Assessing housing accessibility issues for older adults in Japan: an expert panel approach to cross-cultural adaptation and content validity of the Japanese housing enabler

Accessible housing plays a crucial role in supporting aging in place, yet Japan lacks adequate tools for assessing housing accessibility among older adults. This study describes the process of translating and adapting the environmental component checklist of the Swedish Housing Enabler instrument for valid use in Japan. During translation to the Japanese language, technical terms and specifications were adjusted to match Japanese standards and guidelines. To validate the content of the instrument’s checklist for the environmental component, an expert panel including occupational therapists, architects, and care managers was used. Relevance in a Japanese housing context was rated for all items on a scale from 1 to 4 (higher = more relevant), and a content validity index (0–1) was calculated for each item. After consensus discussions, the expert panel suggested revisions, including removal and addition of items, to better capture the characteristics of Japanese housing and building design. A final checklist of 261 items for the Japanese Housing Enabler was suggested. While 15 items were removed due to their lack of relevance to Japanese housing, 115 items were added. More than 90% of the items had a content validity index that exceeded the recommended threshold for relevance (≥ 0.78). Although the study results support the cultural relevance and content validity of this new instrument for assessing housing accessibility in Japan, the large number of items may compromise its feasibility. Aspects such as feasibility, criterion-related validity, and interrater reliability require investigation.