Data Notes for BCCDC’s COVID-19 BC Regional, Canadian and Global Epidemiology Application
This application visualizes COVID-19 data using interactive charts across BC regions, Canadian and international jurisdictions. For more BC data, please visit
BCCDC COVID-19 data page.
The main purpose of the tool is to provide Canadian and global context to BC COVID-19 statistics as well as to enable users to build custom visualizations.
These data notes outline the data sources and definitions of metrics used in the application. Please note that data are updated regularly and may change over time as corrections are made in the source data feeds.
Frequency of updates
Please note that this dashboard is updated 3 times a week on Monday, Wednesday and Friday afternoons. To understand the epidemic trajectory, trends over time are more meaningful than daily fluctuations.
Pre-selected groups of comparison jurisdictions
Graphs displayed in this application have been initially produced by BCCDC to inform the broader public health community and other stakeholders across BC. The pre-selected groups of comparison jurisdictions included in the application are based on frequently requested comparisons by the BC user community.
Definitions
7-day moving average:
an average daily value over the 7 days up to and including the selected date. The 7-day window moves – or changes – with each new day of data. It is used to smooth new daily case and death counts or rates to mitigate the impact of short-term fluctuations and to more clearly identify the most recent trend over time.
Case:
a lab-confirmed case of COVID-19 as reported by the jurisdiction of interest. Case counts are greatly influenced by the testing criteria and the amount of testing that is being done in a given jurisdiction. Doing more tests can lead to more cases being identified, but that doesn’t necessarily mean that the magnitude of the epidemic has changed – it’s important to consider case counts/rates in the context of testing rates and test positivity.
Counts:
the absolute number of new or cumulative cases or deaths in a given jurisdiction on a given day.
Cumulative:
total number of cases or deaths reported from the beginning of the pandemic up to the selected date for the jurisdiction of interest.
Date:
date when a case or a death was publically reported based on the test result coming back positive. This does not necessarily represent the actual number of people who got sick or died on that particular date, but rather the date of when health officials were notified. This is also not the same as the date when symptoms, if any, may have begun, which often would have occurred prior to testing. For testing data, the date may represent the date of collection or the date of result, depending on the jurisdiction. For BC, it refers to the date of test result.
Death:
a COVID-19 related death as reported by the jurisdiction of interest. Please note that there is some variability between jurisdictions in how COVID-19 deaths are identified and this may include both lab-confirmed cases as well as suspected cases. Trends in deaths tend to mirror trends in cases, but with a delay. Death data at the BC Health Service Delivery Area level is not presented in the app.
Hospitalization census:
the total number of patients in hospital due to COVID-19 on a given calendar date. In BC, hospital census includes any person admitted to a hospital for at least an overnight stay, or with a prolongation of hospitalization, for reasons directly or indirectly related to their COVID-19 infection. If the client remains in hospital for reasons unrelated to COVID-19, after being removed from isolation requirements, they are no longer considered "currently hospitalized" due to COVID. If a client is removed from isolation but remains admitted due to complications of COVID, they continue to be considered "currently hospitalized" due to COVID. Please note that there are some differences in how this definition is applied across BC Health Authorities; there may be some regional differences in reporting. Hospitalization census data at the BC Health Service Delivery Area level is not available in the app.
New daily:
new cases or deaths that were reported on a given day in the jurisdiction of interest. This metric does not include cases or deaths that were reported prior to the day in question.
Rate:
number of cases or deaths per 100,000 population or number of tests per 1,000 population. Different denominators are used because there are usually fewer cases and deaths per capita than tests performed. Rates are a better measure than counts to compare jurisdictions because it accounts for the population size differences between them.
Test positivity:
proportion of COVID-19 tests that are positive for COVID-19, expressed as percentage. This metric can be used to understand if a jurisdiction is doing sufficient testing relative to the size of its epidemic to catch enough cases to maintain epidemic control. The higher the test positivity, the greater the likelihood that many cases are being missed and there is widespread community transmission, making it more difficult to limit the spread of the virus. For consistency, we adopted the same thresholds and colour scheme as
Our World in Data
which is in turn based on
guidance
from the World Health Organisation that a test positivity rate of less than 5% for at least two weeks is one potential indicator that the epidemic is likely under control. For Canadian jurisdictions (excluding BC), please note that the current public dataset includes number of people tested, not number of tests conducted, in a given day. Therefore, the test positivity estimation may differ slightly from what is reported by provinces and territories.
Percent of population received at least 1 dose:
the share of the total population that has received at least one dose of the COVID-19 vaccine. This may not equal the share that are fully vaccinated if the vaccine requires two doses. If a person receives the first dose of a 2-dose vaccine, this metric goes up by 1. If they receive the second dose, the metric stays the same.
Percent of population fully vaccinated:
the share of the total population who has received all doses prescribed by the current vaccination protocol.
New daily number of vaccinations administered:
the daily number of COVID-19 vaccination doses administered, shown as the rolling seven-day average. Note that this is counted as a single dose, and may not equal the total number of people vaccinated, depending on the specific dose regime (e.g. people receive multiple doses).
Although every effort has been made to provide accurate information, the British Columbia Centre for Disease Control and the Provincial Health Services Authority make no representation or warranties regarding the accuracy of the information in the dashboard and the associated data, nor will they accept responsibility for errors or omissions. Data may not reflect the current situation, and therefore should only be used for reference purposes. Access to and/or content of this dashboard and associated data may be suspended, discontinued, or altered, in part or in whole, at any time, for any reason, with or without prior notice, at the discretion of the British Columbia Centre for Disease Control and the Provincial Health Services Authority.
Anyone using this information does so at their own risk, and by using such information agrees to indemnify the British Columbia Centre for Disease Control and the Provincial Health Services Authority and their content providers from any and all liability, loss, injury, damages, costs and expenses (including legal fees and expenses) arising from such person’s use of the information on this website.
Please direct questions and feedback to the BCCDC: Admininfo@bccdc.ca