Tired of breaking your head on how to construct comparable measures of poverty? Remotely sensed data on artificial night time light may be a good proxy. From a study published by Noor et al in in Population Health Metrics:
Population health is linked closely to poverty. To assess the effectiveness of health interventions it is critical to monitor the spatial and temporal changes in the health indicators of populations and outcomes across varying levels of poverty. Existing measures of poverty based on income, consumption or assets are difficult to compare across geographic settings and are expensive to construct. Remotely sensed data on artificial night time lights (NTL) have been shown to correlate with gross domestic product in developed countries.
Notice any differences?