Threshold Decisions in Social Work: Using Theory to Support Practice

Decision making is an intrinsic and complex aspect of social work practice, requiring consideration of diverse but connected aspects. Decisions are often required as to whether a situation requires protective state intervention or whether it reaches the criteria for public or charitable services. Such instances of deciding whether or not a situation is ‘on one side of the line or the other’ are referred to in this article as ‘threshold judgements’. This article draws on experiences and material from a range of social work contexts to explore generalisable theory-informed understandings of ‘threshold judgements’ and ‘threshold decisions’ to develop knowledge and skills on this topic. The article outlines signal detection theory and evidence accumulation (‘tipping point’) theory and discusses these as ways to understand the key concepts underpinning threshold decisions in social work. We then argue that although these threshold concepts are a necessary part of decision making in social work, as in many other aspects of life, they are not sufficient. Operationalising such decisions requires some form of sense-making. Naturalistic decision making and heuristic models of judgement are discussed as frameworks for practice which seem to be useful in this context.