Abstract

This paper examines the role of modality resources (e.g., “may”, “often”) in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in representing behavioral pathology focusing, in particular, on Attention Deficit Hyperactivity Disorder (ADHD). ADHD diagnosis requires reports of non-practitioners (e.g., carers and teachers); an effective understanding of behavioral descriptors by the lay community is thus of paramount importance. The study combines qualitative linguistic discourse analysis and a corpus approach to study the presence and functions of modality, adopting a Systemic Functional perspective towards language. The study argues that in the DSM-5 modality is an important linguistic resource for conveying clinical significance, inferred from graduations of recurrence and probability. However, adopting features of professional discourse in representing behavioral pathology for non-experts, especially when those resources are inherently evaluative, stresses the need of health literacy among the lay social community and accessibility in health communication materials, particularly when non-practitioners are involved in the diagnosis practice.