Assessment of frailty in older adults: Psychometric properties of the Multidimensional Frailty Scale (MFS)

Frailty is increasingly recognised as a multidimensional construct. However, existing instruments assessing multidimensional frailty either show limited validity evidence or fail to adequately cover all the proposed theoretical dimensions. To address this gap, we recently developed the preliminary items of the Multidimensional Frailty Scale (MFS), a new instrument designed to assess physical, cognitive, affective, social and environmental frailty in older adults. This study sought to determine the definitive item set and to evaluate the psychometric properties of the final version. We conducted a cross-sectional observational study with 283 individuals. Participants completed the preliminary 51-item version of the MFS, together with other measures of related constructs and a sociodemographic questionnaire. Item analysis yielded a final 29-item version of the MFS. Confirmatory factor analysis supported a five-factor second-order model with excellent fit to the data. Internal consistency was high for all dimensions and the total scale. Convergent validity was supported by moderate-to-strong correlations between corresponding MFS and TFI dimensions. Similarly, the expected associations of the MFS with age, loneliness, life satisfaction and independence in activities of daily living provided validity evidence based on relations to other variables. Overall, the MFS has robust psychometric properties and constitutes a brief yet comprehensive instrument for assessing multidimensional frailty. Its hierarchical structure allows both global and domain-specific assessment, supporting more precise identification of frailty profiles. These features make the MFS suitable for use in both applied settings and research, which may contribute to earlier detection and better targeting of preventive strategies for older adults.