Purpose of study: This study is aimed to assess the effectiveness of E-learning and European Resuscitation Council (ERC)  Basic Life Support (BLS) training with audiovisual feedback (AVF) for acquiring cardiopulmonary resuscitation skills. 
Methods: We included 596 first year medical students during 2016-2017 per 4 hour courses. All students completed the ERC Course System (CoSy) E-learning before the hands-on session. Students’ skills were assessed before and after the training for chest compressions depth, frequency, effectiveness and they completed an MCQ. Compressions had to meet the frequency of 100-120/min, depth of 5-6 cm with adequate hand position. Overall performance time was 3 minutes. Two instructors per candidate assessed the algorithm. Data was collected via ZOLL AED Plus (AVF) on Little Anne manikins. Effectiveness refers to BLS algorithm competence and skills in chest compressions and ventilations. Results were transformed into uniform numeric values. 
Results: At E- learning students gained 8,58  ± 1,80 points out of 10. Practical skills were in 62,78 ± 4,66 points out of 70. MCQ was 19,10 ± 0,58 out of 20 points. Overall points were 71 - 98 (90,46 ± 5,08). The effectiveness was 0 before the course at 77% of students, four students had over 50% of success. The effectiveness before the course was 0-94,79% (5,30 ± 16). The end-of-course effectiveness was 81,66%. Three thirds of students had 39,27% of effectiveness before training which changed to 91,91% at the end. The difference improved in compression depth 0,39 vs. 0,29 and in frequency 10,26 vs. 6,65. 
Conclusion: The updated CoSy with the use of E-leaning and the availability of AVF at BLS courses in this study demonstrated high efficiency in gaining required knowledge and underlined the significant importance that skills during hands-on sessions should be trained under instructor supervision and with AVF.

4 - The effectiveness of European Resuscitation Council Basic Life Support training with the use of audiovisual feedback and E-learning