Data linkage brings together data from multiple sources to better understand the complex interactions Australians have with health and welfare services. 

Data are collected whenever a person engages with the health system, from seeing their GP and collecting a script to presenting to hospital or outpatient services. The way this data is collected differs across the states and territories, but also across the health service sector making it difficult to connect, compare and measure over time. 

Linked data systems (or assets) bring these data sources together, making it easier for researchers to conduct complex cross-sector and cross-jurisdictional research. This research can be used to improve health policies, provide better access to services, and inform treatment pathways and care for chronic disease management, for the benefit of all Australians. 

The AIHW holds and arranges access to 4 linked data systems.

National Health Data Hub (NHDH)

Find out more about NHDH

National Disability Data Asset (NDDA)

Find out more about NDDA

COVID-19 register and linked data set

Find out more about the COVID-19 register

Child Wellbeing Data Asset (CWDA)

FIND OUT MORE ABOUT CWDA

Guiding principles for the AIHW linked data systems 

The Australian data landscape in which linked assets are being designed and developed is rapidly changing. The AIHW seeks to adapt to the constant emergence of new data assets, systems, technologies, and interested parties.

In the development of linked data systems, the AIHW observes the following guiding principles: 

  • Privacy by design. We embed privacy at the integration system, asset, and project level. 
  • Minimise the need to share and use personal information. We use a distributed linkage model where possible, in which state & territory data linkage units link to a common spine (directory) with the AIHW and share information through de-identified maps.
  • Share once and use many times. We reuse existing pipelines of data supply with new authorisations. 
  • Employ efficient methodologies and processes. We design and use fit-for-purpose methodologies and processes in all integration activities. 

The delivery of these linked data systems positions the AIHW favourably to continue to deliver on our core purpose: to support stronger evidence, better decisions and improved health and welfare. 

Privacy and confidentiality

The AIHW has a long history in managing data linkage safely and securely, with more than 35 years of experience linking data, for example cancer data with national deaths data. 

As an accredited integrating authority and an Accredited Data Service Provider under the Data Availability and Transparency Act 2022, we are committed to protect personal data and safeguard your privacy. This commitment is underpinned by law.

We do this by:

  • collecting and using personal information in accordance with the Privacy Act 1988

  • removing identifying data (such as names and addresses) so that a person cannot be identified

  • storing personal identifiers separately from other data so that no one can see personal identifiers and analytical data at the same time 

  • embedding the Five Safes Framework – an internationally recognised approach to considering strategic, privacy, security, ethical and operational risks associated with data sharing or release 

  • providing a secure environment for authorised researchers to use the linked data asset

  • managing relationships with data custodians to ensure accountability and appropriate use of linked data assets.

All projects using the linked data systems must have ethical approval from the AIHW Ethics Committee.

The AIHW’s data governance framework provides more information about measures we are taking to manage data safely and protect your privacy.