Lecture 3:
Public health indicators:
Demographic indicators
1
Public health indicators
Represent complex (synthetic) numerical expression of the impact of a social factor or the simultaneous action of a group of social factors and/or health determinants on the state and dynamics of demographic, health and social status of the population.
They are applied to describe, evaluate and analyze the state and dynamics of health of the population or some groups of the population.
2
Main groups of public health indicators
Physical development indicators
Demography indicators
Morbidity indicators
3
Terminology and definitions 4
Demography as a science studies: 1. The fundamental changes of the size and structure of
populations according to the demographic processes (Formal demography); Formal demography limits its
object of study to the measurement of populations processes.
2. The changes resulting from the influence of natural and social phenomena (Social demography).
broader field of Social demography studies the
relationships between economic, social, cultural and biological processes influencing a population.
Demography AND STATISTICS 5
Demography is a quantitative study of human populations. Demographers study subjects such as the geographical distribution of people, birth and death rates, socioeconomic status, and age and sex distributions in order to identify the influences on population growth, structure, and development.
Demography is the statistical study of all populations. It can be a very general science that can be applied to any kind of dynamic population, that is, one that changes over time or space.
It encompasses the study of the size, structure and distribution of populations, and spatial and/or temporal
changes in them in response to birth, migration, agingand death.
Demography and Public Health Needs
Understanding a society's demography is an essential tool in determining current and future public health needs. Demographic structure can affect public health needs in at least three ways:
(1) age structure and sex ratio affect the types of health problems encountered;
(2) population growth rates affect future needs for health care delivery, and
(3) the existence of substantial immigrant and refugee populations can also be important to plan the volume of care.
6
Basic demographic equation
Suppose that a country (or other entity) contains
Populationt persons at time t. What is the size of the
population at time t + 1 ?
Populationt + 1 = Populationt + Natural increaset +
Netmigrationt
Natural increase from time t to t + 1:
Natural increaset = Birthst − Deathst
Net migration from time t to t + 1:
Net-migrationt = Immigrationt − Emigrationt
7
IMPACTS OF BIRTH and DEATH rate
The health needs of a population differ
considerably by age and by sex.
A population's history of birth and death rates
changes the age structure in a way that is easy to
predict.
Generally, a fertility decline reduces the
proportion of children in a population,
while a decline in death rates increases life
expectancy and the proportion of elderly in the
population.
8
HOW sex ratio can affect health care needs
For most age groups, the sex ratio (that is the ratio of males to
females) is close to equal.
Men have higher death rates than women. As a result, at older
ages sex ratios are generally much lower.
There are many fewer men than women.
Women are likely to have longer life spans than men, they are more
likely to become widows and to have to care for themselves at
older ages.
9
APPLICATION OF DEMO-INDICATORS
Demographic indicators are the basis for:
the planning of resources,
anticipating needs,
deployment strategies and
the evaluation of results. These indicators, while occurring with
some delay in terms of social facts and events, are very sensitive
to medium-and long-term forecasts.
The demographics are interpreted in the context of quality of
life. First of all, these are the years of active life after 65 years of
age.
The general trend towards an ageing population in developed
countries implies increased demand for health care.
10
Methods for the collection of demographic DATA
1. Direct:
Direct data come from vital statistics registries that track all births and deaths as well as certain changes in legal status such as marriage, divorce, and migration (registration of place of residence).
Censuses: Usually within 10 years’ period entries of households data.
2. Indirect:
Studying the trends in life expectancy and the growth of the population using research methods and mathematical models.
- Representative sample of the population is interviewed about their reproductive attitudes .
-Predictions about further state of the population are based on calculations using matrices ,,life tables,, etc.
11
Indirect methods of data collections12
Required in countries where full data are not available, such as is the case in much of the developing world.
One of these techniques is the “sister method”, where survey researchers ask women how many of their sisters have died or had children and at what age.
With these surveys, researchers can then indirectly estimate birth or death rates for the entire population.
Other indirect methods include asking people about siblings, parents, and children.
