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My Own Demography 4 Demographic transition.pptx

  1. Demographic Transition Dr. Farrah Pervaiz MBBS ,MSPH ,PhD Fellow Assistant Professor Dept of Public Health AFPGMI/NUMS I
  2. DTM… The DTM describes a sequence of changes in the relationships between birth and death rates. The model was produced using changes in the natural increase in several countries in Western Europe and North America.
  3. Demographic Transition Model (DTM)
  4. DTM… It explains the transformation of countries from having high birth and death rates to low birth and death rates. In developed countries this transition began in the 18th century and continues today. Less developed countries began the transition later and many are still in earlier stages of the model.
  5. DTM… It suggests that the population growth rates for all countries can be divided into 4 stages.
  6. Stage 1 HighStationary
  7. • Birth Rate • VeryHigh • Death Rate • VeryHigh • Natural Increase • Population Steady
  8. Stage 1 Birth Rate is high bc of: • Lack of family planning • High IMR: putting babies in the 'bank' • Need for workers in agriculture • Religious beliefs • Children as economic assets Death Rate is high bc of: • High levels of disease • Famine • Lack of clean water and sanitation • Lack of health care • War • Competition for food • Lack of education
  9. Stage 2 EarlyExpanding
  10. • Birth Rate – • VeryHigh • Death Rate – • FallingRapidly • Natural Increase – • VeryRapid Increase
  11. Demographic Transition Model (DTM)
  12. Death Rate is falling as a result of: • Improved health care (e.g. Smallpox Vaccine) • Improved Hygiene (Water for drinking boiled) • Improved sanitation • Improved food production and storage • Improved transport for food • Decreased Infant Mortality Rates Stage Two Typical of Britain in 19th century; Nigeria Birth Rate remains high. Death Rate is falling. Population begins to rise steadily.
  13. Stage 2 Kenya
  14. Stage 3 LateExpanding
  15. • Birth Rate: • Fallingrapidly • Death Rate: • Falling moreslowly • Natural Increase: • Rapid increase Stage 3
  16. Demographic Transition Model (DTM)
  17. Reasons behind birth and death rate falling: • Family planning available • Lower Infant Mortality Rate • Increased mechanization reduces need for workers • Increased standard of living • Changing status of women Stage Three Birth Rate starts to fall. Death Rate continues to fall. Population rising
  18. Stage 3
  19. Stage 4 LowStationary
  20. • Birth Rate: • Falling more slowly • Death rate: • Slight fall • Natural Increase: • Very slow increase
  21. Demographic Transition Model (DTM)
  22. Stage 4
  23. Stage 5 DecliningPopulation
  24. • Birth Rate: • Slightfall • Death Rate: • Stable • Natural Increase: • Gentledecrease
  25. Demographic Transition Model (DTM)
  26. Stage Five • Stage 5
  27. 29 Impacts and Consequences of demographic transition Four Stages Impacts 1. Very Low Growth 2. High Growth 3. High but Slowing Growth 4. Low Growth Some now see a fifth stage 5. ??? Decline sets in ???? Factors That Change over the Stages • Family Size • Infant Mortality & Fertility Rates • Family Economics • Status of Kids • Gender Roles • Health Conditions • Transportation Facilities • Child Deaths • Population Size
  30. Demographic Trap –Example Sudan(Failed State?-----Classic Case) It has developed far enough economically and socially to reduce mortality, but not far enough to quickly reduce fertility As a result, women on average have four children, double the two needed for replacement, and the population of 41million is growing by over 2,000 per day Under this pressure, Sudan is breaking down.
  31. • It does not include the influences of migration • It assumes that all countries will go through the same pattern • There is no time scale • Reasons for changing birth rates and death rates are very different in different countries Limitations of DTM
  32. Limitations of the model • The model was developed after studying the experiences of countries in Western Europe and North America. Conditions might be different for LEDCs in different parts of the world. • The original model doesn't take into account the fact that some countries now have a declining population and a 5th stage.
