Ethics approval and consent to participate
Before completing the first questionnaire, all participants were briefed on the study through the website, to ensure they understood the purpose of the study. Informed consent was obtained online by asking participants to click on the agreement, since the survey was conducted anonymously. Participation was voluntary and the confidentiality of the respondents was maintained. All methods were carried out in accordance with the relevant guidelines and regulation. As an incentive, 50 randomly selected participants received a 500-yen (about 5 USD) gift card after completing the post-test questionnaire. This study was approved by the Research Ethics Committee of the Graduate School of Medicine of the University of Tokyo, Japan.