Master Linkage Key (MLK)
The Master Linkage Key is a system of continuously updated links within and between core health-related datasets in NSW and the ACT. Both person and family-based extractions are available, as are tailored linkage services using additional datasets.
Quality assurance checks are regularly carried out on the Master Linkage Key. For more information on our quality checks and procedures see the Quality Assurance page.
CHeReL Master Linkage Key
-
315 Million
records
-
18 Million
people
-
17
average links per person
NSW NSW data that contributes to the CHeReL Master Linkage Key
Jul 2001 - Mar 2022
56,367,528 records
(updated quarterly)
Private hospitals until June 2021
Jan 2005 - Mar 2022
42,710,229 records
Jan 1994 - Dec 2020
2,489,268 records
Participants recruited 2008/2009
266,513 records
Jan 1972 - Dec 2019
1,448,212 records
Jan 1985 - Mar 2022
1,751,133 records
Jan 1994 - Dec 2020 (and 1990-1993)*
3,148,862 records
*identifiers for these records may not be complete
Jan 1993 - Mar 2022
1,593,496 records
Jan 2000 - Dec 2020
14,127 records
Jan 2020 - Dec 2021
213,833 records
1963 - 2020
328,605 records
Jan 2001 - Dec 2021
53,212,631 records
Jul 1996 - Jun 2017
15,075,884 records
2009,2012,2015,2018
391,732 records
Jan 2005 - Mar 2022
12,667,625 records
Jan 1988 - Dec 2021
7,735,661 records
1985 - 2019
685,715 records
Jul 2015 - Mar 2022
99,065,468 records
Jan 1985 - Dec 2020
1,685,162 records
ACT ACT data that contributes to the CHeReL Master Linkage Key
Jul 2004 - Jun 2021
1,699,559 records
Jul 2005 - Jun 2021
1,979,523 records
Jan 1994 - Dec 2019
41,115 records
Jan 1997 - Dec 2019
90,225 records
Jan 2000 - June 2021
84,584 records
Jan 1985 - Jun 2021
46,394 records
Jan 1997 - Dec 2020
135,321 records
2009,2012,2015,2018
20,510 records
2014, 2015, 2016
15,124 records
1963 - 2020
17,674 records
2011 - 2020
373,750 records
Upcoming Upcoming data that contributes to the CHeReL Master Linkage Key
