1. Samuel Clark Department of Sociology, University of Washington Institute of Behavioral Science, University of Colorado at Boulder Agincourt Health and Population Unit, University of the Witwatersrand Indirect Estimation Techniques

2. May 30, 2006 1 Introduction  In large parts of the developing world vital registration systems do not function well, or at all  Consequently it is not possible to obtain “direct” measures of most demographic indicators  “Indirect” methods go part way to filling this gap  Will focus mainly on mortality because it is perhaps the most fundamental demographic indicator: – Social progress, health status – Program effectiveness, etc.  The indirect methods use measures of kin survival to estimate mortality

3. May 30, 2006 2 The Brass Method  Developed by William Brass …  Very common method of estimating child mortality from mothers’ reports of the survivorship of their children  Women commonly interviewed in a survey framework  Minimum necessary information: – Total number of live-born children – Total number of those children are now alive (survived) – The UN now recommends these questions for national censuses

4. May 30, 2006 3 Brass Concept  Basic idea (Hill & Figueroa, 2001): – Mothers’ age can serve as proxy for exposure time of their children – Proportion children who are dead for mothers of given age can be converted to a defined probability of dying for children of a given age  Calculate the proportion of live-born children who are dead by age of mother  Convert the proportion dead to a standard life table measure: q(a) = x q 0

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14. May 30, 2006 13 Biases / Errors / Misinterpretations  Misreport of numbers of children and surviving children  Still births reported as live births  overstates Mx  Omission of children who have moved to other households  overstates Mx  Changes in Mx level over time; corrected with the “reference period”  Changes in Fx over time – a real problem: alters the parity ratios and distorts the fertility correction multipliers – HIV – Secular declines in fertility

15. May 30, 2006 14 Biases / Errors / Misinterpretations  q(1) is a problem: – Most deaths are to first births that have above normal risks – Many early first births are to low SES women who also have above average risks – Comparatively few births in this age group and not much exposure (see lexis diagram)  Selective mortality of mothers: – Assumes child survival to children of death and living mothers is the same – Often not:  HIV correlates mortality of mothers and children, dead mothers’ children likely had higher Mx  estimate understates reality

16. May 30, 2006 15 Biases / Errors / Misinterpretations  Simulation techniques used to address, quantify and attempt to correct for some of these biases