Lumos is a program that links deidentified patient information from general practices and hospital services to understand how patients use health services in NSW.

Health system management relies on high quality data for making decisions that can improve the delivery of services. Lumos provides information about people who go to general practices in NSW that have chosen to participate. As this is a sample of the NSW population, its usefulness depends on how closely the information in the Lumos data represent the broader population.

How well do Lumos data represent the NSW 2022 population?

A 2022 study of Lumos’ representativeness and health system use

Bouckley, Myton-Katieva et al¹ present a retrospective cohort study to determine the representativeness of Lumos data.

The study used patient data extracted for 5.2 million unique patients from 628 general practices. At the time, this comprised approximately 25% of NSW general practices and 50% of the population.

Reviewing active² Lumos general practice patients in 2022, they found:

• Lumos was representative of the general population in relation to sex, rurality, age, and most socioeconomic measures
• Strong geographic coverage by Lumos data, with opportunities to increase coverage of southwest and northeast NSW
• Increased general practice encounters and hospital admissions were associated with greater relative socioeconomic disadvantage and age.

Across 2022, every 100 pateints averaged:

• 530 general practice encounters
• 38 hospital admissions
• 48 emergency department presentations

This study presents one of the most comprehensive summaries of whole-of health system service use in NSW, grouped by key sociodemographic characteristics.

What does this mean?

Lumos is a reliable source of data for informing health system improvement that bridges primary (GP) and hospital care data. Lumos provides a powerful planning and evaluation tool that:

• overcomes historical challenges with disconnected health service data,
• contains data suitable for generating insights in population sub-groups, including by sex, rurality, age and socioeconomic measures.

All users and stakeholders of Lumos – including GPs, Primary Health Networks, NSW Health and academia in partnership with health services – can rely on Lumos providing a trustworthy representation of the health system for further analysis.

More about Lumos and the study

Lumos is the largest collaboration between NSW general practices, NSW Health and NSW Primary Health Networks (PHNs) to date. This study was completed by The George Institute for Global Health, comparing Lumos data to the 2021 census.

Lumos combines deidentified data from general practices, hospitals and other health services. For more information on the steps between data collection and release of data for analytics, see Lumos Data Timing explained.

Lumos does not currently include Aboriginal Medical Services and the Aboriginality of patients cannot be identified in the data. Lumos is working with Aboriginal leaders and communities to implement Indigenous Data Sovereignty and Governance to address this gap.

By August 2025, Lumos had grown to over 800 general practices and 7 million unique patients, increasing coverage and addressing data gaps. Lumos continues to expand

References

1. Bouckley T, Myton-Katieva R, Peiris D, et al. An assessment of data quality and sociodemographic variation in health service utilisation of general practice, emergency department and admitted services in a New South Wales linked health data asset: a retrospective cohort study of Lumos. BMJ Open 2025;15:e102055.
2. ‘Active patients’ are those who had at least one record within Lumos linked GP, admitted patient, Emergency Department, non-admitted patient, mental health ambulatory, or NSW Ambulance datasets in 2022.