Assessment of BLS skills: optimizing use of instructor and manikin measures

The primary objective of layperson CPR training is to ensure that learners achieve minimal competence to provide aid that improves the odds of survival of victims of out-of-hospital sudden cardiac arrest. During CPR courses, pronouncement of a learner's competence typically depends entirely on judgments made by an instructor; yet previous research strongly suggests that these judgments - particularly of chest compressions - are not sufficiently precise or accurate to ensure valid assessments. Comparisons of instructors' subjective assessments with objective data from recording manikins provide one means of understanding the magnitude and type of instructor errors in assessment.