Health Economics, Policy and Law (2010), 5, 1–11
& Cambridge University Press 2009 doi:10.1017/S1744133109990119
How can demography inform health policy?
TIZIANA LEONE*
Senior Research Fellow, LSE Health, London School of Economics, London, UK
Abstract : Demography’s contribution to health policy debates comes from the
study of population dynamics relating to fertility, mortality and migration. The
aim of this article is to stress how vital a correct understanding of population
dynamics is for health policy and planning. The article first highlights some of
the major contributions demographers have made to debates about health,
particularly where they have helped to overcome misconceptions. It then
discusses two prominent issues: population ageing in the developed world and
population growth in developing countries.
Demography is usually defined as the study of human populations – their size,
growth, density and distribution – and statistics regarding birth, marriage, disease
and death. Demographers have often suffered from ‘identity’ crises when trying to
locate themselves within a scientific discipline. By nature, demography is a multi-
disciplinary subject, which emphasises rigorous data analysis using specific methods
accompanied by theory that is often associated with sociology, statistics, anthro-
pology, economics and public health, among others. According to some scholars,
health demography has become a discipline in its own right (Pol and Thomas, 2001).
Undoubtedly, demography’s major contribution to health policy comes from
the study of population dynamics in the form of the determinants of fertility,
mortality and migration. Within these areas of study, demographers have often
been involved in the analysis of family dynamics, kinship effects and child
development. In the study of mortality, demographers are usually more con-
cerned with its implications for overall population size and structure, and
consequently tend to ignore rare causes of death.
What is sometimes less clear is how demographers contribute to health policy
debates. The aim of this article is to stress how a correct understanding of
population dynamics is vital for health policy and planning. The article first
highlights some of the major contributions demographers have made to debates
about health, particularly where they have helped to overcome misconceptions.
It then discusses, in more depth, two issues that I believe to be among the most
prominent in these debates: population ageing in the developed world and
population growth in developing countries.
*Correspondence to: Dr Tiziana Leone, LSE Health, London School of Economics, Houghton Street,
London WC2A 2AE, UK. Email: t.leone@lse.ac.uk
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Demographers and health
Health policy development involves three stages: identifying the major disease
problems, designing health care systems and defining what governments can do
using the full range of policy instruments (Jamison and Mosley, 1991). Coherent
health policies need to be strong in all three areas. Demographers have been
crucial in the first stage, since population changes are a key component of
changing health needs. Demographic analysis looks at behavioural changes in the
population and how these might change a population’s structure (age) and
composition (gender, race, and so on) in the medium and long term. Demo-
graphers have also helped in developing public health programmes and designing
instruments to monitor and evaluate the long-term goals of these programmes –
particularly those targeted at older people and infants (Nam, 1979).
Additionally, demographers have contributed to the debate on differences in
mortality by sex and socio-economic status. While biology is a fundamental
component, social and behavioural factors have proved to be as important (Mar-
mot et al., 1995). For example, life-course demography has been key to under-
standing the impact of parental choices and behaviours on child development, while
longitudinal and panel studies have been vital in elucidating lone parenthood effects
on child health and assessing the impact of HIV/AIDS-related deaths on household
composition, kinship and informal care (Ford and Hosegood, 2005).
The demographic transition
The main contribution of demographic thinking to wider debates about popu-
lation change is the demographic transition theory. This has had a deep impact
on the work of national and international agencies in both the developed and
the developing world for the last 50 years. The theory identifies different stages
of demographic transition based on fertility and mortality levels, ranging from
stage one, when fertility and mortality are balanced at very high levels; to stage
two, when mortality starts to decrease and fertility subsequently declines; to the
third stage, when population growth is close to zero, with low birth and death
rates. This pattern has been experienced by every country in the developed
world and has been crucial for studies of the relationship between fertility and
mortality. One of the major implications of the developed-world demographic
studies based on this model has been the realisation that fertility decline in the
developing world is not necessarily dependent on increasing industrialisation or
modernisation, as it was in developed countries (Caldwell, 1976).
The lifespan debate
The contribution of demographers to the current debate on whether human lifespan
is fixed has also been crucial. Life expectancy has increased steadily over the last 140
years in many countries and some have argued that there is a fixed ‘maximum’
2 T I Z I A N A L E O N E