Sample size
impaired vision
DISEASE
The sample size was estimated through a statistical power analysis with GPower 3.1.9.7 software, with effect size 0.25, alpha type I error of 0.05, power of 0.8, and 3 groups with 3 times of measurements. The estimated total sample size of all interventional groups was 57. The target population comprised undergraduate and postgraduate students studying in northern Taiwan. The inclusion criteria were over 20 years old, no existing disease, easily stimulated by light and audio, and not holding valid CPR or first aid certification within 2 years. The exclusion criteria were having impaired vision and hearing, undergoing CPR or first aid training, obtaining valid CPR or first aid certification.