Victorian Aboriginal Affairs Report 2019 (VGAAR)

An assessment of progress is made by examining data from 2008 (or closest to) until the latest available data at the time of reporting, in 2019. The baseline year is 2008 as this was the year in which the National Indigenous Reform Agreement was established. The Report uses most recent available data and limitations are indicated where appropriate in the Report. Some data sets have different sampling approaches and time-series, particularly in the use of comparison data for non-Aboriginal people (or whole-of-population). In some instances, comparable non-Aboriginal or Victoria-wide data is not available to support group comparisons. \r\nIn these instances, proxy data is used. For example, ABS data from Aboriginal-specific surveys such as the National Aboriginal and Torres Strait Islander Health and Social Surveys are used to inform some indicators. The most comparable equivalent data for non-Aboriginal Victorians is the Victorian Population Health Survey which has a different sampling approach and time series. This approach, while liable to sampling bias, has been used by Victorian population health researchers and is methodologically sound. Aboriginal data has unique challenges. Small population sizes mean that there is a diminished ability to detect trends and changes for a given outcome (minimum detectable effect), and a greater degree of data volatility leading to large fluctuations between time points. This means there is a higher threshold for determining improvement at a statistically significant level compared to general population data. The Report identifies where trends are suggestive of improvement or deterioration but are compromised by data volatility or small numbers. \r\n

本研究以2008年（或最接近的对应年份）至2019年报告发布时可获取的最新数据为分析样本，评估相关进展。基准年设定为2008年，因该年《全国原住民改革协定（National Indigenous Reform Agreement）》正式确立。本报告采用当前可获取的最新数据，并在报告中适当位置标注数据局限性。部分数据集采用了差异化的抽样方法与时间序列，在对比非原住民人群（或全人口）数据时表现得尤为突出。部分场景下，可用于群体对比的非原住民或全维多利亚州范围内的可比数据无法获取。
在此类场景中，研究人员将采用替代数据开展分析。例如，针对部分指标，本报告采用了澳大利亚统计局（Australian Bureau of Statistics，ABS）针对原住民的专项调查数据，如《全国原住民与托雷斯海峡岛民健康与社会调查（National Aboriginal and Torres Strait Islander Health and Social Surveys）》。针对非原住民维多利亚州人群，最具可比性的等效数据来自《维多利亚州人口健康调查（Victorian Population Health Survey）》，该调查采用了不同的抽样方法与时间序列。尽管该方法存在抽样偏差风险，但已被维多利亚州人口健康研究领域广泛采用，且方法学上具备合理性。
原住民相关数据存在独特的研究挑战。由于人口规模较小，针对特定结局的趋势与变化检测能力被削弱（即最小可检测效应minimum detectable effect偏低），且数据波动性更高，不同时间点间会出现较大波动。这意味着相较于普通人群数据，要达到统计学显著性水平以判定改善情况，需要更高的阈值。本报告会标注那些虽提示改善或恶化，但因数据波动或样本量过小而可靠性受限的趋势。