We examined differences in the knowledge and beliefs that exist among nurse researchers in the USA (n = 119) regarding informed consent and the use of data from patients' medical records. Using a mail survey, two domains of ethical knowledge and beliefs were assessed: the legal right to privacy and the moral right to privacy. More than half of the participants were very confident in their knowledge of institutional review board procedures, research ethics, informed consent, the legal right to privacy, and the moral right to privacy. In contrast, most rated themselves as uncertain about US federal research regulations and there was wide variation in knowledge about current federal guidelines. Those who were more confident in their knowledge of or had more practical experience with research ethics, were no more likely to answer correctly a question about current federal guidelines regulating the use of patient data from medical records than those who reported less confidence or experience.