Demography

Demography as the statistical study of human population with regard to their size & structure, their composition by sex, age, marital status and ethnic origin, and the changes to these population, like changes in their birth rates, death rates and immigration.
Demography is the branch of social size, structure, which deals with the study of size, structure and distribution of populations, along with the spatial and temporal changes in them in response to birth, migration, ageing and death.
In demography the following three elements of population are given special attention:
Change in the size of population (increase or decrease)
Structure of population (on the basis of sex or age groups)
Geographical distribution of population (on the basis of state or territory).

1. Demography Presented by: Harsh Rastogi , Nursing Tutor, M.S. Institute of Nursing, Lucknow

2. Introduction Demography  is the statistical study of human populations. Demography  examines the size, structure, and movements of populations over space and time. Demography  is useful for governments and private businesses as a  means  of analyzing and predicting social, cultural, and economic trends related to population.

3. Etymology Demography  (from prefix  demo-  from Ancient Greek  δῆμος ( dēmos ) meaning 'the people', and  - graphy  from γράφω ( graphō ) meaning 'writing, description or measurement') is the statistical study of populations, especially human beings. Demo: people Graphy : description The word was coined by John Graunt in 1662.

4. Cont… John Graunt  (24 April 1620 – 18 April 1674) has been regarded as the founder of demography. Developed early human statistical and census methods that provided a framework for modern demography.

5. Demography Demography as the statistical study of human population with regard to their size & structure, their composition by sex, age, marital status and ethnic origin, and the changes to these population, l ike changes in their birth rates, death rates and immigration. Demography is the branch of social size , structure , which deals with the study of size, structure and distribution of populations, along with the spatial and temporal changes in them in response to birth, migration, ageing and death.

6. Definitions Demography is the ‘ study of human populations in relation to the changes brought about by the interplay of births, deaths, and migration .’ Demography is the ‘ scientific study of human population in which includes study of changes in population size , composition and its distribution .’

7. Cont… Demography is the ‘ statistical and mathematical study of the size, composition and spatial distribution of human populations, and of the changes over time, in these aspects through the operation of the five processes of: fertility , mortality , marriage , migration and social mobility .’ D em o gr a p h y is t h e stat i st i ca l description and analysis of human population .

8. Concept Demography is a branch of science which studies the human population. In demography the following three elements of population are given special attention: Change in the size of population (increase or decrease) Structure of population (on the basis of sex or age groups) Geographical distribution of population (on the basis of state or territory).

9. Cont… Some commonly used concepts are: Stillbirth Foetal death Family size Child death Live birth Parity Adulthood

10. Cont… Contraception Sterility Birth order Marriage Reproductive span Separation and divorce Fertility Fecundity Cohort

11. Cont… Ratio Migration Proportion Rates Percent Natural increase and rate of natural increase

12. Scope of demography It is very important for community health nurse to know demographic aspects of their community. Information regarding population static: It will help the nurses to plan and manage need based health care services for the community at large. It includes: Total population Age and sex composition Median age and dependency ratio Socioeconomic characteristics

13. Cont… Family size Life expectancy Distribution and concentration Information regarding population Crude mortality rate Specific mortality rate Age specific mortality rate dynamics

14. Cont… Total population: This will help to determine the bulk of services and the work load which health workers are going to have: Age and sex composition: This will help to analyze health needs, morbidity, and mortality pattern utilization of health care services and accordingly plan and manage health care services.

15. Cont… Median age and dependency ratio : This will help to know about the ratio of young and elderly population and adult population. This will help nurses to determine economic burden.

16. Cont… Socioeconomic characteristics : These characteristics include education, marital status occupation, income, etc. This will help not only to identify socioeconomic status but also morbidity and mortality pattern and fertility behaviour.

17. Cont… Life expectancy: Information regarding life expectancy will help her to understand and appreciate the impact of health care services on morbidity and mortality among people.

18. Cont… Distribution and concentration: Distribution and concentration of population in the community will help to identify areas where services are needed most.

19. Cont… Information regarding population dynamics: It will help nurses to understand the changes that are taking place in the population under the influence of fertility, mortality, and migration pattern in community.

20. Cont… Crude mortality rate, birth rate: These rates will help nurses to know natural increase in population and compute growth rate.

21. Cont… Specific mortality rates: These include age, sex, cause specific rates, case fatality, and proportional mortality rate.

22. Demographic Cycle Stage: High Stationary Stage: Early Expanding Stage: Late Expanding Stage: Low Stationary Stage: Declining

23. Cont… High stationary (First Stage ): This stage is characterized by a high birth rate and high death rate, population remains stationary . India was in this stage till 1920. Early expending (Second Stage ) : The death rate begins to decline while the birth rate unchanged initial increase in population South Asia & Africa are in this stage.

24. Cont… Late Expanding (Third Stage): The death rate decrease still further and birth rates tends to fall, continue increase in population. Example: China, Singapore, India. Low Stationary (Fourth Stage ): This stage is characterized by a low birth rate & low death rate, stability in population . Example: Australia in 1980-85.

