A new framework to identify and assess hidden assumptions in the background knowledge of a risk assessment

Abstract

A risk assessment has a more or less subjective nature, as the analyst needs to make assumptions, analyse data, use models, and so on, to produce risk-related knowledge of the phenomena of interest. This background knowledge that forms the foundation of a risk assessment can be more or less strong, implying that it needs to be taken into consideration when describing and communicating risks. To meet this challenge, different methods have been developed to evaluate and inform the decision-maker about the strength of the background knowledge. For all these methods to be fully informative, the content of the background knowledge needs to be of good quality, covering, for example, all the relevant assumptions. To identify all the relevant assumptions, however, is not a trivial task, and the risk of missing assumptions increases with the complexity of the situation of interest. Hidden assumptions, which are not considered or identified, may induce false confidence in the risk assessment, its results and recommendations. This paper suggests a framework, using a systems approach, to identify and assess the background knowledge, as a means to reduce the risk of missing critical knowledge and obtain a more complete background knowledge, on which risk can be assessed.