demography 1
TRANSCRIPT
-
8/13/2019 Demography 1
1/21
Demography 1
Dr Paul T Francis, MD
Prof. Com MedCollege of Medicine, Zawia
-
8/13/2019 Demography 1
2/21
Demography
Demography is the scientific study
of human population
Demography studies 3 aspects of a
population
Changes in population size
Composition of population
Distribution of population in place
-
8/13/2019 Demography 1
3/21
Demographic processes
The demographic processes that
determine the size, composition
and distribution of a population are:
Fertility
Mortality
Marriage
Migration
Social mobility
-
8/13/2019 Demography 1
4/21
Sources of Demographic
information
Population census
Vital statistics
Migration
Before we plan any health interventionor programmes for the community we
should know the size and composition of
the community
We also need to know the changes that
will occur to the size and composition to
the population
-
8/13/2019 Demography 1
5/21
Demographic cycle
Population of all countries go
through the following stages
1ststageHigh stationary
2ndstageEarly expanding
3rdstageLate expanding
4thstageLow stationary
5thstageDeclining
-
8/13/2019 Demography 1
6/21
Demographic cycle
High stationary
There is high birth rate and high death
rate so the population remains
stationary. There is no increase or decrease in
the population
-
8/13/2019 Demography 1
7/21
Demographic cycle
Early expanding
Death rate begins to decline while
birth rate does not change
Many countries in Asia and Africa arein this stage
-
8/13/2019 Demography 1
8/21
Demographic cycle
Late expanding
The death rate declines further and
the birth rate also starts to decline.
Since the death rate is lower than birthrate the population keeps increasing
Some developing countries are in this
stage Libya is in this stage
-
8/13/2019 Demography 1
9/21
Demographic cycle
Low stationary
In this stage the death rate and the
birth rate are both low
So the population becomes stationaryagain
There is no increase or decrease in
the population
-
8/13/2019 Demography 1
10/21
Demographic cycle
Declining
In this stage the birth rate is lower
than the death rate
So the population starts to decline
-
8/13/2019 Demography 1
11/21
-
8/13/2019 Demography 1
12/21
-
8/13/2019 Demography 1
13/21
World population
About th of world population livesin the developing countries
China and India are the two most
populous countries in the worldThe world population growth rate
was at the peak in 1970
About 95% of the population growthis occurring in the developingcountries
-
8/13/2019 Demography 1
14/21
Life expectancy
Life expectancy is the average
number of years which a person of
a particular age may expect to live
It is one of the best indicators of a
countrys level of development andoverall health status
The life expectancy of people allover the world has been increasing
-
8/13/2019 Demography 1
15/21
Life expectancy at birth
In most countries the life
expectancy of women is more than
that of men
Life expectancy in Japan is the
highest 86 79
Life expectancy in USA is 80 76
Life expectancy in Libya is
75 70
-
8/13/2019 Demography 1
16/21
Fertility
FertilityIs the actual bearing ofchildren by a woman
The reproductive age of a woman is
between 1545 yearsSome factors affecting fertility are:
Age at marriage
Duration of married life Spacing of children
Education
Socioeconomic status
-
8/13/2019 Demography 1
17/21
Fertility
Birth rate =
Growth rate =Crude birth rateCrude death rate
Number of live births during the year
Estimated mid-year population
X 1000
-
8/13/2019 Demography 1
18/21
Demographic indicators of Libya
Crude Birth rate (1978) = 47.0
Crude Death rate (1978) = 5.1
Growth rate is 42/1000 = 4.2%
Total fertility rate (per woman) = 2.8
-
8/13/2019 Demography 1
19/21
Population structure of Libya
< 5 = 20.7%
-
8/13/2019 Demography 1
20/21
Summary
Study of population is important for
promoting health of population
The size and composition of the
population will help us plan forhealth interventions
Study of human population will help
us plan for the future health needsof a community.
-
8/13/2019 Demography 1
21/21