25. Cont… Declining (Fifth Stage ): In the declining stage birth rate is lower then the death rate, fall in population. European, Germany and Hungary countries present facing this stage.

26. Method of data collection Data collection is an important aspect of any type of research study. Inaccurate data collection can impact the results of a study and ultimately lead to invalid results. Primary Data: The data collected directly from individuals by face to face survey is called primary data. It is first hand information. For examples: Data collected during census Data related to health from an individual. Data related to illness from an individual.

27. Primary data Primary data collection is done by an individual by using the methods such as: Interview method Observation Questionnaire Dairies Surveys

28. Interview method Interviews are undertaken on personal, one to one basis or in a group. Interviews can be conducted at work, home as well as any fixed place (location) which was agreed by the both parties. PV Young mentioned that the interview is a systematic method by which a person enters more or less imaginatively into the life of a comparatively stranger.

29. Cont… Interviews are classified into two: Structured interview: In structured interview, the questions are predetermined. The prefixed structured questions which an individual has to answer by ticking off or by short answers.

30. Cont… Unstructured interview : In unstructured interview, the interviewer begins by asking general questions and encourages the person to talk freely. The interviewer probes for elaborations by asking why, tell me more, how, etc. Interviews can be conducted telephonically, which is an alternative form of interviewing the person.

31. Cont… Advantages of interview method: It is the way to collect in-depth information Feedback and respondent rate is good The information is recorded immediately and is complete Help can be provided immediately, if required.

32. Cont… Disadvantages of interview method: It requires more money, It requires more time Training is required in case of many interviewers Investigator must be well-trained Prefixed set of questions are required.

33. Observation method It is a method to record behavioural pattern of people in systematic manner: Observation is one of the basic method of collecting first hand information. Observation method provides information what is actually observed but bias be there. Observation visits can be formal, well planned and objective based. Explain the purpose of making observatory visits.

34. Cont… Observation visits to community can help to gain lot of information about geographical area of the community, environmental sanitation, socioeconomic conditions, observation of home environment, interaction, and communication among family members can get information about family characteristics, health status of members and environmental health, etc. Accordingly observation checklist can be prepared to collect and record information.

35. Questionnaire It can set for large number of people and save researchers time and money: The questionnaire can be used for the purpose of interviewing or telephonic survey. It can be posted, emailed or faxed. The main advantages of this method is that there is no bias The use of questionnaire is simple but it requires a certain level of education and skill from respondents. People are more truthful while responding through paper and pencil.

36. Diaries Diaries are to record the data obtained from the individuals: The data from the people which was expressed in-depth can be recorded and utilized for research purposes.

37. Surveys A survey is a method of gathering information from a sample of people, traditionally with the intention of generalising the results to a larger population. Surveys provide a critical source of data and insights for nearly everyone engaged in the information economy, from businesses and the media to government and academics.

38. Secondary Data Data collected from another source or other sources or outside the source is called Secondary data. For examples: Data taken from hospital records Data taken from census.

39. Secondary data collection is done by using the methods such as: 1. Census 2. National survey 3. Registration of vital events 4. Record review method.

40. Census Census is defined as the simultaneous recording of demographic, social, and economic data of a countries population on a specified day. Census is conducted by national government every 10 years. The first census conducted on 1881 The last census was conducted in Feb-March-2011.

41. Cont… The census is providing information includes age, sex, marital status, language, education, occupation, economic status, place of birth and employment status number of children's, number of death, etc. The Census Commissioner of India is an overall in-charge of conducting census in India. The Census Commissioner of India guides, operates, and directs the census.

42. Registration of vital events It is an important source for getting information about vital events such as births, death, marriages, etc. In this system every important event about population is registered. It is done by varies agencies like panchayath , corporation, municipality, police, hospital, and revenue system. In order to improve the civil registration system, Central Birth and Death Registration Act was passed on 1 April 1969-70 by Government of India.

43. Cont… The Act makes it compulsory for the registration of birth and deaths throughout India. The time limit for registration of birth is 14 days and the time limit for registration of death is within 7 days. In case of failure of doing so, a fine up to 50 will be imposed. In some countries births and deaths are recorded by the first time health workers such as village health guides.

44. National survey Survey conducted at central level to collect the information related to population from various states.

45. Record review method Much of community identification information such as housing conditions, socioeconomic status, demographic information, vital events, health services, etc. are available in the records maintained in health agencies.

46. Analysis of Data The data collected needs to be arranged in tables, charts, diagrams, graphs, pictures and curves to stress important points. The data presented should be based on the principles designed to meet the criteria.

47. Interpretation of Data Interpretation maybe defined as the process of making the sense of the result and examine their implications. The data collected is analyzed and then interpreted. The values interpreted should be in simple way so as to make these understandable. While interpreting, the maximum and minimum values should be should be shown so to have an estimation of in between values. The demographic data can also be analyzed and interpreted by tables, charts, diagrams, pie charts, pictograms, etc.

48. Demographic rates & ratios Population dynamics: Population dynamic refers to the study and measurement of population change and components of change overtime. The population change is influenced by three factors that is: Birth Death Migration This is thus influences the population size, composition, and its distributions.

