Ethical issues in registry research: in-hospital resuscitation as a case study.

RESEARCH BASED ON REGISTRY STUDIES involves significant ethical issues. Using detailed information about one registry concerning in-hospital resuscitation, we present issues concerning informed consent, access to identifiable medical information, and benefit for participants. In addition, multiple methodological difficulties have indirect implications for the ethical conduct of registry research, including consensus about variable definitions, validity and reliability for clinical decisions, sample sizes, and sources of data. Both direct and indirect ethical issues are examined from the viewpoint of accepted regulations and codes regarding ethical conduct of research; specific examples of more or less ethical solutions to the problems are presented from published research.