risk-focused analysis of organizational and cultural issues become a visible part of the BR process.

Recommendation 4.2—Conduct Periodic Assessment of Additional Risks from Lack of Resources and Use This to Make Decisions About Microgravity and Behavioral Research Support

The committee recommends that NASA perform regular, detailed assessments of the additional risks to the conduct of the President’s 2004 vision for space exploration posed by the lack of available resources to fully address the issues posed in the BR. This assessment should then be used to make early strategic decisions regarding issues such as, but not limited to, the following:

1. How to provide support for a microgravity research platform that will have the resources (crew time, up-mass, facilities, and power) for the large amount of work necessary to validate countermeasures; achieve Technology Readiness Level 7 for life support systems sufficiently early in the design phase to allow their integration into the overall vehicle; and demonstrate the utility of medical procedures in microgravity.

2. How to support the extensive behavioral research program that would be necessary to validate processes or countermeasures such as select-in–select-out criteria (both for individual crew members and for a composite crew), issues related to cultural diversity, crew interactions, and isolation or stress-induced hazards. These issues may well require long lead times to study adequately.

Recommendation 4.3—Use Bayesian Sequential Trials Approach and Hierarchical Random or Fixed Effects Methods to Address the Small Sample Size

Drawing on the findings of the Institute of Medicine report Small Clinical Trials: Issues and Challenges (IOM, 2001), the committee recommends the use of pooled data from Bayesian sequential trials techniques and hierarchical random or fixed effects methods to compensate for the small sample sizes associated with individual flights.