Data on births and deaths in Africa

1
Population censuses and sample surveys as a
source of fertility statistics
2
Methods used for fertility statistics
Birth histories
Reverse survival
Fertility statistics
The own-child
Recent births
Birth history reconstruction
Children ever born
3
Reverse survival the rational

• Number of births in the population during the
  year prior to the census population under 1
  year of age in the census reverse survival
  factor
• Reverse survival adjustment for mortality
  (persons died before the census was taken)
• If no complete civil registration data, reverse
  survival can be used to estimate the following
  for 15 years prior to census (some surveys)
• Number of births
• Crude birth rates
• General fertility rates
• Assumption No migration! (or can be neglected)

4
Reverse survival - Information needed

• Age by single years
• Better if collected as date of birth
• Level of mortality, can be obtained from
• Children ever-born and surviving (for estimated
  life tables)
• Total number of persons in a year (for crude
  birth rate)
• Number of reproductive age women (general
  fertility rate)

5
Reverse survival - Estimation

• Total number of births x years before the census
  population x year of age in the census
  reverse survival factor

6
Reverse survival - tabulation

• Population by single years of age

7
Reverse survival - quality

• The quality of reverse survival estimates of
  births and birth rates depends on the accuracy of
• Age distribution (most important)
• Reverse survival factors
• Extend of migration (may be important to small
  areas)
• Assessment of quality compare estimates from
  different sources at different times

8
The own-children method the rational

• Match the children reverse-survived with their
  mother ? disaggregate reverse-survived births by
  age and/or other characteristics of mother
• Any person under age 15 ? child
• Note biological children only

9
The own-children method - information needed

• Age, by single years
• Is mother of the child alive and living in the
  same household?
• If yes, which person is the mother?
• Line number of the mother (for this child)
• OR
• Relation to head of household (applies for
  nuclear households or similar types)

10
The own-children method - tabulation
Age of mother Age of child Age of child Age of child Age of child Age of child
Age of mother 0 1 13 14
15
16

63
64
Non-own children
11
The own-children method - estimation

• Age specific birth rate 10-15 years preceding a
  census or survey

12
The own-children method - quality

• The quality of own-children estimates of
  age-specific fertility rates depends on the
  accuracy of
• The quality of matching!
• Age distribution (more important if age
  exaggeration)
• Reverse survival factors
• Extend of migration (may be important to small
  areas)

13
Birth history reconstruction the rational

• Own-children methods
• If number of own-children number of children
  ever-born ? birth history
• If number of own-children lt number of children
  ever-born ? some children live elsewhere or died
• Birth history reconstruction
• Imputes years of births for surviving children
  living elsewhere and deceased children

14
Birth history reconstruction- information needed

• Age, by single years
• Identify mother (line number or relation to the
  household head)
• Number of children ever born
• Number of surviving children

15
Birth history reconstruction- Tabulation
(age-parity)
Year of birth of first child (years prior to census) Year of birth of first child (years prior to census) Year of birth of first child (years prior to census) Year of birth of first child (years prior to census) Year of birth of first child (years prior to census) Age of women at end of year of first birth
55 54 2 1 Age of women at end of year of first birth
0
1

10
11

63
64
16
Birth history reconstruction- Tabulation
(parity-duration)
Year of second child (years prior to census) Year of second child (years prior to census) Year of second child (years prior to census) Year of second child (years prior to census) Year of second child (years prior to census) Completed years in parity 1 at end of year of second birth
21 20 2 1 Completed years in parity 1 at end of year of second birth
0
1

19
20
17
Birth history reconstruction-estimation

• Age-parity-specific birth rates (all women at
  certain age)
• Birth rates specific for parity and duration in
  parity

18
Birth history reconstruction- quality

• Additional quality concerns
• Imputation of dates of birth for non-own and
  deceased children
• If level of mortality is low and most children
  under age 15 lives in the same household as their
  mother, the influence of imputation is minimum.

19
Children ever born some background

• Widely used for over 50 years (although still a
  lot of problems)
• Important for countries do not have complete
  birth registration
• Also important for countries with complete birth
  registration
• Provide fertility measures on birth order and
  parity of women
• Study fertility by socio-economic characteristics

20
Children ever born- information needed

• How many children has this woman had in her
  lifetime?
• incl. all live births
• Could be elaborated into a number of questions
• Asked to all women
• Sex of the child ? sex ratio at birth

21
Children ever born- tabulation
Age of women Number of children ever born Number of children ever born Number of children ever born Number of children ever born Number of children ever born CEB not stated Total women Total children born
Age of women 0 1 14 15 CEB not stated Total women Total children born
10-14
15-19

80-84
85
NS
Total
22
Children ever born- tabulation

• A few important issues
• Do not group the numbers of children, except the
  last open category
• Distinguish children ever born not stated from no
  children

