Development and psychometric properties of a friendly dietary function assessment scale for home-dwelling people with dementia

Background: Mealtime difficulties related to cognitive functioning negatively impact a patient’s life during the various stages of dementia, and they typically cause a burden and stress on family caregivers. Most people with dementia live at home alone or are cared for by informal caregivers, typically their spouses or other family members. However, no suitable screening tools for home-dwelling patients with dementia have been developed, nor have measurements focused on executive and self-eating functions. This study aimed to develop and evaluate the psychometric properties of the Dietary Function Assessment Scale (DFAS) for community-dwelling persons with dementia. Methods: A mixed-method design was used to develop the instrument. Methods included a comprehensive literature review to identify the item pool and an expert panel to assess the initial item pool. We performed convenience sampling of 190 home-dwelling people with dementia for psychometrical evaluation. The psychometric properties tests included item and factor analyses, criterion-related validity testing, internal consistency reliability testing, and defining the optimal cut-off values. The study was conducted from 2018 to 2019. Results: Items were generated based on an extensive literature review and pre-existing scales related to mealtime and executive functions in persons with dementia. The S-CVI/Ave of the DFAS was 0.89. A Principal Component factor analysis demonstrated seven items, with a two-factor structure accounting for 56.94% of the total variance. The two extracted factors were Self-eating ability and Dietary executive function. The confirmatory factor analysis indicated a good model fit. The criterion-related validity was adequate (r = -0.528, p < 0.01). The reliability of Cronbach’s alpha internal consistency was 0.74, and McDonald’s Omega coefficient was 0.80; the optimal cut-off value of 13 points with an AUC of 0.74 was established to determine poor dietary functioning in persons with dementia. Conclusion: The DFAS was simple, user-friendly, and a valid and reliable instrument to assess dietary functioning in community-dwelling persons with dementia. This short scale can be helpful for caretakers, who can use it to identify the dietary needs of home-dwelling persons with dementia and improve their care and eating experience.