IPS - First Three Sessions

Question 1

Describe stage one of demographic transition.

Answer 1

Total population low, birth rate and death rate fluctuate at a high level.

Question 2

Describe stage two of demographic transition.

Answer 2

Birth rate high, death rate decreasing. Total population increasing.

Question 3

Describe stage 3 of the demographic transition model.

Answer 3

Birth rate decreasing, death rate is low, total population increasing.

Question 4

Describe stage four of demographic transition.

Answer 4

Birth rate and death rate low, total population high but steady.

Question 5

What does the theory of economic transition describe?

Answer 5

As per capita income increases, the population transitions from being mostly employed by agriculture to being employed by industry, services and agriculture. Finally, the population is mostly employed by services.

Question 6

What are two consequences of demographic transition?

Answer 6

An ageing population, and a higher proportion of people with at least one disability.

Question 7

Give one consequence of economic transition.

Answer 7

Unequal distribution of wealth across the globe.

Question 8

What is an SDG?

Answer 8

A sustainable development goal

Question 9

Give three factors that influence population health.

Answer 9

Demographic shape, economic composition, behavioural and lifestyle factors

Question 10

What is the name given to the distribution of a statistic across an infinite number of samples?

Answer 10

The sampling distribution

Question 11

True or false - the sample averages are equivalent to the means of the samples?

Answer 11

True

Question 12

What is the central limit theorem?

Answer 12

The idea that the distributions of the means of the samples have a similar shape regardless of population distribution/size.

Question 13

What is a confidence interval?

Answer 13

Usually the 95% confidence interval, which is the range that is likely to contain the mean of the population values 95% of the time.

Question 14

What two factors influence the size of the 95% confidence interval?

Answer 14

The variation in population values (more variation, wider interval), and the size of the sample (smaller sample, wider interval).

Question 15

True or false - if a sample is precise then it cannot be biased?

Answer 15

False - a sample can be extremely precise yet still be biased.

Question 16

What is selection bias (there are three possible ways for it to occur)?

Answer 16

• Study participants are drawn from a sampling frame that is not representative of the general population. This leads to errors in generalisability.
• Groups compared are not from same population. Errors in comparability.
• One of the groups being studied is not representative of the sampling frame. Errors in comparability.

Question 17

Is generalisability known as internal or external validity?

Answer 17

External. Comparability is internal validity.

Question 18

What are the two categories of bias?

Answer 18

Selection bias and information bias.

Question 19

What are the two types of analytical studies?

Answer 19

Cohort studies and case-control studies.

Question 20

What is risk ratio?

Answer 20

Ratio of “prevalence proportions” of outcome in groups defined by levels of exposure at a particular time. Eg per 1000 person-years.

Question 21

What is rate ratio?

Answer 21

Ratio of incidence rates of outcome in groups defined by levels of exposure after a particular time period. Eg person 1000 person-years.

Question 22

What is odds ratio?

Answer 22

Ratio of odds of outcome in groups, defined by levels of exposure at a particular time.

Question 23

How is prevalence calculated?

Answer 23

Incidence x duration of disease

Question 24

What is a cohort study?

Answer 24

This involves recruiting individuals and classifying them according to their exposure status. They are then monitored for extended periods.

Question 25

What is the difference between a prospective and a retrospective cohort study?

Answer 25

Prospective - individuals who have and haven’t been exposed are recruited and followed up.
Retrospective - individuals recruited then exposure status calculated from historical documentation.

Question 26

What is a case control study?

Answer 26

This involves recruiting disease-free individuals (controls) and diseased individuals (cases) and then calculating their exposure status.