title: Accuracy and completeness of patient pathways--the benefits of national data linkage in Australia.
abstract: BACKGROUND
  The technical challenges associated with national data linkage, and the extent of cross-border population movements, are explored as part of a pioneering research project. The project involved linking state-based hospital admission records and death registrations across Australia for a national study of hospital related deaths.
  
  
  METHODS
  The project linked over 44 million morbidity and mortality records from four Australian states between 1st July 1999 and 31st December 2009 using probabilistic methods. The accuracy of the linkage was measured through a comparison with jurisdictional keys sourced from individual states. The extent of cross-border population movement between these states was also assessed.
  
  
  RESULTS
  Data matching identified almost twelve million individuals across the four Australian states. The percentage of individuals from one state with records found in another ranged from 3-5%. Using jurisdictional keys to measure linkage quality, results indicate a high matching efficiency (F measure 97 to 99%), with linkage processing taking only a matter of days.
  
  
  CONCLUSIONS
  The results demonstrate the feasibility and accuracy of undertaking cross jurisdictional linkage for national research. The benefits are substantial, particularly in relation to capturing the full complement of records in patient pathways as a result of cross-border population movements. The project identified a sizeable 'mobile' population with hospital records in more than one state. Research studies that focus on a single jurisdiction will under-enumerate the extent of hospital usage by individuals in the population. It is important that researchers understand and are aware of the impact of this missing hospital activity on their studies. The project highlights the need for an efficient and accurate data linkage system to support national research across Australia.
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. j.boyd@curtin.edu.au.
authors.forename: James H
authors.initials: JH
authors.lastname: Boyd
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. sean.randall@curtin.edu.au.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Randall
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. a.ferrante@curtin.edu.au.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Ferrante
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. jacbauer79@gmail.com.
authors.forename: Jacqueline K
authors.initials: JK
authors.lastname: Bauer
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. kevin.mcinneny@nhs.net.
authors.forename: Kevin
authors.initials: K
authors.lastname: McInneny
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. adrian.brown@curtin.edu.au.
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Brown
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. katrina.spilsbury@curtin.edu.au.
authors.forename: Katrina
authors.initials: K
authors.lastname: Spilsbury
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. m.gillies@curtin.edu.au.
authors.forename: Margo
authors.initials: M
authors.lastname: Gillies
authors.affiliation: Centre for Population Health Research, Faculty of Health Sciences, Curtin University, Bentley, 6102, WA, Australia. james.semmens@curtin.edu.au.
authors.forename: James B
authors.initials: JB
authors.lastname: Semmens
mesh_terms: D001315:Australia; D019091:Critical Pathways / Q000592:standards*; D006753:Hospital Records; D006760:Hospitalization; D006801:Humans; D016247:Information Storage and Retrieval; D007256:Information Systems; D008498:Medical Record Linkage / Q000379:methods; D009017:Morbidity; D014195:Travel