Researchers are having a hard time explaining why Quebec had Canada's highest official COVID-19 death toll despite a relatively low number of excess deaths between March 2020 and October 2021.

A new study released today by the Canadian Medical Association Journal tried to answer that question but came up short.

The study says Quebec had 4,033 excess deaths during that period but reported 11,470 COVID-19 fatalities -- almost three times more. It's the biggest gap recorded in Canada during the pandemic.

Excess deaths refer to the degree to which observed deaths exceed expected deaths based on modelling from previous years.

Kimberlyn McGrail, author of the study, "Excess mortality, COVID-19 and health care systems in Canada," says she observed too many factors to offer any definitive answer.

Frederic Fleury-Payeur with Quebec's statistical institute says he thinks Quebec doctors included COVID-19 as a cause of death more liberally than doctors in other provinces did.

-- This report by The Canadian Press was first published on May 30, 2022.