Towards a measure of joint verbal functional communication of a person with dementia and the communication partner: an exploratory study

Background and Objective: This study explored the feasibility and usefulness of a set of observer rated outcome measures for the joint verbal functional communication of people with dementia and their communication partners, in combination with a set of quantitative measures for the language ability of the person with dementia. We hypothesized that the joint verbal functional communication would at least remain stable, despite an expected progressive deterioration of language ability of the person with dementia.Research Design and Methods: This was an exploratory study with audio and video recordings of 13 dyadic conversations before, directly after, and three and six months after a communication intervention. Four dyads of a home-dwelling person with dementia and their primary informal caregiver were included. Proportion of speaking time as well as occurrence and repair of communicative breakdowns were included as measures for joint verbal functional communication. Lexical diversity, propositionality and complexity of utterances were included as measures for language ability. Results: We found evidence that lexical diversity of the persons with dementia decreased over time. By contrast, there was no evidence that the proportion of speaking time by the persons with dementia changed over time. Discussion and Implications: Our combination of measures has primarily been proven feasible and useful for assessing joint verbal functional communication in persons with dementia and their communication partner, and seems to have potential for measuring the impact of a communication intervention. We recommend expanding our measures and investigating them in a larger sample.