Demographic methods for modeling population processes. They include models of mortality (including the life table, hazards models, fertility models (Hernes model, Coale-Trussell models, parity progression ratios), marriage (Singulate Mean at Marriage, Page model), disability (Sullivan's method, multistate life tables), population projections.
census 13
A census is usually conducted by a national government and attempts to enumerate every person in a country. However, in contrast to vital statistics data, which are typically collected continuously and summarized on an annual basis, censuses typically occur only every 10 years or so, and thus are not usually the best source of data on births and deaths. Analyses are conducted after a census to estimate how much over or undercounting took place. Censuses do more than just count people. They typically collect information about families or households, as well as about such individual characteristics as age, sex, marital status, literacy/education, employment status and occupation, and geographical location. They may also collect data on migration (or place of birth or of previous residence), language, religion, nationality (or ethnicity or race), and citizenship.In countries in which the vital registration system may be incomplete, the censuses are also used as a direct source of information about fertility and mortality; for example the censuses of the People's Republic of China gather information on births and deaths that occurred in the 18 months immediately preceding the census.
POPULATION CENSUS14
1. Population - number and territorial distribution2. Population structure by sex and age3. Citizenship4. Ethno-demographic characteristics of the population5. Legal and de-facto marital status6. Educational structure of the population7. Economic activity of the population8. Migration of the population9. Housing conditions – type of dwelling, average number of inhabitants,average area10. Housing characteristics and availability of durables
History of censuses in Bulgaria
1880-the Principality of Bulgarian
1887 – Circuit
1892-1900 Homes, farm animals – a special law on the Census
1905 – agricultural equipment and buildings
1910 – transport in agriculture
1920 – Treaty of Neuilly same
1926 – agricultural equipment, craft-industrial enterprises
1934 – educational institutions
1946 – housing
1956 – family representative excerpts 1965-birth rate, excerpts 1975 –lowest territorial level 1985 – register of population, Villa fund
1992 – employment, unemployment, privatization, agrarian reform
2001-Eurostat
2011- Latest census, Bulgaria in the EU
15
Dynamics of the population in Bulgaria
according to censuses 1900-2011
16
Characteristics of human populations17
Characteristics: size, density, age, sex distribution,employment, incomeresidencehealthThe study of human populations:vital statistics: births, marriages, deaths, migration, growth,
DEMO-INDICATORS
1. Indicators for the current state of the population
STATICS
2. Indicators for the development of the population DYNAMICS
Indicators for the reproduction of the population
18
19
Country Populationnumber
millions
Populationas
% of EU
Surface Surface as
% of EU
Density Population/km
2
ЕС 494.8 100% 4,422,773
100% 112
Австрия 8.3 1.7% 83,858 1.9% 99
Белгия 10.5 2.1% 30,510 0.7% 344
България 7.7 1.6% 110,912 2.5% 70
Кипър 0.8 0.2% 9,250 0.2% 84
Чехия 10.3 2.1% 78,866 1.8% 131
Дания 5.4 1.1% 43,094 1.0% 126
Естония 1.4 0.3% 45,226 1.0% 29
Финландия 5.3 1.1% 337,030 7.6% 16
Франция [4]
64.1 13.0% 643,548 14.6% 99
Германия 82.3 16.6% 357,021 8.1% 231
Гърция 11.1 2.2% 131,940 3.0% 84
Унгария 10.1 2.0% 93,030 2.1% 108
Indicators for the current state of the
population STATICS
Number of the population
Mean Annual number of the population
Type of the population (0-14, 15-49, 50 + till 1996.
After 1996 in Bulgaria the distribution is 0-17, 18—64, 65+.
Age and gender distribution
Mean longevity of life.
20
Annual number of the population
The annual number of the Population, for a given year =
Number of the Population of latest census +
Natural growth for the time between (t) +
Net-migration for the same time (t).
