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Datasets

The CHeReL has a number of data collections linked in the Master Linkage Key (MLK) and regularly links other datasets on a project-by-project basis. Data collections contained in the MLK are listed below. Metadata and variable lists for each MLK data collection are found in the Data Dictionaries section below.

CHeReL Master Linkage Key

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. 

353 Million
18 Million
30
number of datasets

Admitted Patient Data Collection

Jul 2001 - Jun 2023
60,213,121 records

(updated quarterly)

Private hospitals until June 2022

Emergency Department Data Collection

Jan 2005 - Jun 2023
46,659,129 records

(updated quarterly)

Perinatal Data Collection

Jan 1994 - June 2023
2,724,305 records

45 and Up Study

Participants recruited 2008/2009
266,413 records

NSW Cancer Registry

Jan 1972 - Dec 2021
1,581,391 records

RBDM death registrations

Jan 1985 - Jun 2024
1,889,167 records

(updated quarterly)

RBDM birth registrations

Jan 1994 - Dec 2023 (and 1990-1993)*
3,435,842 records

*identifiers for these records may not be complete

Notifiable Conditions Information Management System

Jan 1993 - Apr 2024
6,094,800 records

Perinatal Death Review Database

Jan 2000 - Dec 2021
15,010 records

Mental Health Ambulatory Data Collection

Jan 2001 - Jun 2023
58,539,556 records

NSW ANZDATA

1963 - 2023
298,379 records

NSW Pap Test Registry

Jul 1996 - Jun 2017
15,075,884 records

Australian Early Development Census

2009,2012,2015,2018
391,732 records

NSW Ambulance

Jan 2005 - Jun 2024
14,641,914 records

BreastScreen NSW

Jan 1988 - Dec 2023
8,466,324 records

NSW Controlled Drugs Data Collection (CoDDaC)

1985 - May 2023
748,670 records

Non-admitted Patient Data Collection

Jul 2015 - Jun 2024
132,529,777 records

Cause of Death Unit Record File

Jan 1985 - Dec 2022
1,803,410 records
view all datasets

Admitted Patient Collection

Jul 2004 - Jun 2023
1,962,330 records

Cancer Registry

Jan 1994 - Dec 2021
46,634 records

Emergency Department Data Collection

Jul 2005 - Jun 2023
2,268,831 records

ACT Perinatal Data Collection

Jan 1997 - Dec 2021
100,731 records

Notifiable Diseases Management System

Jan 2000 - Dec 2023
352,273 records

ACT BDM death registrations

Jan 1985 - Jun 2024
54,550 records

ACT BDM birth registrations

Jan 1997 - Jun 2024
154,293 records

Australian Early Development Census

2009,2012,2015,2018
20,510 records

ACT Kindergarten Health Check

2014 - 2021
42,008 records

ACT ANZDATA

1963 - 2023
20,330 records

ACT Ambulance

2011 - Dec 2023
534,313 records
view all datasets

MLK Yearly QA (2024) Fixes

Oct 2024
view all datasets

For information on other frequently-linked datasets outside the MLK, see the additional datasets page.

view all datasets

Data dictionaries

The CHeReL has updated the format and contents of all variable lists. Please download and read the instructions before completing the variable lists.

For datasets that don't have a pre-existing variable list, please use the blank template below. You will find instructions on how to do this in the researcher instructions.

Please contact the CHeReL if you have any problems downloading or completing the variable lists.

Researcher Instructions
Blank Variable List Template

This collection records all admitted patient services provided by New South Wales Public Hospitals, Public Psychiatric Hospitals, Public Multi-Purpose Services, Private Hospitals, and Private Day Procedures Centres.

APDC data dictionary
APDC variable list

NSW Ambulance data collections contain operational information from the Computer Aided Dispatch (CAD) system, and also data documented by clinicians in the paper-based Patient Health Care Record (PHCR) and electronic medical record (eMR). Clinical information includes patient vital signs. NSW Ambulance datasets capture information for emergency and urgent episodes of care for NSW Ambulance patients who: were transported to a hospital; were left at a scene following clinician assessment; or, who died at the scene. NSW Ambulance clinicians respond to more than one million emergency and non-emergency cases every year.

NSW Ambulance Computer Aided Dispatch (CAD) data request form
NSW Ambulance Patient Health Care Record (PHCR) data request form
NSW electronic Medical Record (eMR) data request form

The NSW Registry of Births, Deaths and Marriages (RBDM) keeps a permanent record of all registered births.

