NASA uses a continuous risk management process to seek out new knowledge of spaceflight-induced risk to human health and performance. The evidence base that informs the risk assessments in this domain is constantly changing as more information is gleaned from a continuous human presence in space and from ongoing research. However, the limitations of this evidence are difficult to characterize because fewer than 700 humans have ever flown in space, and information comes from a variety of sources that span disciplines, including engineering, medicine, food and nutrition, and many other life sciences. The Human System Risk Board (HSRB) at NASA is responsible for assessing risk to astronauts and communicating this risk to agency decision-makers. A critical part of that communication is conveying the uncertainty regarding the understanding of the changes that spaceflight induces in human processes and the complex interactions between humans and the spacecraft. Although the strength of evidence grades is common in the academic literature, these scores are often not useful for the problems of human spaceflight. The HSRB continues to update the processes used to report the levels of evidence. This paper describes recent updates to the methods used to assign the level of evidence scores to the official risk postures and to the causal diagrams used by the HSRB.

NASA 使用持续的风险管理流程来寻找有关太空飞行对人类健康和表现造成的风险的新知识。随着从人类在太空中的持续存在和正在进行的研究中收集到更多信息，为该领域的风险评估提供信息的证据基础正在不断变化。然而，这一证据的局限性很难描述，因为只有不到 700 人曾在太空飞行，而且信息来自跨学科的各种来源，包括工程、医学、食品和营养以及许多其他生命科学。NASA 的人类系统风险委员会 (HSRB) 负责评估宇航员面临的风险并将该风险传达给机构决策者。这种沟通的一个关键部分是传达对太空飞行在人类过程中引起的变化以及人类与航天器之间复杂相互作用的理解的不确定性。尽管证据强度等级在学术文献中很常见，但这些分数通常对解决载人航天问题没有用处。HSRB 继续更新用于报告证据级别的流程。本文介绍了用于将证据评分级别分配给官方风险态势和 HSRB 使用的因果图的方法的最新更新。