23
Children ever born- estimation

• Parity distribution
• Parity progression ratios
• Average number of children ever born
• Completed fertility
• Total fertility rates
• Age-specific birth rates

24
Children ever born- quality

• Underreporting of children ever born
• More serious for older women
• Can use certain adjustment to fix
• Failure to record childless
• Proportion of childless women too low and average
  number of children born too high.
• Still a serious problem in many countries
• Selection error
• Use women enumerated in census/survey to
  represent past experience not a big problem
  though

25
Recent births- information needed

• Did this woman have any live birth during the
  past 12 months (if multiple, indicate number)?
• OR
• What was the year and month of your most recent
  birth
• OR
• Have there been any live births in this household
  during the last 12 months?

26
Recent births- tabulations
Question 1 and 3
Age of women Number of births in the last 12 months

Question 2
Age of women of women having birth in of women having birth in of women having birth in of women having birth in
Age of women Jan 05 Feb 05 Dec 05

27
Recent births- estimation

• The questions are subject to under-reporting of
  births certain adjustment is needed
• Age of women during the census to be adjusted to
  age at giving birth

28
Recent births- quality

• Reporting errors
• Poor performance of fieldworkers
• reference period error uncertain of the date
  of birth vs the reference period
• Reluctant to report
• Selection errors
• Excluded women had a birth recently but died
  before the census
• Excluded household had a birth recently but
  dissolved before the census
• Not significant in most cases, however could
  become an issue when many deaths occurred in a
  short period (HIV/AIDS)

29
Birth histories some background

• An important source on infant and child mortality
• Include many questions, limited to 5000 or 10000
  women
• WFS or DHS
• Age-specific birth rates or mortality rates

30
Birth histories information needed

• Birth history of a woman
• All children she has had
• Living or deceased?
• Characteristics of the children
• Sex
• Date of birth
• Type of birth (single, twin etc)

31
Birth histories quality

• Reporting errors

32
Conclusion

• Methods are available when complete civil
  registration system does not exist. Civil
  registration, however, is still the best source.
• Can also be used to evaluate the quality of civil
  registration data
• Quality concerns

33
References

• Handbook on the Collection of Fertility and
  Mortality Data, United Nations (2003)
• Manual X Indirect Techniques for Demographic
  Estimation, United Nations (1983)

34
Example Romania
Age 2002 civil registration 2002 civil registration 2002 civil registration 2001 census 2001 census 2001 census   P/F
Age Births female population F Children ever born Total female P   P/F
15-19 28503 795868 0.06 798298 42648 18.72 306.75
20-24 77518 943208 0.38 852731 339884 2.51 6.67
25-29 66793 905641 0.79 829758 802501 1.03 1.31
30-34 36063 963055 1.06 955730 1367407 0.70 0.66
35-39 8395 613781 1.19 586945 1102760 0.53 0.45
40-44 2327 768725 1.22 723378 1522711 0.48 0.39
45-49 139 820343 1.23 809430 1761109 0.46 0.37
Source United Nations Demographic Yearbook
35
Example - Bahrain
Age 2002 civil registration 2002 civil registration 2002 civil registration 2001 census 2001 census 2001 census   P/F
Age Births Female Population F Children Ever born Total female P   P/F
15-19 349 25433 0.01 496 1037 0.48 47.51
20-24 2645 27373 0.10 8392 9259 0.91 3.65
25-29 4147 27436 0.15 26150 16925 1.55 1.69
30-34 3413 28453 0.12 47860 20388 2.35 1.45
35-39 2299 26342 0.09 67362 21079 3.20 1.49
40-44 655 20474 0.03 67835 17557 3.86 1.58
45-49 51 13181 0.00 49733 11645 4.27 1.70
Source United Nations Demographic Yearbook
36
Example - Kazakhstan
Age 1999 civil registration 1999 civil registration 1999 civil registration 1999 census 1999 census 1999 census P/F
Age Births Female population F Children ever born Total female P P/F
15-19 22334 705110 0.04 33746 677565 0.05 1.14
20-24 80991 653622 0.46 379186 624933 0.61 1.31
25-29 56876 560376 1.05 799505 584182 1.37 1.31
30-34 32276 529538 1.46 1120327 558784 2.00 1.38
35-39 15542 606078 1.66 1501616 615835 2.44 1.47
40-44 3120 542740 1.74 1479504 542719 2.73 1.57
45-49 205 455255 1.75 1343993 455531 2.95 1.69
Source United Nations Demographic Yearbook
37
Data availability - children ever born
Country Year of data
Egypt 1986
Bahrain 1991 and 2001
Iraq 1987 and 1997
Palestine 1997
Qatar 1986
Yemen 1994
Source United Nations Demographic Yearbook