less prone to bias
Easy to perform 
Provides new hypothesis about the causes of a disease or condition
Provides new potential risk factors

Question 11

What are the cons of ecological studies?

Answer 11

Ecological fallacy

Assume that the averages apply to all individuals

Question 12

These types of studies are retrospective and happen after the disease has been diagnosed

Answer 12

Case control study

Question 13

What does it mean if the odds ratio is 1

Answer 13

No effect

Question 14

What does it mean if the odds ratio is >1

Answer 14

There is an association

The exposure raises the risk of disease

Question 15

What does it mean when the odds ratio is

Answer 15

There is an association

The exposure lowers the risk of disease

Question 16

What are the pros of case control studies?

Answer 16

Good for rare disease and rare exposures

Quick

Question 17

What are the cons of case control studies?

Answer 17

Prone to selection bias
Especially prone to participation bias
Finding a suitable control group can be difficult
Difference to recall leads to bias

Question 18

Which is the best observational study?

Answer 18

Cohort study

Question 19

What are the requirements for candidates of a population study?

Answer 19

Must be at risk for the outcome

Free of the outcome at the start

Question 20

What are the pros of cohort studies?

Answer 20

Good for rare exposures
Can look at multiple outcomes
Reduces information bias
Direct measurement of incidence

Question 21

What are the cons of cohort studies?

Answer 21

Inefficient for rare diseases
Expensive
Loss of follow up

Question 22

What is a randomised controlled trial also known as?

Answer 22

A clinical trial

Question 23

What does a randomised controlled trial test?

Answer 23

How well an intervention works

Question 24

What are the pros of randomised controlled trials?

Answer 24

Strongest evidence for causality
No selection bias
Less observer bias

Question 25

What are the cons of randomised controlled trials?

Answer 25

Not real life
High cost
Inappropriate/unethical for many research questions

Question 26

What is error?

Answer 26

The difference between an estimated/measured value and true value

Question 27

What are some sources of error?

Answer 27

Study design
Data collection
Data management
Sample collection
Lab analysis

Question 28

What is bias?

Answer 28

Systematic non random deviation of result and interferences from the truth or processes leading to such a deviation

Question 29

What is diagnostic bias?

Answer 29

When diagnosis is made based on exposure

Question 30

What is self selection bias?

Answer 30

When subjects make decisions

Question 31

What are the different types of information bias?

Answer 31

Recall
Interviewer
Surrogate

Question 32

What are the three categories of prevention?

Answer 32

Primary
Secondary
Tertiary

Question 33

What is the aim of primary prevention?

Answer 33

Prevent the onset of disease

Question 34

What is the aim of secondary prevention?

Answer 34

Halt the progression once started

Question 35

What is the aim of tertiary prevention?

Answer 35

Limit disability and complications established in disease

Question 36

What is Rose’s Population Theory?

Answer 36

an approach to preventive medicine and public health which predicts that shifting the population distribution of a risk factor prevents more burden of disease than targeting people at high risk

Ie shift the mean to the left

Question 37

What does the population mean predict?

Answer 37

The prevalence of cases

Question 38

What is the prevention paradox?

Answer 38

The majority of cases of a disease come from a population at low or moderate risk of that disease, and only a minority of cases come from the high risk population (of the same disease). This is because the number of people at high risk is small.