The natural growth = births (t) − deaths (t)
Net-migration (t) = Immigration (t)−Emigration (t)
21
AGE GROUPS ACCORDING WHO
According to WHO the following groups are detected:
Young age – up to 44
Middle age – 45- 59
Advanced (aged) – 60 –74
Elderly– 75 – 89
Over 90 .
22
Types of age groups of the
population predicting structure
Type Age groups
0-14 15-49 over 50
progressing 30% 50% 20%
Stationary 25% 50% 25%
Regressing 20% 50% 30%
(till 1996)
23
Structure by age and sex 24
The process of demographic aging continues. It is expressed by reducing the absolute number and relative share of the population younger than 15 years and increasing the share of population aged 65 years and older. The share of population over 65 increased from 16.8% in 2001 to 18.5% in 2011. At the same time in 2001 persons under 15 years are15.3% of the population in the country. In 2011 their share decreases to 13.2%.
The population aged 65 years and more has the biggest relative share in the followingdistricts: Vidin - 25.5%, Montana and Gabrovo - 24%, Lovech - 23.3%, andKyustendil - 22.8%. The share of adult population is lowest in districts Blagoevgrad,Varna and Sofia - capital – 16%.
62.2% of the population in the country is at working age, i.e. 4 576 904 persons.52.5% of them are men and 47.5% - women. The bigger share of the population atworking age lives in the urban areas - 75.8%, and 24.2% - in rural.
Population pyramide STRUCTURE 25
26
27
28
29
30
Life longevity for the period 1935-2009
for the population in Bulgaria
Periods Total Men Women
1935–1939 51.75 50.98 52.56
1956–1957 65.89 64.17 67.65
1960–1963 69.59 67.82 71.35
1969–1971 71.11 68.58 73.86
1974–1976 71.31 68.68 73.91
1978–1980 71.14 68.35 73.55
1984–1986 71.19 68.17 74.44
1989–1991 71.22 68.02 74.66
1993–1995 70.60 67.10 74.90
1995–1998 70.50 67.10 74.30
Periods Total Men Women
1997–1999 71.00 67.60 74.60
1998–2000 71.70 68.15 75.34
1999–2001 71.80 68.50 75.20
2000–2002 71.87 68.54 75.37
2001–2003 72.07 68.68 75.59
2003–2005 72.60 69.00 76.30
2004–2006 72.60 69.10 76.30
2005–2007 72.70 69.20 76.30
2006–2008 73.00 69.50 76.60
2007-2009 73.43 69.90 77.08
Source: National Health Institute
31
RURAL/ URBAN POPULATION
DIstribution
The tendency of increase the relative share of
urban population and decrease of the rural
population is kept: 5 339 001 persons, or 72.5% live
in urban areas
and 2 025 569 persons, or 27.5 % - in rural areas.
32
Urban/Rural population distribution 33
1946 1956 1960 1970 1980 1990 2000 2005 2006 2007 2008 2009
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
фиг 2: Разпределение по градове и села
селско
градско
години
пр
оц
ен
т
Distribution by number and sex in Bg34
years total men women
1990 8 669 269 4 269 998 4 399 271 – 50,70%
1995 8 384 715 4 103 368 4 281 347 – 51,06%
2001 7 891 095 3 841 163 4 049 932 – 51,32%
2005 7 718 750 3 743 327 3 975 423 – 51,50%
2006 7 679 290 3 720 932 3 958 358 – 51,56%
2007 7 640 238 3 699 689 3 940 549 - 51.60%.
As on 31.12. 2007 women are more than men (51.6%).
Compared to 1990 there are 570 309 men and 458 722 women
left the country or died.
WORKING AGE TRENDS
The ageing of population leads to change in its main age structure –distribution of
population under, at and over working age. Influence on the share of population at and over
working age has the ageing of population, as well as the legislative changes in determining the
retirement age.
62.2% of the country population is at working age or 4 576 904 persons. 52.5%
are male and 47.5% - female. 65% of the urban population is at working age, compared to
54.7% - of rural population.
