Centre for Eye Research Australia, University of Melbourne, Victoria.
Aust N Z J Public Health. 2010 Dec;34(6):554-62. doi: 10.1111/j.1753-6405.2010.00635.x.
To review the process of sample selection and highlight the methodological difficulties encountered during a nationwide survey of Indigenous Australians, to determine the prevalence and causes of vision impairment and evaluate access to and utilisation of eye care services.
Using a multi-stage, random cluster sampling methodology, 30 geographic areas stratified by remoteness, were selected to provide a representative population of approximately 3,000 Indigenous Australians aged 5-15 and 40 years and older, and a small non-Indigenous sample in selected remote areas. Recruitment was adapted to local conditions. The rapid assessment methodology included a questionnaire, tests of visual acuity, trachoma grading, frequency doubling perimetry and non-mydriatic fundus photography.
The number of people examined was 2883/3662 (78.7%) Indigenous and 136 (83.4%) non-Indigenous. The percentage of the expected population who were enumerated during the survey varied; discrepancies were largest in urban areas (34.5%) compared to very remote areas (97.1%).
The unexpected variation in predicted population numbers and participation rates could be explained in part by local circumstances, degree of urbanisation, interpretation of the definition of 'Indigenous' and time constraints.
For successful recruitment, a community-specific approach is essential, including collaboration with local organisations and liaison with health workers of each gender.
回顾样本选择过程，并强调在一项针对澳大利亚原住民的全国性调查中遇到的方法学困难，以确定视力障碍的患病率和原因，并评估眼保健服务的可及性和利用情况。
采用多阶段、随机聚类抽样方法，选择 30 个地理位置按偏远程度分层的地理区域，以提供大约 3000 名 5-15 岁和 40 岁及以上的澳大利亚原住民以及选定偏远地区的一小部分非原住民样本的代表性人群。根据当地情况调整了招募工作。快速评估方法包括问卷调查、视力测试、沙眼分级、倍频视野检查和非散瞳眼底照相。
接受检查的人数为 2883/3662 名原住民（78.7%）和 136 名非原住民（83.4%）。在调查期间，被统计的预期人口比例有所不同；城市地区（34.5%）与非常偏远地区（97.1%）的差异最大。
预测人口数量和参与率的意外变化部分可以用当地情况、城市化程度、对“原住民”定义的解释以及时间限制来解释。
为了成功招募，需要采取特定于社区的方法，包括与当地组织合作以及与每个性别的卫生工作者联系。
