Abstract

Research drawn from data contained in medical records is a common and immensely important means of scientific investigation in epidemiology and health services research. It provides valuable knowledge regarding risk factors for disease, the safety of pharmaceuticals and medical procedures, and the quality of medical care. Electronic information technology has greatly enhanced the capability of conducting research using medical records, but it has also generated increasing concern about invasions of privacy. Both practical and scientific considerations militate against soliciting consent for population-based observational research. Retrospective review of existing medical records, especially with large samples, poses insuperable barriers to locating human subjects in order to obtain their informed consent. When efforts are made to obtain informed consent for prospective research drawn from disease and treatment registries, mounting evidence has accumulated that substantial selection biases are introduced into the data, as those who consent are not necessarily representative of the population of relevant patients.