BackgroundA rapid assessment (RA) tool was developed to rapidly and inexpensively identify key areas of weakness and to yield an overall performance score for vital registration (VR) systems. This standardised tool has now been applied in more than 70 countries, but there has been no formal evaluation of its validity or relationship with measures of socioeconomic development. Similarly, there is very little empirical research on whether better VR systems are associated with better health outcomes. We aimed to compare the RA scores to independent assessments of VR completeness and data quality; explore the relationship between the RA results and selected national socioeconomic indicators; and investigate how the RA scores correlate with key mortality indicators, controlling for levels of national income and other variables. MethodsWe regressed the overall scores (%) of the RA from 70 countries on a series of development indicators, including national income and education. We measured the correlation between overall and sub-component RA scores against alternative estimates of national VR completeness and quality. We regressed RA scores against child and adult mortality, controlling for national income. FindingsThe RA scores were consistent with external measures of completeness and quality and were robustly correlated with a number of indicators of socioeconomic development, confirming their predictive value for assessing VR systems. Completeness of civil registration was associated with better health outcomes, independent of level of national income. InterpretationOur research demonstrates the utility of RA as an overall system indicator, as well as its predictive validity in relation to development indicators. VR is not only a by-product of development that will come about organically along with economic, governance, and political maturity, but also contributes directly and indirectly to desirable development outcomes, including better health. The close correlation between assessment scores with widely available development indices enhances the utility of the tool for guiding civil registration and vital statistics development strategies. The correlation between VR systems functionality and key health and development outcomes supports our hypothesis that VR is not merely a source of data but is a driver of development and improved health status in its own right. FundingAustralian Overseas Aid.