Provisional weekly estimates of the number of deaths, expected number of deaths and excess mortality: Interactive Tool

Additional information

The dashboard presents data that are relevant for monitoring the impacts of COVID-19 on mortality in Canada. It includes updated adjusted (i.e. the estimated number of weekly deaths) and expected weekly death counts produced for the 2020 reference year, from the Canadian Vital Statistics: Death database (CVS:D). The CVS:D is an administrative survey that collects demographic and medical (cause of death)information from all provincial and territorial vital statistics registries on all deaths in Canada.

With this tool, data users can explore trends in excess mortality for each province and territory. Prediction intervals are also presented in the interactive charts.

The interactive tool allows users to examine excess deaths by comparing the adjusted number of weekly deaths to the expected number of weekly deaths.

To visualize the prediction intervals for the adjusted numbers of deaths on the graph, select "Lower 95% prediction interval of adjusted number of deaths" and "Upper 95% prediction interval of adjusted number of deaths" in the legend under the graph.

The quality of the weekly adjusted counts is largely contingent on the level of completeness of the data, that is, the extent to which all deaths have been reported to Statistics Canada. For this reason, only estimates for weeks where the level of completeness reaches 75% or more are shown. This threshold offers a compromise between the robustness and the timeliness of estimates. The level of completeness reaches 90% or more for almost all weeks, with a few exceptions. More information on these exceptions can be found in the footnotes for table 13-10-0784-01.

Although useful to signal potential new recent trends in regard to excess mortality, estimates based on weekly data with lower level of completeness should be used with caution as they were found to carry more uncertainty and be more sensitive to model assumptions (such as the choice of the reference period). Consequently, these estimates are subject to change noticeably in subsequent releases as the number of reported deaths increase for these weeks.

Definitions

• Standard table symbols
• Weeks are as defined in several epidemiological studies, including those of the United States Centers for Diseases Control and Prevention (CDC). CDC weeks start on a Sunday and end on a Saturday. They are numbered sequentially from 1 to 52 or 53 depending on the year. The first CDC week in a year ends on the first Saturday of January, provided it has at least four days in that calendar year. The first CDC week of a year may include a few days from the previous calendar year. Conversely, the first few days of a calendar year may be included in the last CDC week of the previous year. Since CDC weeks can overlap two months, they do not perfectly recreate calendar months or years.