LAUSR

To investigate the role of specialised content knowledge in instructor training on the teaching and learning of basic life support (BLS) in secondary schools. Cluster randomised controlled trial. Data were collected in three Flemish secondary schools during physical education classes. Three secondary schools were randomly assigned to a 60-minute BLS instructor training without (one school, three teachers) or with (two schools, five teachers) a focus on recognising and addressing common errors. Knowledge of common errors in the performance of BLS and how to correct these is referred to as specialised content knowledge. Following instructor training, all teachers taught BLS lessons to different students. Teachers’ use of time and interactions were assessed by means of systematic observation. BLS performance was assessed individually and unannounced to students ( n = 294) one week following their training using a validated protocol. On average, specialised content knowledge teachers interacted more with their students compared to common content knowledge teachers (8 vs 3 teacher interactions per lesson to the class as a whole, 43 vs 31 teacher interactions per lesson to students individually). In addition, students taught by specialised content knowledge teachers achieved significantly higher BLS scores (66% vs 61%; p < .05). Overall, average BLS performance of students correlated positively with the amount of time reserved for hands-on practice, r(21) = .51; p < .05. Specialised content knowledge (i.e. recognising and addressing common errors) should be part of BLS instructor training courses.