PUBLICATION: Population Health Metrics
Oti, S.O., & C. Kyobutungi
Background: Developing countries generally lack complete vital registration systems that can produce cause of death
information for health planning in their populations. As an alternative, verbal autopsy (VA) – the process of interviewing
family members or caregivers on the circumstances leading to death – is often used by Demographic Surveillance
Systems to generate cause of death data. Physician review (PR) is the most common method of interpreting VA, but
this method is a time- and resource-intensive process and is liable to produce inconsistent results. The aim of this
paper is to explore how a computer-based probabilistic model, InterVA, performs in comparison with PR in interpreting
VA data in the Nairobi Urban Health and Demographic Surveillance System (NUHDSS).
Methods: Between August 2002 and December 2008, a total of 1,823 VA interviews were reviewed by physicians in the
NUHDSS. Data on these interviews were entered into the InterVA model for interpretation. Cause-specific mortality
fractions were then derived from the cause of death data generated by the physicians and by the model. We then
estimated the level of agreement between both methods using Kappa statistics.
Results: The level of agreement between individual causes of death assigned by both methods was only 35% (κ = 0.27,
95% CI: 0.25 – 0.30). However, the patterns of mortality as determined by both methods showed a high burden of
infectious diseases, including HIV/AIDS, tuberculosis, and pneumonia, in the study population. These mortality patterns are consistent with existing knowledge on the burden of disease in underdeveloped communities in Africa.
Conclusions: The InterVA model showed promising results as a community-level tool for generating cause of death
data from VAs. We recommend further refinement to the model, its adaptation to suit local contexts, and its continued
validation with more extensive data from different settings.
Catherine holds a PhD (2006) in Epidemiology from the University of Heidelberg, and a Master of Science (2002) in Community Health and Health Management. She is the Director of Research at the African Population and Health...