Canadian Population Health Survey data linked to mortality, hospitalization and historical postal codes

Canadian Population Health Survey data linked to mortality, hospitalization and historical postal codes
The purpose of this record linkage project was to create a linked dataset that will allow researchers to analyze the behavioural, socioeconomic, and environmental factors along with the use of hospital services and health outcomes at the population level using the Canadian Community Health Survey (CCHS) data from the Annual Component and Focus Content Surveys.

The Data

Canadian Community Health Survey (Annual Component and Focus Content Surveys)

The Annual Component of the Canadian Community Health Survey (CCHS) collects cross-sectional information about the health, health behaviours and health care use of the non-institutionalized household population aged 12 or older. The survey excludes full-time members of the Canadian Forces and residents of reserves and some remote areas, together representing about 4% of the target population. CCHS annual cycles 1.1 (2000-2001), 2.1 (2003), 3.1 (2005), 2007 to 2017 were included in this linkage project.

The CCHS focus content surveys are designed to provide cross sectional, provincial level results on specific focused health topics. Five focus content files were included in this linkage project : the CCHS - Mental Health and Well-being (2002) and CCHS - Mental Health (2012)CCHS - Nutrition (2004 and 2015) and CCHS - Healthy Aging (2008/2009). The CCHS questionnaires are available on the Statistics Canada website or through your RDC Analyst. Non-confidential information about the CCHS is available through the data liberation initiative, through your local RDC Analyst, or can be requested through Centre for Population Health Data client services (statcan.hd-ds.statcan@statcan.gc.ca).Once approval to access the linked files has been granted, user guides, questionnaires and other confidential documentation will be accessible to approved researchers in the RDC.

Discharge Abstract Database

(1999/00 to 2017/18)

The Discharge Abstract Database (DAD) includes administrative, clinical and demographic information on hospital discharges (including in-hospital deaths, sign-outs and transfers) from all provinces and territories, except Quebec. Over time, the DAD has also been used to capture data on day surgery, long-term care, rehabilitation and other types of care. For this record linkage, the DAD files covering fiscal years from 1999/00 to 2017/18 were linked to the CCHS Annual and Focus surveys.

In the DAD, jurisdiction-specific instructions for collection of data elements evolve over time. Collection of each data element may be mandatory, mandatory if applicable, optional or not applicable. Collection requirements can vary by jurisdiction and by data year.

Researchers will find the listings of DAD data elements on the Canadian Institute for Health Information (CIHI) website under the heading "Data Elements" at the DAD Metadata website1. Please note that not all DAD data elements are included in the dataset used for this linkage project. The documents on the website include information on mandatory versus optional collection status for each data element by jurisdiction, which is key to understanding coverage of data elements in the DAD.

National Ambulatory Care Reporting System

(2002/03 to 2017/18)

The National Ambulatory Care Reporting System (NACRS) contains data for hospital-based and community-based ambulatory care including day surgery, outpatient and community-based clinics, and emergency departments. Client visit data is collected at time of service in participating facilities from several jurisdictions. NACRS data for fiscal years 2002/2003 to 2017/2018 were linked to the CCHS Annual and Focus surveys.

Researchers will find the listings of NACRS data elements on the Canadian Institute for Health Information (CIHI) website under the heading "Data Elements" at the NACRS Metadata website2. The documents on the website include "a comparative list of NACRS data elements for all data submission options, along with a brief description of each data element." As with the DAD, the status of a data element may vary due to service type and/or jurisdiction. Please note that not all NACRS data elements are available in the analytical file for this record linkage project.

Ontario Mental Health Reporting System

(2006/07 to 2017/18)

The Ontario Mental Health Reporting System (OMHRS) contains data for all individuals receiving adult mental health services in Ontario, in addition to some individuals receiving services in youth inpatient beds and selected facilities in other provinces starting in fiscal year 2006/07. Information regarding mental and physical health, social supports and service use, care planning, outcome measurement, quality improvement, and case-mix funding applications are all part of the OMHRS. For this record linkage, the OMHRS files covering the fiscal years from 2006/07 to 2017/18 were linked to the CCHS Annual and Focus surveys.

Researchers will find the listings of OMHRS data elements on the Canadian Institute for Health Information (CIHI) website under the heading "Data elements" at the OMHRS Metadata website3.

Canadian Vital Statistics Death Database

(2000 to 2017)

The Canadian Vital Statistics – Death Database (CVSD) is an administrative dataset that includes demographic and cause of death information collected annually from all provincial and territorial vital statistics registries on all deaths in Canada. Death data are received from the province or territory of occurrence of death event. Records eligible for record linkage were death events that occurred from January 1, 2000 to December 31, 2017 and these deaths were linked to the CCHS Annual and Focus surveys.

Cause-of-death information is coded using the version of the International Classification of Diseases (ICD) in effect at the time of death. Details about the variables contained on the file can be obtained in the CVSD Data Dictionary, available from your RDC analyst.

Historical Postal Codes

(2000-2016)

In Canada, income tax returns are submitted annually to the Canada Revenue Agency (CRA. The T1 Personal Master File (T1PMF), also known as the T1 General and Schedules, is a collection of the income tax returns shared by the CRA with Statistics Canada, and it provides income and demographic (e.g., date of death) information on tax filers in Canada. Every resident of Canada who earns taxable income is required to complete an income tax return, known as a T1 form, at the end of the year in which the income was received. Therefore, the T1PMF includes almost all individuals who filed an individual T1 tax return for the year of reference (i.e., some late filers may not be included) or those who received Canada Child Tax Benefits (CCTB) and their non-filing spouses.

The T1PMF is the principal data source for the Historical Postal Code file. Mailing address postal codes reported on these tax file were extracted to estimate a person's place of residence for that reference year. Note that for some tax filers, the mailing addresses used for filing T1 tax records may not be associated with their place of residence (e.g. P.O. Box, accountants' or lawyers' offices, parents' addresses for young adults, children's addresses for elderly parents). See Bérard-Chagnon4 for more information.

The postal code history of each person who responded to the CCHS Annual and Focus surveys was included in this linkage from 2000 to 2016 for each year that a postal code was available on the CRA files. Due to the nature of the data source, postal codes are not available for all CCHS respondents (e.g., non-tax filers do not have a postal code history) and due to the tax filing habits of Canadian, postal codes may not be available for all years for all respondents.

File structure, layout

Cohort

All variables from the CCHS Annual and Focus Content surveys share files are available for analysis. Please see appropriate documents and data dictionaries.

Analytical files

The DAD, NACRS and OMHRS are event based files meaning that there will be more than one record for a person who made contact with the health care system more than once during the period of interest. During the linkage process, each CCHS and focus content record was assigned a unique STC_ID that allows the researcher to identify individuals on the DAD, NACRS and OMHRS with multiple interactions in the same dataset, across datasets and within a fiscal year and across fiscal years. DAD contains 19 files, NACRS 16 files and OMHRS one file. In order to use the file as a person based file, the researcher must transform the data to include all hospital information for one person as one record (one row on the data file).

For the CVSD, one analytical file that includes all deaths from January 1, 2000 to December 31, 2017 for respondents of the all CCHS and focus content cycles is available.

One file includes all historical postal codes files for CCHS and focus content data year included in the linkage project.

Weights

New linkage weights available in July 2019.

Footnotes

1. DAD Metadata website.
2. NACRS Metadata website.
3. OMHRS Metadata website.
4. Bérard-Chagnon J (2017). Comparison of Place of Residence between the T1 Family File and the Census: Evaluation using record linkage. Demographic Documents. September 26, 2017 Catalogue no. 91F0015M – No. 13, Statistics Canada.