08 April 2022

Study to assess the incidence of COVID-19 in Quebec - Updated with data from the week of March 31 to April 5, 2022

CIRANO has published an update of its exploratory study to estimate the incidence of COVID-19 cases in Quebec. This update integrates the data from the twelfth week of collection, which took place from March 31 to April 5, 2022, with a sample of 3000 respondents representative of the Quebec population and compares them to other collection weeks.

It should be noted that this study is spread over several consecutive weeks in order to monitor the evolution of the situation. The study uses both a direct sampling strategy and an indirect sampling estimation based on the network scale-up (NSS) method. Details of the methods are available in the CIRANO 2022s-03 working paper.


Twelfth week of collection (March 31 to April 5, 2022)


23,500 to 43,500 cases per day, depending on the estimation method used.
Increase in the incidence of cases relative to the previous week (statistically significant (p<0.1) for all estimators. Increased since the week ending March 24-29 (approximately +10,000 cases/day).
Increase in case incidence for all age groups (except 40-49 years). Statistically significant increase in the 18-29 and 50-59 age groups.
Some regional disparities:
  • Increase more marked this week in Western Quebec and Central Quebec regions.
  • The trend is to stabilize in the Northern and Eastern regions of Quebec.
5.7% of Quebecers were in isolation during the week ending March 31 - April 5,  a statistically significant increase from the previous week (3.8%).


This study is conducted by a team of researchers composed of David Boisclair (HEC Montréal), Roxane Borgès Da Silva (Université de Montréal and CIRANO), Vincent Boucher (Université Laval) Nathalie de Marcellis-Warin (Polytechnique Montréal and CIRANO), Pierre-Carl Michaud (HEC and CIRANO),  Ingrid Peignier (CIRANO) and Alexandre Pud'Homme (Université de Montréal).