The Canadian Census Health and Environment Cohorts (CanCHECs) enable the creation of population-based linked data sets.Footnote 1 The CanCHECs combine census long-form respondents (or the National Household Survey respondents) with administrative health data (e.g., mortality, cancer, hospitalizations, ambulatory care, and mental health) and annual mailing address postal codes. These data can be used to examine health outcomes by population characteristics measured by the census long-form sample data or the National Household Survey data (e.g., income, education, occupation, language, ethnocultural diversity, immigrant status, or Indigenous identity). Environmental data can be integrated into the CanCHECs using the annual postal code file in order to examine the association between environmental exposure and a health outcome. There are seven CanCHEC cycles: 1991, 1996, 2001, 2006, 2011, 2016, and 2021. Individuals who appear in more than one CanCHEC can be identified using the CanCHEC Cycle Overlap data set. The exclusive purpose of this data set is to allow researchers who are pooling two or more CanCHECs to remove duplicate records for a given individual to prevent overcounting individuals and associated events. It is important to note that the CanCHEC Cycle Overlap data set cannot be used for any other purpose.
Check out the short video Canadian Census Health and Environment Cohorts (CanCHECs): Creation of a new health surveillance program for an overview of the 1991 to 2011 CanCHECs, with examples of how these data have been used in research.Footnote 2
The CanCHEC linkages were approved by Statistics Canada's senior management (Microdata linkage approval number 019-2019) and are governed by the Directive on Microdata Linkage.
Demographic, social and economic data
1991, 1996, 2001, 2006, 2016, and 2021 Census long-form surveys
The Census of Population is the primary source of socioeconomic data for specific population groups (e.g., First Nations people, Métis and Inuit, immigrants, language groups) and for detailed or small geographies.Footnote 3 The long-form questionnaire was sent to approximately 1 in 5 Canadian households for the 1991, 1996, 2001, and 2006 censuses and 1 in 4 Canadian households for the 2016 and 2021 censuses. This questionnaire complements the short-form questionnaire and aims to provide more detailed information about people in Canada by demographic, social and economic characteristics. Only individuals included in the census long-form sample data were eligible for inclusion in the CanCHECs.
2011 National Household Survey
The 2011 National Household SurveyFootnote 4 (NHS) was a voluntary survey that was sent to approximately 1 in 3 Canadian households. This questionnaire collected the following information: education, training and learning; families, households and housing; immigration and ethnocultural diversity; income, pensions, spending and wealth; Indigenous peoples; labour; languages; population and demography; society and community. Only individuals included in the 2011 NHS data were eligible for inclusion in the 2011 CanCHEC.
Health outcome data
Canadian Vital Statistics — Death database
The Canadian Vital Statistics — Death databaseFootnote 5 (CVSD) is an administrative survey that collects demographic and cause of death information annually from all provincial and territorial vital statistics registries on all deaths in Canada. Death data are received from the province or territory where the death occurred. Cause of death information is coded using the International Statistical Classification of Diseases and Related Health Problems (ICD). The CanCHECs include only the deaths for the cohort members (i.e., not all deaths reported in the CVSD) and the mortality follow-up period varies by CanCHEC cycle. Death data for Yukon are not available as of 2017.
Canadian Cancer Registry
The Canadian Cancer RegistryFootnote 6 (CCR) is a national, dynamic, population-based registry that includes information about each new primary cancer diagnosed in cohort members since 1992. The CanCHECs include only the incident cancer cases for the cohort members, i.e., not all incident cancer cases reported to the CCR; the cancer incidence follow-up period and the jurisdictional coverage both vary by CanCHEC cycle.
Discharge Abstract Database
The Discharge Abstract DatabaseFootnote 7 (DAD) includes administrative, clinical, and demographic information on hospital discharges (including deaths, sign-outs and transfers) for all provinces and territories, except Quebec. Some provinces and territories also use the DAD to capture day surgery. Only the 2006, 2011 and 2016 CanCHECs include DAD records. The data availability by fiscal year (April 1 to March 31) may vary by CanCHEC cycle.
National Ambulatory Care Reporting System
The National Ambulatory Care Reporting SystemFootnote 8 (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 are collected at time of service in the participating facilities from several jurisdictions. Only the 2006, 2011 and 2016 CanCHECs include NACRS records. The data availability by fiscal year (April 1 to March 31) may vary by CanCHEC cycle.
Ontario Mental Health Reporting System
The Ontario Mental Health Reporting SystemFootnote 9 (OMHRS) contains data on individuals receiving adult mental health services from participating hospitals in Ontario, as well as from three facilities in Newfoundland and Labrador and one facility in Manitoba. OMHRS includes information about mental and physical health, social supports and service use, as well as care planning, outcome measurement, quality improvement and case-mix funding applications. Only the 2016 CanCHEC includes OMHRS records; these span from April 1, 2006 to March 31, 2022 (based on the assessment reference date).
Mobility data
Historical postal codes
Income tax returns are the principal data source for the historical postal codes file. Postal codes from the mailing addresses provided by tax filers when submitting their T1 tax file were extracted and used 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.Footnote 10 In some cases, there are records with incomplete postal code information, e.g., for individuals who have left the country, or those who have not filed a tax form. An imputed postal codes file is available for researchers who require complete postal code histories.Footnote 11
| 1991 CanCHEC | 1996 CanCHEC | 2001 CanCHEC | 2006 CanCHEC | 2011 CanCHEC | 2016 CanCHEC | 2021 CanCHEC | |
|---|---|---|---|---|---|---|---|
| Data source | 1991 mandatory census long-form | 1996 mandatory census long-form | 2001 mandatory census long-form | 2006 mandatory census long-form | 2011 voluntary NHS | 2016 mandatory census long-form | 2021 mandatory census long-form |
| Number of cohort members | 2.6 million | 3.6 million | 3.5 million | 5.9 million | 6.5 million | 8.4 million | 8.7 million |
| Minimum age (years) of cohort members on census day | 25 | 19 | 19 | 0 | 0 | 0 | 0 |
| Years of available annual postal codesTable note a | 1981 to 2016 | 1981 to 2016 | 1981 to 2016 | 1981 to 2019 | 1981 to 2019 | 1981 to 2020 | 1981 to 2022 |
| Years of follow-up for mortalityTable note b | 1991 to 2016 | 1996 to 2016 | 2001 to 2016 | 2006 to 2019 | 2011 to 2019 | 2016 to 2021 | 2021 to 2022 |
| Years of follow-up for cancer incidenceTable note c, d, e | 1992 to 2015 | 1992 to 2015 | 1992 to 2015 | 1992 to 2015 | 1992 to 2015 | 1992 to 2021 | |
| Years of follow-up for hospital dischargesTable note f | 2000–2001 to 2016–2017 | 2000–2001 to 2016–2017 | 2000–2001 to 2021–2022 | ||||
| Years of follow-up for ambulatory careTable note g | 2002–2003 to 2017–2018 | 2002–2003 to 2017–2018 | 2002–2003 to 2021–2022 | ||||
| Years of follow-up for mental health outcomesh | 2006–2007 to 2021–2022 | ||||||
Table notes
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