Sofia is the district with the highest relative
35
Distribution of the population upon
working demo-status
36
Years Total
Age groups
Younger
groups - %
Working
age - %Retired - %
1990 100 21.6 55.5 22.9
1995 100 19.1 56.6 24.3
2001 100 16.3 59.2 24.5
2005 100 14.8 62.4 22.8
2006 100 14.6 62.8 22.6
2007 100 14.5 63.0 22.5
Working age
Trends:
37
demographic replacement rate
38
The reproduction of population at working age is best characterized by the demographic replacement rate.
It represents the ratio between the number of personsentering working age (15 - 19 years) and persons exiting the working age (60 – 64 years).
Totally, for the country, the ratio is 70. For comparison, in 2001 every 100 persons exiting the working age are replaced by 124 young people.
Population development
Nativity
Mortality
Natural growth
Number of life born during the year
Nativity=-------------------------------------- 1000.
average annual number of the population
Mortality is defined similarly.
39
Indicators for development of the
population DYNAMICS
(1) Mortality rate because of…
War victims total number: 337 000
92 years later: vehicle accidents 30-40 000
(2)Mobility/ migrationFor a total of 100 year 410 000 emigrants
For 89-92 year 470 000 emigrants
40
NATIVITY, MORTALITY and NATURAL GROWTH (total)
41
Number per1 000 people
Year Live born Dead. Nat. gr. Live born Dead Nat. gr.
.
1970 138745 77095 61650 16.3 9.1 7.2
1980 128190 97950 30240 14.5 11.1 3.4
1990 105180 108608 -3428 12.1 12.5 -0.4
1995 71967 114670 -42703 8.6 13.6 -5.0
2000 73679 115087 -41408 9.0 14.1 -5.1
2005 71075 113374 -42299 9.2 14.6 -5.4
2007 75349 113004 -37655 9.8 14.8 -5.0
2008 77712 110523 -32811 10.2 14.5 -4.3
2009 80956 108068 -27112 10.7 14.2 -3.5
Source: National Statistical Institute
Nativity, mortality and natural growth per 1000 people in Bulgaria for the period 1945 - 2007
42
Раждаемост, смъртност и естествен прираст на 1000 души
от населението за периода 1945 - 2007 година
Total child mortality and child mortality rate
years number
total urban rural
1970 3788 1811 1977
1980 2594 1560 1034
1990 1554 1020 534
1995 1065 705 360
1997 1123 719 404
2000 981 657 324
2005 739 464 275
2006 720 472 248
2007 690 447 243
2008 668 444 224
2009 729 468 261
Years 1 000 live born
total urban rural
1970 27.3 22.7 33.5
1980 20.2 18.0 24.9
1990 14.8 13.8 17.1
1995 14.8 14.0 16.7
1997 17.5 15.7 22.0
2000 13.3 12.4 15.5
2005 10.4 8.9 14.6
2006 9.7 8.6 13.1
2007 9.2 7.9 12.7
2008 8.6 7.6 11.6
2009 9.0 7.7 12.9
43
Total and child mortality rate trend 44
200745
Total mortality rate: 14.8
Child mortality rate: 9. 2
Premature deaths rate: 24.1
46Structure of internal migration 2007 (%)
Directions:
village to city-22%
Village to village -11%
City to city 38%
City tо village – 29%
LEADING GLOBAL DEMO-TRENDS
1. Demo-transition
2. Earth population growth
3. ЕС population demography
4. Bulgarian population demography
47
Demo-transition In the most highly developed
countries, the trend to increase
the number of the population
tends to zero. And this is not
caused by starvation or lack of
resources. The cause was
birth control in these countries.
Despite the extension of the life
longevity in these countries the
number of population stagnates
or dicreases. The model follows
periods of: 1. low or zero growth
in the pre- industrial societies, 2.
rapid population growth during
industrialization 3. reduction of
growth when it raised the
standard of living – this is the
demographic transition.
48
Academicians estimates, actual, high, medium, low rate
Earth population growth
From the beginning of the censuses to 1650 population growth is
extremely slow – barely 0.06%.
The population in Europe and North America and in other parts of the
world grew the fastest between 1920 and 1960.
