Psychometric properties of the Tilburg Frailty Indicator in older Spanish people

Background: The Tilburg Frailty Indicator (TFI) is a 15-item scale. It diagnoses frailty in the elderly based on three domains: physical, psychological and social. A Spanish cross-cultural adaptation and its psychometric properties are presented here. Materials and methods: Independent, non-institutionalized >= 70 year-olds were recruited. The TFI structure was assessed with Kuder-Richardson (KR-20) and confirmatory factor analyses. Sperman's correlations (r(s)) with Timed Up-and-Go, Self-assessed-health, Fried criteria, Short Physical Performance Battery, Gerontopole Frailty tool, assessed convergent validity. Known groups' validity and test-retest reliability were tested. Results: Based on n = 856 participants, domain and total scale KR-20 were < 0.70. The social domain and certain physical items did not fit adequately. Most physical and total scaler(s) were 0.31-0.48. Social domain r(s) were < 0.30. The TFI differentiated frail and no-frail subjects, but test-retest variation was considerable. Discussion: TFI applicability at different social contexts and frailty stages are worth of additional study. Certain scale aspects should be reconsidered.