Impact of instructor professional background and interim retesting on knowledge and self-confidence of schoolchildren after basic life support training: a cluster randomised longitudinal study.

Introduction To increase the rate of bystander resuscitation, basic life support (BLS) training for schoolchildren is now recommended on a broad level. However, debate continues about the optimal teaching methods. In this study, we investigated the effects of a 90 min BLS training on female pupils' BLS knowledge and self-confidence and whether learning outcomes were influenced by the instructors' professional backgrounds or test-enhanced learning. Methods We conducted a cluster randomised, longitudinal trial in a girls' grammar school in Germany from 2013 to 2014. Pupils aged 10-17 years were randomised to receive BLS training conducted by either emergency physicians or medical students. Using a multiple-choice questionnaire and a Likert-type scale, BLS knowledge and self-confidence were investigated before training (t(0)), 1 week (t(1)) and 9 months after training (t(2)). To investigate whether test-enhanced learning influenced learning outcomes, the questionnaire was administered 6 months after the training in half of the classrooms. The data were analysed using linear mixed-effects models. Results The study included 460 schoolchildren. BLS knowledge (mean number of correct answers) increased from 5.86 at t(0) to 9.24 at t(1) (p<0.001) and self-confidence (mean score on the Likert-type scale) increased from 8.70 at t(0) to 11.29 at t(1) (p<0.001). After 9 months, knowledge retention was good (8.94 at t(2); p=0.080 vs t(1)), but self-confidence significantly declined from t(1) to 9.73 at t(2) (p<0.001). Pupils trained by medical students showed a slight but statistically significant greater increase in the knowledge at both t(1) and t(2), whereas instructors' background did not influence gain or retention of self-confidence. Retesting resulted in a marginally, non-significantly better retention of knowledge. Conclusions BLS training led to short-term gains in knowledge and self-confidence. Although knowledge was retained at 9 months after the training session, self-confidence significantly decreased. Interim testing did not appear to impact retention of knowledge or self-confidence. Medical students should be considered as instructors for these courses given their favourable learning outcomes and greater availability.