In both of the universities in which this study was conducted there are ethics committees which had been established for the purpose of determining the ethical appropriateness of pharmaceutical trials using humans; since our study involved only the use of a questionnaire and not an experimental drug, we did not apply for approval from either of these ethics committees. Instead, written permission to carry out the study was granted by the dean of the faculty of medicine and by the chief manager of university hospitals. In addition, all of the potential participants were fully informed about the aim and structure of the study. Furthermore, potential volunteers were all made aware that participation was strictly voluntary and that all of the answers they provide would be done so anonymously.