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
-
323 Million
records
-
18 Million
people
-
18
average links per person
NSW NSW data that contributes to the CHeReL Master Linkage Key
Jul 2001 - Jun 2022
56,872,868 records
(updated quarterly)
Private hospitals until June 2021
Jan 2005 - Jun 2022
43,531,898 records
Jan 1994 - Dec 2021
2,588,584 records
Participants recruited 2008/2009
266,513 records
Jan 1972 - Dec 2020
1,516,385 records
Jan 1985 - Jun 2022
1,769,644 records
Jan 1994 - Dec 2021 (and 1990-1993)*
3,248,856 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 - 2021
278,589 records
Jan 2001 - Jun 2022
54,746,412 records
Jul 1996 - Jun 2017
15,075,884 records
2009,2012,2015,2018
391,732 records
Jan 2005 - Jun 2022
12,867,512 records
Jan 1988 - Dec 2021
7,735,661 records
1985 - 2019
685,715 records
Jul 2015 - Jun 2022
102,818,785 records
Jan 1985 - Dec 2020
1,685,162 records
ACT ACT data that contributes to the CHeReL Master Linkage Key
Jul 2004 - Jun 2022
1,820,284 records
Jul 2005 - Jun 2022
2,123,158 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 2022
49,053 records
Jan 1997 - Dec 2020
135,321 records
2009,2012,2015,2018
20,510 records
2014, 2015, 2016
15,124 records
1963 - 2021
18,963 records
2011 - Jun 2022
449,213 records
Upcoming Upcoming data that contributes to the CHeReL Master Linkage Key
