Local Government Area

The Local Government Area boundaries (LGAs) used in HealthStats NSW are an Australian Bureau of Statistics (ABS) approximation of officially gazetted LGAs as defined by the NSW Office of Local Government. The 2021 Australian Statistical Geography Standard (ASGS) edition of LGAs includes 130 LGAs in NSW.

LGAs cover incorporated areas of Australia. Incorporated areas are legally designated parts of a State or Territory over which incorporated local governing bodies have responsibility. The major areas of NSW not administered by incorporated bodies include parts of far western NSW and Lord Howe Island. These regions are identified as ‘Unincorporated’ in the ABS Local Government Area structure.

Local Government Area population estimates used in HealthStats NSW

In HealthStats NSW, the total population used for each LGA in age-standardisation calculations is the most recent Estimated Resident Population produced by the ABS, which are based on the 2021 Census and projections from the current ERP  produced by the NSW Department of Planning, Housing, and Infrastructure. 

Methods used to adjust estimates for small areas

The term ‘small area’ refers to a small geographical area and a small population. Data from a small area are characterised by considerable variability. Smoothing is a general term for methods of minimising variability in data. Examples include rounding, moving averages, extending the period of time in which cases are counted or increasing the size of areas considered. In addition, statistical smoothing can be used to adjust raw estimates in small areas by taking into account information from adjacent areas (local or spatial variability) and from the whole state (global or non-spatial variability).

LGAs are the smallest level at which data are analysed in HealthStats NSW. 'Statistical smoothing' methods are used to control for random variability in the small area estimates and result in more conservative estimates for small areas. These methods are described in the Spatial Adjustment HealthStatsPLUS paper.

The results of the spatial adjustment can be used to determine if the results obtained from individual areas are significantly different from overall NSW outcomes.

References:

NSW Office of Local Government website at: https://www.olg.nsw.gov.au/

Australian Bureau of Statistics. Local Government Areas. Australian Statistical Geography Standard. Edition 3, 2021. Accessed 24/04/2024 at https://www.abs.gov.au/statistics/standards/australian-statistical-geography-standard-asgs-edition-3/jul2021-jun2026/non-abs-structures/local-government-areas

NSW Department of Planning, Housing, and Infrastructure website at: https://www.nsw.gov.au/departments-and-agencies/department-of-planning-housing-and-infrastructure