The WA Data Linkage System (WADLS) was formally established in 1995 as a collaboration between the Department of Health WA, the University of Western Australia (UWA), Telethon Kids Institute (then the Telethon Institute for Child Health Research) and Curtin University. Recognising the potential community benefit of using linked health data for research, the initial setup and operational costs of the WADLS were met through grant funding from the WA Lotteries Commission.
In 1997 the Department of Health WA took over as majority funder and the Data Linkage Unit (or Data Linkage Branch, now known as Data Linkage Services) was established.
WA Health manages the WADLS, creating and maintaining linkages within and between a wide range of datasets. These linkages use rigorous, internationally accepted privacy preserving protocols, probabilistic matching, clerical review and quality control mechanisms to create a robust and complex system of links between otherwise disparate pieces of individual information. Linked data can be requested for ethically approved research, planning and evaluation projects which show benefit to the lives of Western Australians.
WA Health has been a pioneer of innovation in Data Linkage techniques and surrounding processes and protocols. Examples include:
- The development of assorted value-adding data enhancements, such as geocoding functions and related spatial data (1997), the family connections system and genealogical links (2007), and the derived Aboriginal and Torres Strait Islander status flag (2012);
- Linkages of non-government datasets, including St John Ambulance (2001 onwards), Silver Chain Nursing Association (2003 onwards) and Brightwater Care Group (2016);
- The introduction of a Client Services Team in 2005 and formalised application process in 2008, which has supported hundreds of projects relating to planning, service evaluation and research;
- Pioneering cross-agency linkages with the Registry of Births, Deaths and Marriages (1996) and State Electoral Commission (1999), and later via the Road Safety Project and Developmental Pathways Project (both 2006);
- Undertaking the first linkage of Commonwealth MBS/PBS data in 2004;
- Streamlining the delivery of linked data through the Custodian Administered Research Extract Server (CARES) in 2013;
- Publicly available activity metrics (since 2015);
- The rapid and continuous growth of the WADLS, from 4 routinely linked datasets in 1995 to around 50 in 2016 – collectively comprising well over one hundred million records!