A technical analysis of scaling in rehabilitation team talk

•Pre-existing semantic structures are used as the basis for interactional scaling.•Primary and secondary scales interact with each other to specify dysphagia level.•Diagrams are helpful in illustrating scalar relations co-constructed in actual talk.•A combination of conventional and indexical approaches to meaning is beneficial. Based on an analysis of audiovisual data from multidisciplinary rehabilitation team meetings in Japan, this paper investigates how Japanese rehabilitation team members collaboratively negotiate decisions about dietary prescriptions when treating stroke patients suffering from dysphagia (difficulty swallowing). Dysphagia can be scaled by the level of patients’ swallowing capacity; the lower the level, the more elaborate food modification is required. The paper first conducts componential analysis to uncover semantic relations among a set of dysphagia diets. Next, the paper draws on occasioned semantics to systematically illustrate how such relations are realized in actual interactive talk. Analysis shows that members utilize the pre-existing semantic structures of dysphagia diets as the basis for achieving various interactional activities, such as categorizing types of food, achieving rhetorical effects, and evaluating the level of dysphagia. Moreover, analysis reveals that the use of scaling diagrams is helpful in illustrating scalar relations co-constructed in actual conversation and understanding the mechanism of regrading (up/downgrading) phenomena. The paper integrates ethnographic information regarding the use of dysphagia diets into the analysis of formulation practices in decision-making activities. In so doing, the paper explores the interplay between a culturally shared, scaled semantic system and the emergent structure of meaning in medical team talk.