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CHP400: Community Health Program - lI. kjbkbkljbklb. Mohamed M. B. Alnoor. D E M O G R A P H Y. Objectives. The student will be will be able to: Know the elements of demography Understand the importance of the population nnnn pyramids
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CHP400: Community Health Program - lI kjbkbkljbklb Mohamed M. B. Alnoor
D E M O G R A P H Y Objectives The student will be will be able to: Know the elements of demography Understand the importance of the population nnnn pyramids List factors affecting Population Dynamics Define and Calculate Fertility rates Define and calculate Mortality Rates Define and mention types of migration
D E M O G R A P H Y Definition • Demography is the science that studies human population. • Demography: The study of populations, especially with reference to size and density, fertility, mortality, growth, age distribution, migration, and vital statistics, and the interaction of all these with social and economic conditions. (Oxford Dictionary)
D E M O G R A P H Y Elements of Demography: Three main elements of demography:1- Size of population (census) 2- Composition 3- Distribution
D E M O G R A P H Y Elements of Demography: Size of population Number of all persons in the community. • Census • Estimated population
D E M O G R A P H Y Elements of Demography: Census A process of enumeration of all persons in the community. • Time: 10 Years • Procedures: Enumeration • Demographic • Socioeconomic • Inter-census years: Estimation
D E M O G R A P H Y Elements of Demography: Types Census 1- De Jure Counting individuals at their legal residence regardless of their physical presence. • Factual • Expensive
D E M O G R A P H Y Elements of Demography: Census Types 2- De Facto Counting individuals wherever they actually are on day of census. regardless of their physical presence. • Easier • Economic
D E M O G R A P H Y Elements of Demography: Methods Estimation 1- Natural increase (Number of live births – Number of deaths) added to last census population. (No migration in or out.)
D E M O G R A P H Y Elements of Demography: Methods Estimation 2- Arithmetic mean Two consecutive censuses Mean annual increase Example: 1410: 30000, 1420: 40000 Annualincrease = 10000/10 =1000 1429 40000 + (9 X 1000) = 49000
D E M O G R A P H Y Elements of Demography: Methods Estimation 3- Geometric method Most accurate Special equation (compound interest formula)
D E M O G R A P H Y Elements of Demography: Methods Estimation 3- Geometric method Compound Interest Formula P = principal amount (the initial amount you borrow or deposit) r = annual rate of interest (as a decimal) t = number of years the amount is deposited or borrowed for. A = amount of money accumulated after n years, including interest. n= number of times the interest is compounded per year Methods Methods
D E M O G R A P H Y Last Saudi Census data Population (total) 27,163,977Saudi 18.707.576 Males 9,527,173 (50.9%)Females 9,180,403 (49.1%)Non-Saudi 8,429,401 Males 5,932,974 (70.4%) Females 2,496,427 (29.6%) (2010/1431)
D E M O G R A P H Y Saudi Population Pyramid ( 2006) THE AGE-SEX COMPOSTION OF POPULATIONS
D E M O G R A P H Y Population Pyramid THE AGE-SEX COMPOSTION OF POPULATIONS The importance of the population pyramids Population pyramid is the graphical presentation of the age and sex composition of a population of an area or country at a point in time. The shape of the pyramid reflects the major influences of births and deaths, in addition to any changes due to migration.
D E M O G R A P H Y Population Pyramid THE AGE-SEX COMPOSTION OF POPULATIONS The importance of the population pyramids • Sex • Males are shown on the left side of the pyramid • Females on the right • Age • young persons at the bottom, and • the elderly at the top. • The pyramid consists of a series of bars, each drawn proportionately to represent the percentage contribution of each age - sex group • (often in five-year groupings) to the total population • The total area of the bars represents 100 per cent of the population.
D E M O G R A P H Y Population Pyramid THE AGE-SEX COMPOSTION OF POPULATIONS The importance of the population pyramids • Sex ratio: Percentage of males and females. • Age structure: • Base denotes births (broad or narrow base) • Apex denotes elderly • Mortality and emigration: Shape of sides(sloping or steep). • Life expectancy: (Average number of years that a newborn is expected to live if current mortality rates continue to apply) Height of the pyramid and shape of the apex.
