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.

Eight hundred and twenty-six laypersons between 40 and 70 years old participated in CPR training. Performance of five discrete skills was tested in a scenario format immediately afterward: assessing responsiveness, calling the emergency telephone number 911, delivering ventilations of adequate volume, demonstrating correct hand placement for compressions, and delivering compressions with adequate depth. Thirteen AHA-certified instructors assessed these five skills and rendered a global performance rating; sensored Resusci Anne manikins with SkillReporting software recorded ventilation and compression data.

Instructors' ratings of the ventilation skills were highly accurate; ratings of compressions were correct about 83% of the time; yet inadequate compression depth was rated adequate 55% of the time, and incorrect hand placement was rated adequate 49% of the time.

Instructors' judgments alone are not sufficient to determine learners' competence in performing compressions. Assessment, technology, and guidelines must be better aligned so that learners can receive accurate feedback.