Births data dictionary
Births variable list

The NSW Cancer Registry maintains records of people with cancer and reports on the impact of cancer in the community.

NSWCR data dictionary
NSWCR variable list
Changes for 2021 NSW cancer incidence and mortality

The Emergency Department collection provides information about patient presentations to the emergency departments of public hospitals in New South Wales

EDDC data dictionary
EDDC variable list

The NSW Mental Health Ambulatory Data Collection is dedicated to the assessment, treatment, rehabilitation or care of non-admitted patients. It may include mental health day programs, psychiatric outpatients and outreach services (e.g. home visits). The data records 'contacts' (as opposed to 'episodes of care') by clinicians to a patient.

MH-AMB data dictionary
MH-AMB variable list

Two datasets contain mortality information for deaths occuring in NSW: the Registry of Births, Deaths and Marriages (RBDM) death registrations and the Australian Coordinating Registry (ACR) Cause of Death Unit Record File (COD URF), which also includes Australian Bureau of Statistics (ABS) death registration data prior to 2006.

Mortality data dictionary
NSW RBDM Death Registrations variable list
COD-URF variable list

The NSW NCIMS is a register of diagnoses of certain infectious diseases and adverse events following immunisation, notified to the NSW Department of Health by laboratories, hospitals, medical practitioners, schools, and child care centres.

NCIMS data dictionary
NCIMS variable list

The NSW Pap Test Register collects data on women who have a pap test in NSW and contains details of the woman undergoing the test and test results including Pap tests, cervical histology tests or HPV DNA tests.

NSW Pap Test Register data dictionary
NSW Pap Test Register variable list

The NSW Perinatal Data Collection (formerly known as the Midwives Data Collection) is a population-based surveillance system covering all births in NSW public and private hospitals, as well as homebirths.

PDC data dictionary
PDC variable list

The Perinatal Death Review Database includes information on about 800 perinatal deaths per year. The information is obtained from confidential reviews carried out by the NSW Maternal and Perinatal Committee, which is a quality assurance committee appointed by the Minister for Health to review perinatal morbidity and mortality in NSW.

Perinatal Death Review Database data dictionary
Perinatal Death Review Database variable list

The Sax Institute's 45 and Up Study is the largest cohort study of healthy ageing in Australia, established as a national resource to enable world-class clinical, public health and health services research. More than 250,000 men and women aged 45 and over across NSW - about 10% of this age group - were recruited to the 45 and Up Study and will have their health followed over the coming decades.

Its large size gives the Study power to answer research questions quickly and it can address a diverse range of queries, even those relating to uncommon conditions and small population groups. Increased participation from certain groups, such as rural participants and those over 85, has been achieved by oversampling.

The Sax Institute actively encourages the use of the resource by individuals or groups provided ethical and scientific quality criteria are met.

The 45 and Up Study data dictionaries and application forms can be found at the 45 and Up Study site.

Please note, access to the 45 and Up Study data linked to other NSW data collections requires an application to both the CHeReL and the 45 and Up Study team. Data may only be accessed via the Secure Unified Research Environment (SURE). For more information or to discuss further, please contact us.

  

The ACT Admitted Patient Care (APC) data records all inpatient separations (discharges, transfers and deaths) from all public and private hospitals in ACT. Currently, data from Canberra Hospital (Public) and Calvary Hospital (Public) are included in the Master Linkage Key.

ACT APC data dictionary
ACT APC variable list

The ACT Registrar of Births, Deaths and Marriages (ACT BDM) keep a permanent record of all registered births.

ACT birth data dictionary
ACT birth variable list

The ACT Cancer Registry maintains records of people with cancer in the ACT and reports on the impact of cancer in the community.

ACT Cancer Registry data dictionary
ACT Cancer Registry variable list

The ACT Emergency Department Data Collection provides information about patient presentations to the emergency departments of public hospitals in the ACT. 

ACT ED data dictionary
ACT ED variable list

Two datasets contain mortality information for deaths occurring in the ACT: The Registry of Births, Deaths and Marriages (ACT BDM) death registrations and Australian Coordinating Registry (ACR) Cause of Death Unit Record File (COD URF). The ACR COD URF is linked by ACT Health and is available from 2006 onwards.  

