The randomly subjects in the control group shall receive oral and written information and the experimental group used App for two months. Pre- and post- measures shall include: patient safety knowledge and culture and self-perceived capacity to enhance RCA or follow-up PSC. In the experimental group, data shall also collect on their previous experience with information and communication technologies, their rating of each App. The inter-group intervention effects shall calculate by univariate linear models and ANOVA, with the pre- to post-intervention differences as the dependent variables.