Ajay Tandon

Comparability of self rated health: cross sectional multi-country survey using anchoring vignettes

Abstract Objective To examine differences in expectations for health using anchoring vignettes, which describe fixed levels of health on dimensions such as mobility. Design Cross sectional survey of adults living in the community. Setting China, Myanmar, Sri Lanka, Pakistan, Turkey, and United Arab Emirates. Participants 3012 men and women aged 18 years and older (self ratings); subsample of 406 (vignette ratings). Main outcome measures Self rated mobility levels and ratings of hypothetical vignettes using the same questions and response categories. Results Consistent rankings of vignettes are evidence that vignettes are understood in similar ways in different settings, and internal consistency of orderings on two mobility questions indicates good comprehension. Variation in vignette ratings across age groups suggests that expectations for mobility decline with age. Comparison of responses to two different mobility questions supports the assumption that individual ratings of hypothetical vignettes relate to expectations for health in similar ways as self assessments. Conclusions Anchoring vignettes could provide a powerful tool for understanding and adjusting for the influence of different health expectations on self ratings of health. Incorporating anchoring vignettes in surveys can improve the comparability of self reported measures.

Validity of reported vaccination coverage in 45 countries

BACKGROUND Monitoring and assessment of coverage rates in national health programmes is becoming increasingly important. We aimed to assess the accuracy of officially reported coverage rates of vaccination with diphtheria-tetanus-pertussis vaccine (DTP3), which is commonly used to monitor child health interventions. METHODS We compared officially reported national data for DTP3 coverage with those from the household Demographic and Health Surveys (DHS) in 45 countries between 1990 and 2000. We adjusted survey data to reflect the number of valid vaccinations (ie, those administered in accordance with the schedule recommended by WHO) using a probit model with sample selection. The model predicted the probability of valid vaccinations for children, including those without documented vaccinations, after correcting for bias from differences between the children with and without documented information on vaccination. We then assessed the extent of survey bias and differences between officially reported data and those from DHS estimates. FINDINGS Our results suggest that officially reported DTP3 coverage is higher than that reported from household surveys. This size of the difference increases with the rate of reported coverage of DTP3. Results of time-trend analysis show that changes in reported coverage are not correlated with changes reported from household surveys. INTERPRETATION Although reported data might be the most widely available information for assessment of vaccination coverage, their validity for measuring changes in coverage over time is highly questionable. Household surveys can be used to validate data collected by service providers. Strategies for measurement of the coverage of all health interventions should be grounded in careful assessments of the validity of data derived from various sources.

Comparative efficiency of national health systems: cross national econometric analysis

Abstract Objective: To improve the evidence base for health policy by devising a method to measure and monitor the performance of health systems. Design: Estimation of the relation between levels of population health and the inputs used to produce health. Setting: 191 countries. Main outcome measure: Health system efficiency (performance). Results: Estimated efficiency varied from nearly fully efficient to nearly fully inefficient. Countries with a history of civil conflict or high prevalence of HIV and AIDS were less efficient. Performance increased with health expenditure per capita. Conclusions: Increasing the resources for health systems is critical to improving health in poor countries, but important gains can be made in most countries by using existing resources more efficiently. What is already known on this topic Evidence on the effectiveness of health system reforms is scarce Studies have not used a consistent framework for specifying goals or measuring outcomes What this study adds Countries with the best levels of health do not always have efficient health systems Efficiency is related to expenditure on health per capita, especially at low expenditure The methods of measuring performance provide a basis for identifying policies that improve health and for monitoring reforms

Healthy life expectancy: comparison of OECD countries in 2001

Objectives: To compare average levels of population health for Australia and other OECD countries in 2001.

From wealth to health: modelling the distribution of income per capita at the sub-national level using night-time light imagery

BackgroundSub-national figures providing information about the wealth of the population are useful in defining the spatial distribution of both economic activity and poverty within any given country. Furthermore, since several health indicators such as life expectancy are highly correlated with household welfare, sub-national figures allow for the estimation of the distribution of these health indicators within countries when direct measurement is difficult.We have developed methods that utilize spatially distributed information, including night-time light imagery and population to model the distribution of income per capita, as a proxy for wealth, at the country and sub-national level to support the estimation of the distribution of correlated health indicators.ResultsA first set of analysis are performed in order to propose a new global model for the prediction of income per capita at the country level. A second set of analysis is then confirming the possibility to transfer the country level approach to the sub-national level on a country by country basis before underlining the difficulties to create a global or regional models for the extrapolation of sub-national figures when no country data set exists.ConclusionsThe methods described provide promising results for the extrapolation of national and sub-national income per capita figures. These results are then discussed in order to evaluate if the proposed methods could not represent an alternative approach for the generation of consistent country specific and/or global poverty maps disaggregated to some sub-national level.