49. Cont… Measurement Tools for Population Dynamics: Population is not static Population changes with time The changes are due to births, deaths, and migration process Commonly the rate and ratios are tools used to analyze the influences of these process.

50. Rate The large rates are calculated from total number of events which occur in a defined geographical area during a calendar year. The rate can be: Crude Rate Specific Rate Birth & Fertility Rate Death Rate

51. Crude Rate It is based on midyear population. Crude Rate = (Number of total events in an area during the year/Estimated midyear population of the same area during the same year) × 1000.

52. Specific Rate It is based on the specified population by age, sex, etc. Specific Rat e = (Number of total events in specified population an area during the year/Estimated midyear specified population of the same area during the same year) * 1000.

53. Birth and fertility rates The number of babies born in a particular group of people during a particular period of time. The fertility rate at a given age is the number of children born alive to women of that age during the year as a proportion of the average annual population of women of the same age.

54. Crude Birth Rate (CBR) CBR = (Number of live births/Estimated midyear population) * 1000.

55. Fertility rate The fertility rates are completed on the bases of women population in reproductive age, i.e. 15-45/49 years.

56. General Fertility Rate (GFR) GFR = (Number of live births/Women aged 15-45 years) * 1000.

57. General Marital Fertility Rate (GMFR) GMFR = (Number of live births/Married women aged 15-45 in a year) * 1000.

58. Age Specific Fertility Rate (ASFR) The calculation of ASFR for every age group of five year interval during the reproductive age group. ASFR = (Number of live births/Women in any specified age group during the reproductive period) * 1000.

59. Age specific marital fertility rate (ASMFR) ASMFR = (Number of live births/Number of married women in specified age group in a year) * 1000.

60. Total Fertility Rate (TFR) It refers to the average number of children that would be born alive to women if she experiences through all her child bearing years conforming to the age specific fertility rates currently prevalent in community.

61. Death rates and ratios Mortality rate , or  death rate , is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time.

62. Cont… Mortality rate is typically expressed in units of deaths per 1,000 individuals per year; thus, a mortality rate of 9.5 (out of 1,000) in a population of 1,000 would mean 9.5 deaths per year in that entire population, or 0.95% out of the total. Crude Death Rate Specific Death Rate

63. Crude Death Rate (CDR) CDR = (Number of deaths/Midyear population in a year in defined area) * 1000.

64. Specific death rate The cause- specific mortality rate  is the  mortality rate  from a specified cause for a population. The numerator is the number of  deaths  attributed to a  specific  cause. The denominator remains the size of the population at the midpoint of the time period. The fraction is usually expressed per 100,000 population.

65. Age Specific Death Rates ASDR = (Number of deaths in a particular age group/Number of deaths in a mid-year population of that age group) * 1000.

66. Sex Specific Mortality Rate SSMR = (Number of deaths by particular sex/Midyear population of particular sex) * 1000.

67. Age Sex Specific Mortality Rate ASSMR = (Number of deaths by particular age and sex/Midyear population of the same age and sex) * 1000.

68. Other Variables In addition to age and sex specific death rates, there can be many other variables such as occupation, income, religion, etc.

69. Cause Specific Death Rate CSDR = (Number of deaths due to particular disease/Midyear population) * 1000.

70. Maternal Mortality Rate It refers to number of deaths of pregnant women due to any pregnancy related cause within 42 days of termination of pregnancy per 1000 live births.

71. Case Fatality Rate CFR = ( Total number of deaths due to disease/Total number of cases due to same disease) * 1000.

72. Ratio The ratio manifests the relative size of the quantities of two variable: For example, The relative number of females to males, Doctor-nurse ratio. Ratio is result of dividing quantity of one variable with the quantity of another variable. Pregnancy Ratio Abortion Ratio Child Woman Ratio

73. Pregnancy ratio Number of pregnancies in a year: Married women in reproductive age. The number of pregnancies means all the pregnancies. (Live births, stillbirths abortions, and present pregnancy).

74. Abortion ratio Number of all types of abortion: Number of live births. All types of abortions means the abortions which have occurred either as threatened inevitable or abortions due to medical reasons.

75. Child woman ratio Number of children 0-4 years of age: Women of child bearing age, i.e . 15-44 years.

76. Migration It refers to spatial or geographical movement of population involving a change of usual residence between clearly defined geographical units. Demographers distinguish the international and internal migration as follows: International Migration Internal Migration Immigration Rate Emigration Rate Net Migration Rate

77. International migration It refers to movement of people involving permanent change of residence from one country to another. It is designated as emigrants from the nation left and as immigration to the receiving nation.

78. Internal migration It refers to movement of people involving change residence from one area to other within a country.

79. Immigration rate IR = (Number of immigrants in a year/Total midyear population of destination) * 1000.

80. Emigration rate ER = (Number of Emigrants in a year/Total midyear population of area of origin) * 1000.

81. Net migration rate NMR = ((Number of immigrant-Number of Emigrants)/Total midyear population) * 1000.