PBT determinations: Weight of evidence approaches and the number of PBTs in commerce

I. Weight of evidence Weight of evidence (WOE) is a widely used concept, particularly in the field of risk assessment. However, a recent study of how the concept is used in risk assessment found no clear and consistent definition (Weed 2005). The author, in fact, found that risk assessors use the concept in several different ways. Proponents of WOE assessment urge organizations to clearly define what is meant by WOE and how it is going to be used by scientists and decision makers.