Tobias Martin, Searle Paula
New Zealand Ministry of Health, New Zealand.
Aust N Z J Public Health. 2006 Oct;30(5):457-60. doi: 10.1111/j.1467-842x.2006.tb00464.x.
To quantify the potential contribution of inter-district relative to intradistrict variation to the Maori disparity in life expectancy in 2000-02, by counterfactual modelling. SETTING, DATA SOURCES AND METHODS: The setting was New Zealand's 21 health districts (District Health Boards, DHBs). All data (population estimates and life expectancy estimates) were sourced from Statistics New Zealand and relate to the 2000-02 period. Maori life expectancy (nationally) was recalculated under the counterfactual that Maori life expectancy in each DHB did not differ from total population life expectancy in the corresponding DHB (so eliminating intra-district variation). The difference between the observed total population and counterfactual Maori life expectancies therefore represents the contribution of inter-district variation to the Maori life expectancy disparity.
Observed total population and Maori life expectancies at birth in 2000-02, pooling sexes, were 78.7 and 71.1 years respectively, giving a total disparity of 7.6 years. Under the counterfactual, Maori life expectancy increased to 78.4 years (and total population life expectancy to 79.0 years). Inter-district variation was therefore estimated to potentially contribute only 0.6 years or 8% to the total Maori disparity. Allowing for imprecision, inter-district variation almost certainly accounts for less than 10.5% of the total disparity.
Inter-district or geographic variation makes only a small contribution to the total Maori disparity in life expectancy. Adjustment or standardisation for district is not necessary when comparing Maori and non-Maori health outcomes. If the policy goal is to reduce ethnic inequalities in health, then the focus of policy (e.g. funding formulae) needs to be on factors directly linked to ethnicity, rather than on geographic variations in health and health care that have an impact on all ethnic groups more-or-less alike.
通过反事实建模，量化2000 - 2002年间地区间差异相对于地区内差异对毛利人预期寿命差距的潜在贡献。
设置、数据来源和方法：研究对象为新西兰的21个健康区（地区卫生局，DHBs）。所有数据（人口估计数和预期寿命估计数）均来自新西兰统计局，且与2000 - 2002年期间相关。在每个地区卫生局毛利人的预期寿命与相应地区卫生局总人口的预期寿命无差异这一反事实情况下，重新计算了全国毛利人的预期寿命（从而消除地区内差异）。因此，观察到的总人口预期寿命与反事实毛利人预期寿命之间的差异代表了地区间差异对毛利人预期寿命差距的贡献。
2000 - 2002年出生时观察到的总人口和毛利人的预期寿命，合并两性后分别为78.7岁和71.1岁，总差距为7.6岁。在反事实情况下，毛利人的预期寿命增至78.4岁（总人口预期寿命增至79.0岁）。因此，估计地区间差异对毛利人总差距的潜在贡献仅为0.6岁或8%。考虑到不精确性，地区间差异几乎肯定占总差距的比例不到10.5%。
地区间或地理差异对毛利人预期寿命的总差距贡献很小。在比较毛利人和非毛利人的健康结果时，无需对地区进行调整或标准化。如果政策目标是减少健康方面的种族不平等，那么政策重点（如资金分配公式）应放在与种族直接相关的因素上，而不是放在对所有种族群体或多或少都有影响的健康和医疗保健的地理差异上。