D E M O G R A P H Y Population Pyramid THE AGE-SEX COMPOSTION OF POPULATIONS The importance of the population pyramids • Median Age: (lower or higher) The point in the vertical axis of age through which passes the horizontal line that divides the surface area of the pyramid into two equal parts (50%) younger and 50% older). The position of this defined point is inversely related to the width of the base. The wider the base, (i.e. the higher the birth rate), the lower the median age and vice versa.
D E M O G R A P H Y Population Pyramid THE AGE-SEX COMPOSTION OF POPULATIONS The importance of the population pyramids 6. Dependency Ratio • The dependency ratio describes the relation between the potentially self-supporting portion of the population and • the dependent portions at the extreme of age (below 15 and above 65).
D E M O G R A P H Y Population Pyramid THE AGE-SEX COMPOSTION OF POPULATIONS The importance of the population pyramids Types of Dependency Ratio • Young dependency: Proportion of population below 15 years of age. • Old dependency: Proportion of population above 65 years of age. • Total dependency: Proportion of population below 15 years of age plus the proportion of population above 65 years of age.
D E M O G R A P H Y Population Pyramid Population 15 – 64years The importance of the population pyramids Types of Dependency Ratio Population below 15 years Young dependency ratio X 100 = Population above 65 years X 100 Old dependency ratio = Population 15 – 64years Total dependency ratio Population below 15 years + those above 65 years = X 100 Population 15 – 64years
D E M O G R A P H Y Population Pyramid The importance of the population pyramids How can you calculate the dependency ratio. Use the figures below to calculate the dependency ratio for Britain in 1990. • 0 - 14 = 11.052 million • 15 - 64 = 37.690 million • 65 + = 9.156 million • Young dep=0.29 • Old dep=0.24 • Total dep=0.53
D E M O G R A P H Y Population Pyramid The importance of the population pyramids Use the figures below to calculate the dependency ratio for Egypt in 1990. • 0 - 14 = 22.04 million • 15 - 64 = 32.66 million • 65 + = 1.99 million • Young dep=0.67 • Old dep=0.06 • Total dep=0.73
D E M O G R A P H Y Population Dynamics Objectives By the end of this lecture you will be able to: • List factors affecting Population Dynamics • Define and Calculate Fertility rates • Define and calculate Mortality Rates • Define and mention types of migration
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics • Fertility (births), • Mortality (deaths) • Migration.
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) • Crude Birth Rate (CBR) • General Fertility Rate (GFR) • Age Specific Fertility Rate • Total Fertility Rate (TFR) • Gross Reproduction Rate (GRR)
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) Crude Birth Rate (CBR) Is the simplest indicator of fertility. It is defined as: the number of live births per 1000 mid-year population in a given year and locality. CBR= Total number of live births in a certain year and locality X 1000 Estimated midyear population ( same year and locality)
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) In a certain Country in Year 2000, live births: 325,000; population: 13,000,000 Crude Birth Rate (CBR) Example CBR= Total number of live births in a certain year and locality X 1000 Estimated midyear population ( same year and locality) =… Live Births/ 1000 population in a year. Crude birth rate= 325,000/13,000,000 x 1000 = 25 live births per 1000 population per year
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) General Fertility Rate (GFR) The number of live births in a calendar year, divided by the number of women in the child bearing ages 15-49 at mid year, multiplied by 1000 GFR= Total number of live births in a certain year and locality X 1000 Midyear reproductive female population( aged 15 - 49) = …Live birth/1000 female population aged 15-49.
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) In a certain Country in Year 2000, Number of live births: 325,000; Number of women 15 – 49 : 2,600,000 General Fertility Rate (GFR) Example Calculate GFR GFR= Total number of live births in a certain year and locality X 1000 Midyear reproductive female population(aged 15 - 49) General fertility rate= 325,000 /2,600,000 x 1000 = 125 live births per 1000 women ages 15-49 per year
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) Age Specific Fertility Rate Total number of live births born by females in a specific age group in a certain year and locality X 1000 = Female population in the same specific age group = …Live births/1000 female population in specified age group.
