Prof Ian Timaeus

Emeritus Professor of Demography

London School of Hygiene & Tropical Medicine
Keppel Street
United Kingdom

I started my career writing software, but worked in the Population Studies Group (previously the Centre for Population Studies) at the School from 1980 to 2021. My first degree is in social anthropology and I view myself as a social scientist, although most of my work is in technical demography or quantitative data analysis. I did an MSc in Demography at LSE and completed a PhD at the School on the estimation of adult mortality from data on orphanhood.

I am now Emeritus Professor at the School and also an Honorary Professor at the University of Cape Town.


Department of Population Health
Faculty of Epidemiology and Population Health


Centre for Data and Statistical Science for Health
Centre for Maternal Adolescent Reproductive & Child Health


I still deliver several lectures on the module on Population, Poverty and Environment as well as also occasionally lecturing on other modules such as Population Dynamics and Projections.


My research interests include methods for measuring adult mortality in developing countries, the social and demographic impact of the HIV/AIDS epidemic, inequalities in child health and welfare, and the demography of sub-Saharan Africa, in particular that of South Africa. I was one of the team that produced the 2013 web-based manual on indirect methods of estimation published by the IUSSP, Tools for Demographic Estimation.

In recent years I have been investigating patterns of parity progression and birth intervals during the transition to low fertility across the globe. This detailed analysis of family building patterns in different populations reveals that the pathways countries take to low fertility are more diverse and complex than is recognised by classical demographic transition theory.
Research Area
Adolescent health
Child health
Health inequalities
Development studies
Research methodology
Disease and Health Conditions
South Africa
United Kingdom
Sub-Saharan Africa (all income levels)

Selected Publications

Teenage Childbearing and Educational Attainment in South Africa.
TIMAEUS, IM; Moultrie, TA;
Studies in family planning
Tools for Demographic Estimation
Moultrie, TA; Dorrington, RE; Hill, AG; Hill, K; TIMAEUS, IM; ZABA, B;
International Union for the Scientific Study of Population
Mortality differentials 1991-2005 by self-reported ethnicity: findings from the ONS Longitudinal Study.
Scott, AP; TIMÆUS, IM;
Journal of epidemiology and community health
On Postponement and Birth Intervals
TIMÆUS, IM; Moultrie, TA;
Population and development review
Methods to estimate the number of orphans as a result of AIDS and other causes in Sub-Saharan Africa.
Grassly, NC; TIMAEUS, IM;
Journal of acquired immune deficiency syndromes (1999)
Mortality transition in the Ovamboland region of Namibia, 1930-1990.
Notkola, V; TIMAEUS, IM; Siiskonen, H;
Population studies
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