This month CanadiEM features an article recently published in the Canadian Journal of Emergency Medicine (CJEM) that focuses on the assessment of CPR quality by instructors.1 Since instructors teaching CPR do not have access to objective measures of CPR quality (rate, depth, fraction), they must rely on subjective assessments.2 As outlined in this CanadiEM infographic, this study by Brennan et al. set out to determine whether experienced instructors (emergency department staff and senior residents) could …