  33. Epidemiologic Transition A characteristic shift in the disease pattern of a population as mortality falls during the demographic transition: acute, infectious diseases are reduced, while chronic, degenerative diseases increase in prominence, causing a gradual shift in the age pattern of mortality from younger to older ages
  34. Demographic/ Epidemiologic Transition Framework
  35. Epidemiologic Transition • Pestilence (infections) & Famines – Infections & Nutritional Deficiencies • Receding Pandemics – Improved sanitation, Dec infections, Inc Diet (salt), inc Aging – Developing Countries • Degenerative & Man made Diseases – Inc aging, Lifestyles related to high SES, (diet, activity, addiction) – Countries in transition • Delayed degenerative & emerging infections – (Hybristics) The term ‘hybris’ refers to excessive self-confidence or a belief of invincibility. During the hybristic stage, morbidity and mortality are affected by man-made diseases, individual behaviours, and potentially destructive lifestyles. – Reduced risk behaviors (Health promotion and prevention) – New treatments – Western countries
  36. Demographic Transition Egeo 312 39 Examples Sweden – Historic Industrial Country Mexico – An Industrializing Country
  37. Demographic Transition Egeo 312 40 Developed Country Example
  38. Demographic Transition Egeo 312 41 Developing Country Example
  39. Demographic Transition Egeo 312 42 Example of how families adjust to lower infant mortality rates with lower fertility Result is a decline in CBR
  40. Demographic Transition Egeo 312 43 Comparison of Development and Wealth to Population Growth Rates across Countries
  41. Demographic Transition Egeo 312 44 Where is the World’s Population Growing? Declining?
  42. Demographic Transition Egeo 312 45 Declining World Mortality Rates Map At the end of the second and the beginning of the third stages of the demographic transition, death rates declined. Where did they first decline and where did they last decline? Created by Ingolf Vogeler on 1 February 1996
  43. Demographic Transition Egeo 312 46 ONE LAST CONCEPT
  44. Demographic Transition Egeo 312 47 Dependency Ratio Ratio of non-working population to working age population Non-Workers are the young and aged retirees – young are usually 15 yrs old and below – retirees are usually 64 yrs old and above
  45. Demographic Transition Egeo 312 48 Pakistan’s High Dependency Ratio now and in the future based on lots of kids but few elderly. However note how the young population is expected to stabilize and elderly grow.
  47. 1. Replacement rate, the number of births needed to keep a population at a stable level without immigration, requires a total fertility of a. 10. b. 2.1. c. 3.5. d. 5. 3. Which of the following countries is most likely to be showing the lowest natural increase rate? a. Afghanistan b. United States c. Japan d. Chile
  48. 4. Countries with aging populations attempt to stimulate economic growth to lessen the effect of rising medical and retirement costs by a. cutting social security. b. encouraging increased birth rate. c. promoting immigration. d. promoting emigration of the elderly.
  49. 5. Demographically, Great Britain experienced a ___________________ in the period from the late 1800s through WWII. a. population decline b. rising death rate c. population explosion d. rapid birth rate decline
  50. 7. The medical revolution has been characterized by a. Development of new inventions b. Diffusion of medical practices c. Increased agricultural productivity d. Invention of new medicines 8. The average number of births women bear in their lifetime is a. total fertility rate b. crude birth rate c. natural increase rate d. crude death rate
  51. 9. A decline in a country’s crude birth rate would result in an increase in the country’s a. Doubling time b. Natural increase rate c. Total fertility rate d. Life expectancy rate 10. The low rate of contraceptive use in Africa reflects the region’s a. low status of women b. Improving education of women c. Rapid diffusion d. A and B
  52. Assignment( SAQs) Explain your answers in relation to demographic transition model. 1. Why is population growing so fast? 2. Which areas are growing fastest? 3. What effects has this growth had on social and ecological systems?