More Questions, More Bias? An Assessment of the Quality of Data Used for Direct Estimation of Infant and Child Mortality in the Demographic and Health Surveys
Sarah E. K. Bradley, ICF International
Expansions of the length and complexity of Demographic and Health Surveys (DHS) in recent decades has been hypothesized to affect data quality. I analyze 198 DHS Surveys to ascertain whether changes in the DHS survey instrument have led to poorer data quality and thus biased child mortality estimates. I explain the likely causes and consequences of one measure of data quality: birth displacement, disaggregated by child survival status. I then examine differences in displacement by DHS survey characteristics, including core questionnaire length and modules including HIV biomarker testing. Preliminary results indicate highlights serious problems with the birth history data. Data quality decreased in as the core questionnaire length increased from 1989-2008, and the problem—which likely biases infant and child mortality rates downwards—is greatest in sub-Saharan African surveys, net of other factors. Encouragingly, data quality appears to have improved since 2009 when the DHS questionnaire was shortened.