Objectives: The 1999 World Bank report claimed that growth in gross domestic product (GDP) between 1960 and 1990 only accounted for 15% of concomitant growth in life expectancy in developing countries. These findings were used repeatedly by the World Health Organization (WHO) to support a policy shift away from promoting social and economic development, towards vertical technology-driven programmes. This paper updates the 1999 World Bank report using the World Bank's 2005 dataset, providing a new assessment of the relative contribution of economic growth.

Study design: Time-series analysis.

Methods: Cross-sectional time-series regression analysis using a random effect model of associations between GDP, education and technical progress and improved health outcomes. The proportion of improvement in health indicators between 1970 and 2000 associated with changes in GDP, education and technical progress was estimated.

Results: In 1970, a 1% difference in GDP between countries was associated with 6% difference in female (LEBF) and 5% male (LEBM) life expectancy at birth. By 2000, these values had increased to 14% and 12%, explaining most of the observed health gain. Excluding Europe and Central Asia, the proportion of the increase in LEBF and LEBM attributable to increased GDP was 31% and 33% in the present analysis, vs. 17% and 14%, respectively, estimated by the World Bank. In the poorest countries, higher GDPs were required in 2000 than in 1970 to achieve the same health outcomes.

Conclusions: In the poorest countries, socio-economic change is likely to be a more important source of health improvement than technical progress. Technical progress, operating by increasing the size of the effect of a unit of GDP on health, is likely to benefit richer countries more than poorer countries, thereby increasing global health inequalities.