Background

Statistical time series derived from administrative data sets form key indicators in measuring progress in addressing disadvantage in Aboriginal and Torres Strait Islander populations in Australia. However, inconsistencies in the reporting of Indigenous status can cause difficulties in producing reliable indicators. External data sources, such as survey data, provide a means of assessing the consistency of administrative data and may be used to adjust statistics based on administrative data sources.

Methods

We used record linkage between a large-scale survey (the Western Australian Aboriginal Child Health Survey), and two administrative data sources (the Western Australia (WA) Register of Births and the WA Midwives’ Notification System) to compare the degree of consistency in determining Indigenous status of children between the two sources. We then used a logistic regression model predicting probability of consistency between the two sources to estimate the probability of each record on the two administrative data sources being identified as being of Aboriginal and/or Torres Strait Islander origin in a survey. By summing these probabilities we produced model-adjusted time series of neonatal outcomes for Aboriginal and/or Torres Strait Islander births.

Results

Compared to survey data, information based only on the two administrative data sources identified substantially fewer Aboriginal and/or Torres Strait Islander births. However, these births were not randomly distributed. Births of children identified as being of Aboriginal and/or Torres Strait Islander origin in the survey only were more likely to be living in urban areas, in less disadvantaged areas, and to have only one parent who identifies as being of Aboriginal and/or Torres Strait Islander origin, particularly the father. They were also more likely to have better health and wellbeing outcomes. Applying an adjustment model based on the linked survey data increased the estimated number of Aboriginal and/or Torres Strait Islander births in WA by around 25%, however this increase was accompanied by lower overall proportions of low birth weight and low gestational age babies.

Conclusions

Record linkage of survey data to administrative data sets is useful to validate the quality of recording of demographic information in administrative data sources, and such information can be used to adjust for differential identification in administrative data.

Objective To determine the health impact of swimming pools built with the aim of improving quality of life and reducing high rates of pyoderma and otitis media.

Design Intervention study assessing prevalence of ear disease and skin infections before and at six monthly intervals after opening of swimming pools.

Setting Two remote Aboriginal communities in Western Australia.

Participants 84 boys and 78 girls aged < 17 years.

Main outcome measures Changes in prevalence and severity of pyoderma and perforation of tympanic membranes with or without otorrhoea over 18 months after opening of pools.

Results In community A, 61 children were seen before the pool was opened, and 41, 46, and 33 children were seen at the second, third, and fourth surveys. Equivalent figures for community B were 60, 35, 39, and 45. Prevalence of pyoderma declined significantly from 62% to 18% in community A and from 70% to 20% in community B during the 18 months after the pools opened. Over the same period, prevalence of severe pyoderma fell from 30% to 15% in community A and from 48% to 0% in community B. Prevalence of perforations of the tympanic membrane fell from 32% in both communities to 13% in community A and 18% in community B. School attendance improved in community A.

Conclusion Swimming pools in remote communities were associated with reduction in prevalence of pyoderma and tympanic membrane perforations, which could result in long term benefits through reduction in chronic disease burden and improved educational and social outcomes.