Disparities in health: common myths and uncommon truths

A reappraisal of disparities by deprivation provides new and important information. NZDep96 is an area-based index of socioeconomic deprivation that uses nine variables measured in the 1996 census. The distribution of the Māori ethnic group is sharply skewed towards the most deprived deciles with only three percent in decile 1 and twenty-six percent residing in decile 10 meshblocks. More than half (56%) of Māori live in areas represented by the three most deprived deciles. This pattern is consistent within both sectors of the Māori ethnic group: sole Māori--those who give Māori as their only ethnicity and mixed Māori--those who give Māori as only one of their ethnicities. This is a 'distribution gap'. Within disparities analysis, there is also evidence of an 'outcome gap'. That is, the health outcomes of Māori are different from non-Māori, even after controlling for deprivation. For example, overseas data on life expectancy at birth have demonstrated social class gradients with lower life expectancy among manual workers and increasing life expectancy for trades-people, through to managerial and professional workers. This gradient is also evident in Aotearoa with life expectancy at birth decreasing as deprivation increases. A third dimension is evident in a review of disparities by deprivation,--a 'gradient gap'. This describes the relationship between ethnicity and increasing deprivation. It is as if the effect of increasing deprivation compounds risk for Māori whereas Pākehā do not seem subject to this effect. Analyses that foreground disparities have been portrayed as oppositional or secondary to Māori health development. In such frameworks where a disparity focus intersects with a development focus, the impression is given that the two are interconnected but move past each other in different directions. Our analysis promotes the disparities focus and the development focus as parallel reinforcing variables, each informing the other in the design and provision of services that have as their starting point, Māori needs. These services offer hope and opportunity for Māori but risk the vulnerability of special provision services (e.g. cuts in government expenditure). Furthermore the may delay the imperative of addressing the societal drivers that perpetuate disparities. This tension to engage in remedial reform is an important dilemma in Māori health development.