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
-
196 Million
records
-
15.6 Million
people
-
15
average links per person
NSW NSW data that contributes to the CHeReL Master Linkage Key
Jul 2001 - Sep 2020
50,723,175 records
(updated quarterly)
Private hospitals until June 2019
Jan 2005 - Sep 2020
38,119,596 records
Jan 1994 - Dec 2019
2,396,727 records
Updated Jan 2018
266,750 records
Jan 1972 - Dec 2017
1,332,966 records
Jan 1985 - Sep 2020
1,666,237 records
Jan 1994 - Dec 2019
2,442,767 records
Jan 1993 - Dec 2019
1,490,009 records
Jan 2000 - Dec 2016
12,626 records
Jan 1985 - Dec 2018
1,577,461 records
1963 - 2016
223,374 records
Jan 2001 - Jun 2020
48,439,156 records
Jul 1996 - Jun 2017
15,075,884 records
2009,2012,2015,2018
391,732 records
Jan 2005 - Sep 2020
11,362,025 records
Jan 1998 - July 2020
7,287,655 records
1985 - 2019
685,715 records
ACT ACT data that contributes to the CHeReL Master Linkage Key
Jul 2004 - Jun 2020
1,571,475 records
Jul 2005 - Jun 2020
1,825,901 records
Jan 1994 - Dec 2017
36,399 records
Jan 1997 - Dec 2017
79,286 records
Jan 2000 - June 2020
80,397 records
Jan 1997 - Jun 2020
44,011 records
Jan 1997 - June 2020
132,232 records
2009,2012,2015,2018
20,510 records
2014, 2015, 2016
15,124 records
1963 - 2016
15,942 records
2011 - 2018
277,236 records
Upcoming Upcoming data that contributes to the CHeReL Master Linkage Key