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
-
293 Million
records
-
17.8 Million
people
-
16
average links per person
NSW NSW data that contributes to the CHeReL Master Linkage Key
Jul 2001 - Sep 2021
53,994,935 records
(updated quarterly)
Private hospitals until June 2020
Jan 2005 - Sep 2021
41,228,407 records
Jan 1994 - Dec 2020
2,489,268 records
Updated Jan 2018
266,550 records
Jan 1972 - Dec 2018
1,393,065 records
Jan 1985 - Sep 2021
1,722,144 records
Jan 1994 - Dec 2020 (and 1990-1993)
3,148,862 records
Jan 1993 - Dec 2019
1,490,009 records
Jan 2000 - Dec 2016
12,626 records
Jan 1985 - Dec 2019
1,633,109 records
Jan 2001 - Jun 2021
51,428,037 records
1963 - 2020
328,605 records
Jul 1996 - Jun 2017
15,075,884 records
2009,2012,2015,2018
391,732 records
Jan 2005 - Sep 2021
12,224,089 records
Jan 1998 - Dec 2020
7,444,894 records
1985 - 2019
685,715 records
Jul 2015 - Sep 2021
90,866,776 records
ACT ACT data that contributes to the CHeReL Master Linkage Key
Jul 2004 - Jun 2021
1,699,559 records
Jan 1994 - Dec 2018
38,690 records
Jul 2005 - Jun 2021
1,979,523 records
Jan 1997 - Dec 2019
90,225 records
Jan 2000 - June 2020
80,399 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
