areas. With guidance from National Academies’ (see Appendix A) and other advisory reports, 150 risks were identified. More recently, and after several iterations, the list was culled to the 45 risks that are the focus of the current BR (http://bioastroroadmap.nasa.gov).
The current set of risks and related research and technology questions were identified through an iterative process that included input from the discipline teams, the Bioastronautics Science Management Team, the Chief Health and Medical Officer, the Astronaut Office, flight surgeons, and NASA research management.
In the characterization of risks contained in the BR, risk assessment criteria included the determination of the likelihood of occurrence; the severity of consequences of each risk in terms of the crew’s health, safety, and ability to perform mission objectives; and the state of the mitigation strategy. Relative risk priorities were derived from that assessment. Each risk has a set of associated research and technology questions. The answers to these questions are intended to lead to (1) risk assessment and quantification, (2) the development of countermeasures to prevent or mitigate the deleterious effects of space flight, (3) an improved basic understanding of underlying processes, and (4) medical diagnostic and treatment capabilities. This risk-based approach was devised to enable the development of a more rigorous decision-making process for allocation and implementation of resources, risk prioritization, access to facilities, operational requirement implementation, and crew time, as well as for development of cost-effective countermeasures and the design and implementation of effective advanced life support technology.
The committee agrees that NASA’s decision to draw on expert opinion in identifying and ranking risks is a reasonable strategy, given the broad array of topics addressed in the BR and the need, in some cases, to characterize risks by extrapolation from current experience. However, the committee believes there are weaknesses in the current risk assessment process related to (1) lack of information regarding the quality of evidence that informs risk assessment, (2) the obscuring of risk that results from “lumping” both the risk and its associated mitigation into a single value, and (3) lack of a quantitative measurement of uncertainty related to the risk. These areas can, and should, be enhanced, and they are discussed in the sections leading to Recommendations 3.1, 3.2, and 3.3. These recommendations flow from an understanding that expert opinion in health care and the life sciences is influenced both by systematically derived data and by heuristics, or “rules of thumb,” that are derived from personal and group experience