What explains widening geographic differences in life expectancy

The ongoing collection, analysis, and dissemination of routine health statistics is essential for monitoring the health of populations. 1 While the main function of such routine data analysis is to provide surveillance for particular health conditions, it may also serve to generate and support hypotheses about the causes of changes in population health. In this issue, Pearce and Dorling 2 analyse routine data to show that differences in life expectancy between New Zealand’s 21 health districts have widened from 1980 to 2000. More specifically, they show that life expectancy increased for all areas, but the areas that were least deprived in 2001 saw larger life expectancy gains since 1980 than did the most-deprived areas. Similar results have also been seen for the U