Extending beyond “strength of knowledge”: Introducing “strength of justification” judgments in risk assessment

In recent years, considerable efforts have been made to better incorporate knowledge aspects into risk assessment. A variety of methods have been proposed, drawing on diverse attributes and both qualitative and quantitative approaches and methods. A central concept in this development is the “strength of knowledge” (SoK), which evaluates the strength of the knowledge base underpinning probability and risk judgments. This paper critically examines the SoK concept and argues for methodological advancement by expanding the focus beyond the mere strength of the supporting knowledge to also encompass the quality of the transformation process from that knowledge into the final probability and risk judgments. To address this, a new concept – “strength of justification” (SoJ) – is introduced. SoJ integrates both the quality of the knowledge itself and the rigor of the transformation steps leading to the probability and risk judgments. By adopting the SoJ framework, the paper derives enhanced methods for characterizing individual uncertainty judgments, as well as overall risk descriptions, offering a more comprehensive approach to assessing and communicating risk.