Purpose:Periodic diagnostic tests and continuous and intermittent monitoring are integral to critical care medicine. The focus of this article is understanding the impact of existing diagnostic technology, as well as that of new diagnostic technology.Data Synthesis:We use literature about gastric tonometry to illustrate eight steps for assessing the value of diagnostic technology.Methods:These steps focus on how the technology works in the laboratory, its range of uses and diagnostic accuracy, its impact on healthcare workers, the decision making process, and patient outcomes, as well as issues of access, cost, and application in your own setting.Conclusions:Awareness of the scope and quality of research evaluating new and existing diagnostic technology is central to modern critical care practice.