Long time frames to detect the impact of changing COVID-19 measures, Canada, March to July 2020 Stockdale, Jessica E and Doig, Renny and Min, Joosung and Mulberry, Nicola and Wang, Liangliang and Elliott, Lloyd T and Colijn, Caroline, Eurosurveillance, 26, 2001204 (2021), https://doi.org/10.2807/1560-7917.ES.2021.26.40.2001204