From 1650 to the end of the 20th century the growth of the
population of the Earth is nearly 12 times.
49
NUMBER OF THE WORLD POPULATION
AND REPRODUCTION RATE (1650-2050)
50
GLOBAL TRENDS IN WORLD DEMO51
52
immigration and emigration
Factors for: Improvements in transportation and changing political
and economic circumstances;
Immigrants groups:
refugees, who are those fleeing their home countries because of
political persecution or war;
and labor or economic migrants, who go to other countries seeking
employment and a better life.
Refugees and economic migrants can move between two
countries or within a single country.
53
POPULATION GROWTH IN 20th Century
World population grew at a more rapid and sustained pace
than at any time in human history.
The global population grew from approximately 1.7 billion
people in 1900 to 6 billion in 1999.
The annual population growth rate averaged 1.3 percent for
the entire twentieth century, and was as high as 2.3 percent
between 1965 and 1970.
(A sustained 2.3 percent annual growth rate would have
meant a doubling of the world's population in thirty years.)
54
mortality decline in Europe and North
America FACTORS
Improvements in public health (including sanitation, waste disposal,
clean water supply, and quarantine); changes in personal hygiene
(including bathing, handwashing, and household cleanliness);
Improved standards of living (including better nutrition and housing);
Improved political, economic, and transportation systems, which led
to better responses to food shortages and drought.
55
PROCESSES OF CHANGING THE POPULATION
fertility,
mortality,
and migration.
Fertility involves the number of children that women
have and is to be contrasted with fecundity (a
woman's childbearing potential
56
Reproduction coefficients AND
REPRODUCTIVE ATTITUDES OF WOMEN
An indicator of the total fertility rate (total fertility rate)-demonstrates how many children a woman gives birth during her fertility period (15 – 49).
Gross reproduction rate-demonstrates how much is the average number of girls whom gave birth a woman throughout the fertile period (it is estimated that the number of births of girls is essential).
Net reproduction rate-demonstrates the average number of live born girls by a woman throughout the fertile period of woman; It is calculated, taking into account and mortality of women during the same period .
The decline in birthrates is due to dramatic changes in economic and social conditions, ideas about the family and the role of children and women, the availability of family planning programs, and the acceptance and use of contraception.
57
birth rate
The crude birth rate, the annual number of live
births per 1000 people.
The general fertility rate, the annual number of live
births per 1000 women of childbearing age (often
taken to be from 15 to 49 years old, but
sometimes from 15 to 44).
age-specific fertility rates, the annual number of
live births per 1000 women in particular age
groups (usually age 15-19, 20-24 etc.)
58
mortality rate
The crude death rate, the annual number of
deaths per 1000 people.
The infant mortality rate, the annual number of
deaths of children less than 1 year old per 1000
live births.
The expectation of life (or life expectancy), the
number of years which an individual at a given
age could expect to live at present mortality
levels.
59
60
Income inequality and mortality rate 60
FERTILITY INDICATORS
The total fertility rate: the number of live births per
woman completing her reproductive life (15-49), if
her childbearing at each age reflected current
age-specific fertility rates.
The gross reproduction rate: the number of
daughters who would be born to a woman
completing her reproductive life at current age-
specific fertility rates.
The net reproduction ratio is the expected number
of daughters, per newborn prospective mother,
who may or may not survive to and through the
ages of childbearing.
61
Reproduction of World
population for the year 2000
Nativity Mortality Fertility Longevity
Total: 22.1 8.9 2.7 65.4
Africa: 38.0 13.9 1.0 51.4
Asia: 21.9 7.7 2.6 66.3
Europe: 10.3 11.3 1.4 83.3
S Americ: 23.1 6.5 2.7 69.2
N Americ: 13.8 8.3 1.9 76.9
Oceania: 17.9 7.7 2.4 73.8
USA: 14.0 8.5 2.0 76.7
Bulgaria 9.0 14.1 1,3 65.4
62
63
THANK
YOU
FOR
YOUR
ATTENTION