Frailty Among Older African Migrants in Australia: Validation, Item and Domain‐Level Analysis of a Culturally Adapted Instrument

ABSTRACT Background Older migrants from Sub‐Saharan Africa (SSA) living in high‐income countries often face cumulative life‐course disadvantages that increase their risk of frailty and related adverse health outcomes. Despite this elevated risk, little is known about the specific health deficits contributing to frailty in this population or how these deficits interact to shape frailty severity. This study aimed to validate the factor structure of the Frailty Instrument for Sub‐Saharan Africa (FiSSA) among older SSA migrants in Australia and assess the relative contribution of key health domains to frailty severity. Methods We conducted a cross‐sectional survey among 205 SSA migrants aged ≥ 50 years living in Australia. Frailty was assessed using 15 deficits grouped into four domains: Physical, Psychological, Vision, and Socio‐emotional. We used confirmatory factor analysis (CFA) to evaluate the latent structure of FiSSA, item response analysis to examine deficit performance across the frailty continuum, and relative weight analysis (RWA) with 10 000 bootstrap replications to estimate domain contributions to frailty severity. Results The CFA supported the four‐factor model with acceptable fit (CFI = 0.94, TLI = 0.92, CMIN/DF = 2.91) and significant item loadings. Expected item scores demonstrated monotonic performance across the frailty continuum, with physical items showing the highest sensitivity. RWA indicated that the Physical domain contributed most to frailty variance (32.7%), followed by Socio‐emotional (25.5%), Psychological (21.8%), and Vision (20.1%). Conclusion FiSSA demonstrated strong construct validity among older SSA migrants in Australia, supporting its use as a culturally grounded multidimensional screening tool for early detection and targeted interventions in primary care and community screening contexts.