ALONE scale for Portuguese older adults: Translation, cultural adaptation, content validity, and face validity

Background: Loneliness among older adults is a significant public health problem that requires early detection for effective intervention. The ALONE scale is a brief (five items) and reliable tool that holds promise for clinical use. Objective: Translation, cultural adaptation, content validity, and face validity of the ALONE scale for Portuguese community-dwelling older adults ( ≥ 65 years). Methodology: This methodological study comprised three stages: (a) translation and cultural adaptation; (b) content validity assessment with 15 experts (content validity index, CVI); and (c) face validity assessment through semi-structured interviews with eight older adults. Results: Linguistic equivalence was achieved with the original ALONE scale. The items had strong content validity (CVI ≥ 0.8, average CVI of 0.97, universal agreement of 0.71, excellent kappa). Face validity assessment showed that the ALONE scale captures the feelings of loneliness, is useful, and is easy to understand and complete. Conclusion: The translated and culturally adapted ALONE scale shows content and face validity for assessing loneliness among Portuguese older adults in community settings.