Psychometric validation of the Portuguese ALONE scale and analysis of factors associated with severe loneliness in a sample of community-dwelling older adults

OBJECTIVES: Severe loneliness poses a significant risk to older adults' health and quality of life. This study assessed the psychometric properties (reliability and validity) of the Portuguese version of the ALONE scale in community-dwelling older adults and explored the scale's associations with sociodemographic, social isolation, depression, life satisfaction, and daily functioning. METHOD: A descriptive, correlational study was conducted with 285 Portuguese older adults. The questionnaire included sociodemographic and health data, the ALONE scale, Social Isolation Scale (SIS), Satisfaction with Life Scale (SWLS), Geriatric Depression Scale (GDS-15), UCLA Loneliness Scale (UCLA-16), and Lawton and Brody IADL Scale. Analyses included confirmatory factor analysis, internal consistency, group comparisons, correlations, and logistic regression. RESULTS: The confirmatory factor analysis supported a unidimensional model with satisfactory fit indices and internal consistency (α = 0.743). Severe loneliness correlated positively with social isolation and depression and negatively with life satisfaction and daily functioning. Participants experiencing severe loneliness were likely older, female, living alone, socially isolated, depressed, and dependent in daily activities. Significant predictors included social isolation (OR = 0.806) and depression (OR = 1.131). CONCLUSION: The ALONE scale demonstrated validity and reliability for assessing loneliness in older adults, making it a suitable, efficient tool for clinical practice.