Session 2

Question 1

What are some of the features of a census?

Answer 1

• It refers to universal sources of information.
• The population sits between birth and death registration.
• A census refers to both households and people.
• It has a universal coverage and it occurs at regular intervals - every 10 years in the UK.

Question 2

What can a census tell us?

Answer 2

• Population size
• Population structure e.g. service needs
• Population characteristics such as unemployment, overcrowding, lone pensioners, single parents etc.
• It allows the government to plan services.

Question 3

What is population size and structure measured by?

Answer 3

• Births
• Deaths
• Migration

Question 4

How do you calculate the crude birth rate?

Answer 4

The number of live births per 1,000 population.

Question 5

What is the general fertility rate?

Answer 5

The number of live births per 1,000 females aged 15-44 years.

Question 6

What is the total period fertility rate?

Answer 6

The average number of children that would be born to a hypothetic woman in her life.

Question 7

What are some of the links between Crude Birth Rates (CBR), General Fertility Rates (GFR) and Total Period Fertility Rates (TPFR)?

Answer 7

• Low CBR is due to low GFR.
• High CBR is due to high GFR and a high proportion of 15-44 year olds in London.
• GFR is affected by Age Specific Fertility Rates (ASFR).

Question 8

What are the determinates of fertility?

Answer 8

Fecundity = the physical ability to reproduce.
High sterilisation and hysterectomies will mean low fecundity.
Fertility = the realisation of this potential as births.

Question 9

What are some factors that can effect fertility rates?

Answer 9

High sexual activity = high fertility.
High economic climate = high fertility.

High contraception = low fertility.
High abortion rate = low fertility.

Question 10

What do crude birth rates tells us?

Answer 10

The impact of births on the size of the population.

Question 11

What do general fertility rates tell us?

Answer 11

They compare the fertility of fertile female populations.

Question 12

What do total period fertility rates tell us?

Answer 12

They compare the fertility of fertile females without being influenced by age group structure.

Question 13

How do we calculate Crude Death Rate?

Answer 13

This is the number of deaths per 1,000 population.

Question 14

How do we calculate age specific death rates?

Answer 14

This is the number of deaths per 1,000 in an age group.

Question 15

How do we calculate the Standardised Mortality Ratio?

Answer 15

This compares the ‘observed’ number of deaths with the number of expected deaths if age-sex distribution of populations were identical.

Question 16

What are some of the reasons for collecting mortality data?

Answer 16

• Classifying the causes of death
• Analysing patterns in mortality rates
• Identifying health problems
• Informing service needs.

Question 17

What are some of the variable effecting population estimates and projections?

Answer 17

• Immigration (big issue at the moment!)
• Births
• Deaths

Question 18

What are Population Estimates?

Answer 18

This is applying what is known about births, deaths and migration to the present.

Question 19

What are population projections?

Answer 19

These are estimates about future populations. There are additional assumptions about births, deaths and migration in the future.

Question 20

Why do population estimates and projections depend on?

Answer 20

• Migration

- Fertility Rates - remember that fertility is difficult to predict because it is determined by social behaviour.

Question 21

How is healthcare information used to identify health and healthcare needs?

Answer 21

There are a few key questions that need to be answered, e.g.
- How common?
- How serious?
- How expensive?
Morbidity data is key to discovering health care needs.
NHS expenditure should map into the healthcare needs of the country.

Question 22

How do you calculate a trend?

Answer 22

A trend involves a comparison of rates which require;

• A Numerator (TOP)
• A demoninator (BOTTOM)

Question 23

Name some numerator and denominator errors.

Answer 23

Numerator errors;

• Death certification
• Disease diagnosis
• Classification or coding errors

Denominator errors;

• Population used
• Population definition
• Population count or estimate.

Question 24

When you interpret healthcare data what are some of the things you should consider?

Answer 24

Chance (random variation)
Artefactual (systematic) errors - such as numerator errors and denominator errors.
Real phenomenon - ‘natural’ epidemiological causes and medical care affects.
If there is a dramatic chance consider mistakes before you think of it as a real phenomenon.

Question 25

What are some contentious issues with the use of health information?

Answer 25

• Ethical issues
• Methodological issues; completeness/duplication, accuracy, variations of diagnosis and disease, etc
• Confidentiality
• Recording linkages

Question 26

What is the definition of a census?

Answer 26

‘The simultaneous recording of demographic data by the government at a particular time pertaining to all the persons who live in a particular territory’.