1. Unconventional Approaches to Mortality Estimation
Assessment of Developing Country and Historical Data for Inclusion in HMD
Kenneth Hill
Ian Timæus

2. The Issue:
HMD is built from components needed to calculate Occurrence-Exposure rates
Comparability
Flexibility
Accessibility
Reproducibility
Most developing countries do not have standard data for calculating O-E rates
How well do alternative ways for estimating mortality in LDC’s fit with HMD?

3. Broad Approaches Evaluation and adjustment of registered deaths
Alternative data collection mechanisms
Indirect methods based on survival of close relatives
Intercensal survival

4. Evaluation and Adjustment of Registered Deaths
Evaluation methods compare mortality rates by age with the age distribution
Early methods assumed population stability
More recent methods do not assume stability, but require 2 census enumerations and still make strong assumptions:
Net migration is either negligible or known (but recent exploration of ways of measuring migration)
Errors of omission (from population, deaths) are invariant by age

5. Evaluation and Adjustment Methods
Growth Balance methods compare the observed death rate age x+ to a residual estimate obtained by subtracting growth rate x+ from entry rate x+
Synthetic Extinct Generations methods compare estimate of population age x derived from deaths over age x and growth rates x+ to observed population age x (N.B. SEG assumes no change in census coverage)

6. Death reporting and census coverage England & Wales, 1841-1911

7. England and Wales - data sources
Deaths – General Register Office annual reports
Census counts – 1841 and every 10 years to 1911 (HMD database contains population estimates for 1 January each year)
Compare deaths in each 11-year interval with the bordering population estimates e.g. 1/1/41-31/12/51

8. Methods of analysis
England and Wales experienced significant net emigration throughout the 19th and early 20th centuries
Three series of Generalized Growth Balance estimates:
no migration
Dudley Baines’ (1985) migration estimates
GGB method applied iteratively to estimate migration
Final estimates from Bennett-Horiuchi method after adjusting for changing census coverage

9. GGB – initial fit (ignoring migration) Men, 1841-1851

10. GGB – estimating migration Men, 1841-1851

11. GGB – final estimates Men, 1841-1851

12. Bennett-Horiuchi method Men, 1841-1851

13. Net migration from England & Wales Baines’ and GGB estimates

14. Estimated census coverage (relative to 1841)

15. Completeness of death registration (relative to bordering population estimates)

16. Conclusions – England and Wales
Even fairly small net migration flows introduce significant uncertainty into evaluation of the relative completeness of deaths and population data
In E&W , neither source suffers from major deficiencies
Conventional wisdom about the scale of emigration during the 19th century leads to the view that the deaths data are about 5 per cent more complete than the census data throughout the period
If 1 million more people than this emigrated, the data series can be largely reconciled, suggesting that the unadjusted death rates are fairly accurate

17. Alternative Data Collection Methods
Sample registration systems
Deaths by age and sex in recent period collected by a population census
Amenable to same methods of evaluation as death registration
May be less susceptible to selection bias

18. Survival of Close Relatives
Mothers’ reports of survival of children:
Aggregate
Individual (birth history)
Children’s reports of survival of parents:
All respondents’ reports of survival of siblings
Individual (sibling history) - usually limited to respondents of reproductive age but collection from all respondents could permit more formal evaluation

19. Intercensal Survival Methods
Standard survivorship ratios
Cumulative mortality through growth rates (Preston and Bennett)
Very sensitive to change in census coverage and age exaggeration

20. Conclusions: Potential for inclusion in HMD
Evaluated vital registration or similar data plus birth histories for child mortality best meet criteria:
What inclusion criteria to apply?
Selection biases
Sibling survival (for recent period from large surveys) might prove acceptable
Indirect approaches are not promising