This lower rate of adverse events in radiation medicine may be attributable to several things. First, technologies involved in radiation diagnosis and therapy have been advancing rapidly since World War II, and their safety has appreciably improved. Second, the group of health care workers that deal with radiation is small, highly trained, and very aware of the potential dangers. They tend to be particularly careful. Third, the existence of strict regulations early on in the development of the science created an atmosphere in which a high degree of attention is paid to safety in the use of ionizing radiation. The committee recognizes the contribution to safety that NRC regulations have made in the past. However, as discussed later in this report, it believes that this standard of safety can now be maintained through improving technology, professional guidelines, training requirements, and institutional quality assurance programs.
In summary, the comparison of relative risks of misadministrations in by-product radiation medicine to error rates and untoward events in other medical practice settings, as well as the comparison of disease and death rates with the risks of the therapeutic administration itself, help to some extent to place ionizing radiation use in a broader context. Despite the unavoidably tenuous nature of the comparisons, the information raised the question of whether adverse events in radiation medicine are sufficiently widespread or serious to warrant the current burdens of regulation now directed at the field.
In addition to the problem of adverse events and human error, issues of medical services provided when they are not needed (or may even be contraindicated) arise. Certain surgical procedures provide a dramatic illustration of the problem. In the late 1980s, researchers at the RAND Corporation worked with expert panels of physicians to develop "appropriateness indicators" for several major procedures and health services, including coronary artery bypass graft (CABG). Using those criteria, the researchers were then able to derive a rough estimate of the percentage of patients who underwent inappropriate surgery and died as a result (Winslow et al., 1988a, 1988b). Of 386 cases studied, 56 percent of the surgeries were deemed appropriate, 30 percent equivocal, and 14 percent inappropriate. If one were to assume that the risk-adjusted mortality rate for CABG is 2.45 percent and that 200,000 procedures are performed annually, then (all other things equal) nearly 690 deaths would occur each year solely from inappropriate CABGs performed (686 = 200,000 × 0.14 × 0.0245).
The committee sought similar information from the field of radiation medicine. Few, if any, studies appear to have been done in this area, however, and no