Canadian Chronic Disease Surveillance System (CCDSS)

Context-Specific Notes:

• *Many CCDSS measures, such as chronic condition incidence, were influenced by the COVID-19 pandemic. Changes in such measures may be driven by multiple factors, including (but not limited to) differences in healthcare seeking behaviour, the availability and use of healthcare services, as well as true changes in health status. As such, CCDSS measures should be used cautiously when making inferences about population health during the COVID-19 pandemic. For the purposes of interpreting the estimates in this data tool, the COVID-19 pandemic period is defined as fiscal years 2020–2021 to 2022–2023. This timeframe aligns with the World Health Organization’s declaration of COVID-19 as a public emergency of international concern from January 30, 2020, to May 5, 2023. Guidance for data users on examining the impacts of the COVID-19 pandemic on CCDSS measures during the pandemic period can be accessed below.

General Notes:

• Crude estimates are based on randomly rounded counts to an adjacent multiple of 5. Crude estimates represent the actual impact of the condition, but do not take into account differences in age distributions across years or between geographical areas. Crude estimates should not be used to compare data across years if there are significant changes in the age distribution of the population over time or between geographical areas with different age structures.
• Data suppression: Estimates are not reported when the counts are less than 10 or the coefficient of variation is greater than 33.3%.
• Due to periodic updates of the historical surveillance data, estimates for a particular condition and year may change over time, and may not be comparable to previous versions.

Provincial and Territorial Notes:

• Nunavut data are excluded before 2005–2006.
• Newfoundland and Labrador data are excluded before 2008–2009.
• Yukon data are excluded before 2010–2011.
• New Brunswick data were not available for 2021–2022, 2022–2023 and 2023–2024.
• The modernization of the Quebec billing system for fee-for-service medical services by the Régie de l’assurance maladie du Québec (RAMQ) in 2016 has resulted in a decrease in the entry of diagnostic codes in the fee-for-service medical services file. Data for 2016–2017 and subsequent years should therefore be interpreted with caution, as a slight underestimation is suspected.

Other Notes:

• These data were made possible through collaboration between PHAC and the respective provincial and territorial governments of British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador, Northwest Territories, Yukon, and Nunavut. No endorsement by the provinces and territories is intended or should be inferred. Provincial and territorial data were contributed to the CCDSS as of April 2025.