ACT Mortality data dictionary
ACT BDM death registrations variable list
COD-URF variable list

The ACT Notifiable Diseases Management System (NDMS) is a register of the diagnosis of certain infectious diseases and conditions notified to ACT Health by laboratories, hospitals and medical practitioners in the ACT. These notifications are held by the Communicable Disease Control Section at the Health Protection Service.

ACT NDMS data dictionary
ACT NDMS variable list

The ACT Perinatal Data Collection (formerly known as the Midwives Data Collection) is a population-based surveillance system covering all births in ACT public hospitals, as well as homebirths. Currently, data from Canberra Hospital and Calvary Hospital (Public) is included in the Master Linkage Key.

ACT PDC data dictionary
ACT PDC variable list

The Australian Early Development Census (AEDC) is a population based measure of children’s development in their first year of full-time school. The AEDC datasets provide widespread coverage of this group - national participation has been in excess of 96 per cent in each Census undertaken, in 2009, 2012 and 2015.

The CHeReL is an approved linkage unit and as such has already been deemed to meet the minimum requirements for having capacity to undertake linkage and the procedures, protocols and infrastructure to maintain the privacy of AEDC data.

Information on how to apply for linked AEDC data and other resources, including the AEDC Data Dictionary and application forms, can be found through the AEDC website here

Please note that access to the AEDC data linked to other NSW data collections requires an application to both the CHeReL and the AEDC data custodians.

BreastScreen NSW is part of a national program which is jointly funded by the Commonwealth and state and territory government. It is the central data holder for the results of all mammograms that have taken place in NSW as part of this program. BreastScreen NSW collects information on breast screening services within the prgram for women aged 40 years and over in NSW.

BreastScreen NSW data dictionary
Breastscreen NSW variable List
BreastScreen NSW content data specification

The Australian and New Zealand Dialysis and Transplant Registry (ANZDATA) records the incidence, prevalence and outcome of dialysis and transplant treatment for patients with end stage renal failure. Data is collected by web based data entry as events occur and by circulation of printed survey forms for each patient annually to all dialysis and transplant units in Australia and New Zealand. Data collected includes patient demographics and treatment (dialysis or transplant) specific data as well as capturing events such as cancer and parenthood. There is voluntary participation by all physicians/surgeons involved in dialysis/transplant treatment in both countries. The data held in the CHeReL MLK only patients who have received renal replacement therapy in Australia. The ANZDATA data dictionary can be found on their website: https://www.anzdata.org.au/anzdata/services/data-management/data-dictionary/

The NSW Controlled Drugs Data Collection (CoDDaC) records details of authorities from the NSW Ministry of Health to prescribe or supply a Schedule 8 drug, including methadone and buprenorphine under the NSW Opioid Treatment Program (OTP), psychostimulants for the treatment of Attention Deficient Hyperactivity Disorder in children and adults, and Schedule 8 opioids for the ongoing management of chronic pain.  The CoDDaC includes data relating to patients and prescribers.  The data collection system for the CoDDaC is the NSW Electronic Recording and Reporting of Controlled Drugs (ERRCD) system.  ERRCD was implemented in September 2016 to replace the legacy Pharmaceutical Drugs of Addiction System (PHDAS).

CoDDaC - data dictionary
CoDDac - OTP Variable list
CoDDaC - Other S8 Drugs variable list
CoDDaC - Notified psychostimulant prescriptions – variable list

The ROD contains finalised legal actions within the NSW Criminal Justice System (eg. criminal court appearances, juvenile cautions, youth justice conferences, custody entries and exits). Using a process of deterministic matching of personal identifiers these contacts are linked to individuals. Linked unit record data from ROD is available for research purposes with approval. The NSW BOCSAR ROD Deed of Access form can be accessed here: (https://www.bocsar.nsw.gov.au/Documents/guidelines_and_form_to_access_unitrecord_reoffending_data.doc).

  

The Non-Admitted Patient (NAP) Data Collection is a patient unit record level collection that covers all NSW Health non-admitted patient services that have clinical and/or therapeutic content that warrants a note being made in the patient’s medical record.

NAP data dictionary
NAP data dictionary appendix
NAP variable list

ACT Ambulance data collections contain operational information from the Computer Aided Dispatch (CAD) system, and also data documented by clinicians in the paper-based Patient Health Care Record (PHCR) and electronic medical record (eMR). 

ACT Ambulance Computer Aided Dispatch (CAD) data request form
ACT Ambulance Patient Health Care Record (PHCR) data request form
ACT electronic Medical Record (eMR) data request form
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