EPH 2021 Demography and Epidemiology
Case 1 summary: What is demography?
Learning goals:
1. What is demography?
2. What is the difference between demography and epidemiology?
3. What are the measurements of demography?
a. How do demographers choose their measures, what do they focus on?
4. What are the determinants of demographic change?
5. What are the causes and consequences of demographic change?
a. Consequences specifically for public health
6. Changes in fertility, life expectancy and migration over the years in Europe (explain graphs)
7. Why are demographic changes relevant for public health in Europe?
1. What is demography?
- Demography = scientific study of human population
o Including size, distribution, composition, and the factors that determine the three
o Demography focuses on five aspects of human population
Size
Distribution (spreading in geographic space)
Composition (sex, age …)
Population dynamics
Socioeconomic determinants & consequences of population change
o Ascribed characteristics = Characteristics that do not change in the lifetime
E.g. age, sex, race, year of birth…
o Achieved characteristics = can change in the lifetime
E.g. nativity, ethnicity, ancestry, religion, citizenship, marital status, household characteristics, living
arrangements, educational level, school, enrolment, labor force status, income, and wealth
- Basic demography: about theoretical and empirical questions of interest to other demographers
- Applied demography: focused on practical questions of demography of interest to people outside of demography
2. What is the difference between demography and epidemiology?
- Demography is concerned with size and characteristics of a population and with understanding population dynamics
o Demography: also social aspects, epidemiology focuses on health part of the population
o More macro level (the aggregate level)
- Epidemiology is theory or science concerned with studying the frequency with which phenomena (diseases) occur in a
population
o Epidemiologists are less interested in population in itself and more in the diseases that affect individuals.
o more focused on the ‘micro-level’ (the level of individuals)
3. What are the measurements of demography?
a. How do demographers choose their measures, what do they focus on?
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,EPH 2021 Demography and Epidemiology
- Censuses
o Basic questions about age, sex, marital status, and place of residence, data on other characteristics such as
employment, education and housing
o Also for small areas and population subgroups
o PRO
Tool for collecting data on population stock for population subgroups
Widely used to assess mortality levels and trends
o CONTRA
Huge costs and challenge of ensuring acceptable data quality
Requires reasonable administrative infrastructure and also cooperation of the population to be
enumerated
Errors and omissions (e.g. under-enumeration)
- Vital registration
o Most high-income countries have well-established registration systems with complete, or very near complete,
coverage
o In poorer parts of the world, however, vital registration systems are frequently seriously incomplete or non-
existent, although there are exceptions and some countries, including India and China, have sample
registration systems for selected areas
- Cause of death
o Death certificated = major source of information on cause of death
- Other data sources
o E.g. range of surveys
4. What are the determinants of demographic change?
- 3 demographic determinants
o Fertility is most important. Every birth represents an addition to current generations as well as potential
augmentation of future generations.
o Death is not as important as it has an impact on age structure
o Migration has an effect on population size and age structures
Affects other demographic parameters because migrants differ from the general population
International migrants are generally young and in good health thus they may temporarily rejuvenate
the host population and increase fertility while decreasing mortality
Mortality of immigrants is often lower than that of the hosting population
5. What are the causes and consequences of demographic change?
a. Consequences specifically for public health
Causes of demographic change Consequences of demographic change
- Fertility and infant mortality birth and death - health spending (varies by age, race and
rates ethnicity)
- urbanisation: job opportunities, school etc. - ageing populations long term care for older
- internal and external migration people
- economic situations - job offers (economics) SES inequalities
- war - lack of workforce (also in healthcare)
- political and social change
- famine
- natural disasters
- medicine and hygiene
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,EPH 2021 Demography and Epidemiology
6. Changes in fertility, life expectancy and migration over the years in Europe (explain graphs)
Graph 1: Around 1910, there was a sharp decrease in the
total fertility for Germany as well as for Slovenia. This can
be caused by increased life expectancy because of
increased knowledge about medicine3s. Also, this can be
caused by WW1, since acute stress can have an influence
on fertility as well.
- Definitions
o Fertility: the childbearing performance of
individuals, couples or populations
o Fecundity (Fruchtbarkeit): the physiological capability of producing birth
o Parity: the number of children previously born alive to a woman or couple
Nulliparious woman: have not given birth to a child
- Determinants of fertility
o Proportion of women married (exposed to risk)
o Contraceptive use
o Induced use
o Postpartum-non susceptibility to conception
o Hygiene
Graph 2: There’s a sharp decrease in life expectancy in
1920. This can be caused by WW1. After this decrease in
life expectancy. There was another sharp decrease in life
expectancy around 1945. This can be caused by WW2.
Spanish flu had a big influence on life expectancy as
well in 1920
Graph 3: We can see that the international migrant
stock increases. Around 2010 - 2015 this increase
became less steep. Also, in 2015, the international
migrant stock became higher than the international
migrant stock of the United States. Labour migration → fall
of berlin wall.
7. Why are demographic changes relevant for public health in Europe?
- Describe changes in population size, distribution, and composition as a guide for decision making
- Detect patterns
- Describe the distribution of the population in space, its degree of concentration or dispersion, the fluctuations in its
rate of growth, and its movements from one area to another
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, EPH 2021 Demography and Epidemiology
- To predict the future
- Review the past
- Size and characteristics to measure health and needs of population
o See what healthcare need the future population has
o Developing theories of population change
o Analyzing causes and consequences of population trends
- Decision making also based on needs
o E.g. demographic change more elderly less younger people means decision to spend more money on elderly
care and diseases occuring more often in elderly people
o or migration, decision about job opportunities, or infectious diseases with foreign countries as origin (TBC).
- International migration can be a good tool, you can fill in some employment aspects (low skilled jobs)
o Migrant usually have higher fertility rates → can solve the problem NL is facing with high population age and
declining birth rates
o generally better health when it comes to chronic diseases, but may spread infectious diseases
- dependent populations: 0-15 and 65+ years
o not working; but often voluntary work social contribution
- independent populations: 0 – 64 years
o working
Case 2 summary: Making sense of labels: migrants, refugees and expacts
Learning goals:
1. What are the categories of migration?
a. Why is it important to have different categories regarding migration?
b. What are the different terms for migrants?
i. What problems could the different terminologies cause?
2. What are the reasons for migration?
a. What are the potential push and pull factors?
3. How does migration affect demography in Europe?
1. What are the categories of migration?
- Migration: movement of people from one administrative area to another, which can be internal (within a country) or
external (between countries)
- internal migration: moving within a state, country, or
continent
- external migration: moving to a different state, country, or
continent
- emigration: leaving one country to move to another
- immigration: moving into a new country
- return migration (circulatory) moving back to where you
came from
- seasonal migration: moving with each season or in response
to labor or climate conditions
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