Data linkageThe process of establishing whether two or more pieces of information belong to or describe the same person, family, event, place or time period. is a technique for connecting pieces of information that are thought to relate to the same person, family, place or event.
Administrative information is created each time a person comes into contact with a particular service, such as the registration of a birth or death, a hospital stay or an emergency department visit. If this information can be connected for the whole population in a way that does not breach an individual's privacy, it can all be analysed to produce evidence for improvements in the health in the WA community.
Data linkage is needed because Medicare numbers, Driver's licence numbers and hospital patient numbers are all different and may not be able to connect information between different services.
Data linkage techniques in WA have been developed to ensure the best possible matching while at the same time protect personal privacy. Since there are often millions of records being linked this way, highly specialised computer programs do most of the matching. For some of the more difficult matches a Linkage Officer will look at the records and make a decision about whether it is a true match.
The establishment and early development of data linkage for health services research in WA is described in "Population-based linkage of health records in Western Australia: development of a health services research linked database" (1999, PDF).
Research using linked data is very valuable and efficient because it includes all the people in WA, not small samples of the population. This provides a more accurate picture of the health of people in WA. Linked data can be used for:
- Population based health services research and policy development
- To investigate potential projects i.e. testing hypotheses and pilot studies
- As a capture-recapture tool, to improve the quality of datasets
- For follow-up and comparison of different treatment regimes
- To study the aetiology, co-morbidities and outcomes of disease