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) • It is the age-specific fertility rate for women aged 15-19. • The annual number of births to women aged 15-19 years per 1,000 women in that age group. Age Specific Fertility Rate Adolescent fertility rate Total number of live births born by females (15-19) age group in a certain year and locality X 1000 = Female population in the (15-19) age group = …Live births/1000 females in 15-19 age group. Calculation of ASFR is important because early pregnancy is related to higher risks of maternal and infant mortality
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) • TFR represents the average number of births that would be born to a woman throughout her reproductive period. • It is expressed as children per woman. • In Saudi Arabia, Total fertility rate (per woman) 3.5 (2006) • In developing countries the TFR is over 6.0 children per woman. • In most developed countries the TFR is under 2.0. Total Fertility Rate (TFR)
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Fertility (Natality Rates) • GRR represents the average number of female births that would be born to a woman throughout her reproductive period. • It is expressed as daughters per woman. • It predicts the fertility of the next generation Gross Reproduction Rate (GRR)
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates A mortality rate is a measure of the frequency of occurrence of death in a defined population during a specified period of time.
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates Crude Death Rate (CDR) The crude death rate is the mortality rate from all causes of death for an entire population = … Deaths/1000 individual in the specified year and locality.
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates In a certain Country in Year 2000, Total population: 13,000,000; Deaths: 65,000 Crude Death Rate = 65,000/13,000,000 x 1000 = 5 deaths per 1000 per year Crude Death Rate (CDR) Example
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates • An age-specific mortality rate is a mortality rate limited to a particular age group. • The numerator is the number of deaths in that age group • The denominator is the number of persons in that age group in the population. • Examples of age-specific mortality rates are infant, neonatal, post-neonatal and under 5-years mortality rates. Age-specific Mortality Rates
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates In a certain Country in Year 2000, For age group: 25-34 yrs: population = 5,000,000; and deaths = 20,000 within same age group Age-specific death rate= 20,000/5,000,000 x 1000 = 4 deaths per 1000 population per year for age group 25-34 Age-specific Mortality Rates Example
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates Infant mortality rate is the probability of a child born in a specific year or period dying before reaching the age of one Age-specific Mortality Rates Infant Mortality Rate (per 1 000 live births) In Saudi Arabia (2006) • Both sexes 21.0 • Females 20.0 • Males 22.0 Total number of deaths from zero up to less than one year during a year in a given locality Infant Mortality Rate = X 1000 Total number of live births in the same year and locality
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates In a certain Country in Year 2000, Number of live births: 325,000; infant deaths: 2,750 Infant Mortality Rate = 2,750/325,000 x 1000 = 8.5 infant deaths per 1000 live births per year Age-specific Mortality Rates Infant Mortality Rate
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates Age-specific Mortality Rates Infant Mortality Rate Infant deaths per 1000 live births
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates The number of deaths of neonates (infants <28 days of age) in a calendar year, divided by number of live births in that year, multiplied by 1000. In Saudi Arabia (2004): • Neonatal Mortality Rate =11 /1000 live births Age-specific Mortality Rates Neonatal Mortality Rate (per 1 000 live births) Total number of deaths from zero up to less than 28 days during a year in a given locality Neonatal Mortality Rate = X 1000 Total number of live births in the same year and locality
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates In a certain Country in Year 2000, Number of deaths at <28 days:2,250; number of live births: 325,000 Calculate Neonatal mortality rate? Neonatal mortality rate= 2,250/325,000x1000 = 6.9 neonatal deaths per 1000 live births Age-specific Mortality Rates Neonatal Mortality Rate
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates Age-specific Mortality Rates Neonatal Mortality Rate Causes of Neonatal mortality • Birth defects (leading cause ) • Prematurity / low birth weight (LBW) (the second leading) • Sudden infant death syndrome. • Maternal pregnancy complications. • Respiratory distress syndrome
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates Age-specific Mortality Rates Post - neonatal Mortality Rate (per 1 000 live births) Post-neonatal mortality rate is the number of deaths among infants from 28 days up to 1 year of age during a given time period divided by the number of live births during the same time period multiplied by 1,000 Total number of deaths from 28 days up to less than one year during a year in a given locality Post - neonatal Mortality Rate = X 1000 Total number of live births in the same year and locality
D E M O G R A P H Y Population Dynamics Factors affecting population Dynamics Mortality Rates Age-specific Mortality Rates Early Late Neonatal Neonatal Neonatal Post-Neonatal 28 day 1year Birth (0 day) I n f a n c y