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. 2021 Sep 24;79(2):148–157. doi: 10.1016/j.annemergmed.2021.09.424

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Natural cubic splines with 95% confidence intervals (CIs) and equally spaced knots were fitted through the weekly count of certified deaths in the EDs (red shading area for 2020 and blue shading area for 2019). Three waves were shown in gray shading.