Uses of mortality statistics
Earlier in this Module, you learned that births and deaths are the essential determinants of national demographic characteristics.
Exercise
Why would this not necessarily be the case at a provincial or district level?
At a national level, it is usually reasonable to assume that migration is a relatively insignificant component of population change relative to the overall population size and the numbers of births and deaths. For smaller administrative units (provinces, regions, districts etc.), however, migration can often be the single greatest determinant of population size.
Data on mortality are used for many different purposes. They are required as inputs into population projections (introduced in PAPP101_S10 
), which themselves are used for a variety of policy-related and planning purposes.
On a shorter time-scale, mortality statistics provide an important indicator of the health and well-being of a population. Mortality statistics are required to estimate summary measures of population health, for example the life expectancy at birth (encountered in the next two modules), as well as to understand differentials in population health among different sub-groups in the population.
Probably most importantly, mortality statistics provide information about the nature and efficacy of health care delivery systems. Thus, for example, if high levels of child mortality are observed, this may spur interventions to improve child health through changing models of care and service provision, availability of immunisation programmes etc. To be truly useful, however, it is important that information is not only collected on the numbers of deaths by age and sex, but also to be able to attribute death to its underlying cause. Where information on cause of death is also collected, data on mortality can assist in helping policymakers understand a country’s trajectory through the epidemiological transition. For this reason, it is recommended practice that the process of certifying death records not only the basic demographic characteristics of the deceased, but also for a cause of death and occupation to be recorded.
Information on cause of death is also important for epidemiological studies: the links between exposure to asbestos and higher mortality were first identified by observing that people who worked in environments with high levels of asbestos particles present suffered not only elevated mortality, but also tended to have higher death rates from lung-related diseases.