Xuxi Zhang1, Siok Swan Tan1, Lovorka Bilajac2, Tamara Alhambra-Borrás3, Jorge Garcés-Ferrer3, Arpana Verma4, Elin Koppelaar5, Athina Markaki6, Francesco Mattace-Raso7, Carmen Betsy Franse1, Hein Raat8. 1. Department of Public Health, Erasmus University Medical Center, Rotterdam, The Netherlands. 2. University of Rijeka, Faculty of Medicine, Department of Social Medicine and Epidemiology, Rijeka, Croatia. 3. Polibienestar Research Institute - Universitat de València C/Serpis, Valencia, Spain. 4. Manchester Urban Collaboration on Health, Center for Epidemiology, Division of Population Health, Health Services Research and Primary Care, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom. 5. Rotterdam University of Applied Sciences, Research Centre Innovations in Care, Rotterdam, The Netherlands. 6. Alliance for integrated care, Athens, Greece. 7. Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands. 8. Department of Public Health, Erasmus University Medical Center, Rotterdam, The Netherlands. Electronic address: h.raat@erasmusmc.nl.
Abstract
OBJECTIVES: To assess the internal consistency, convergent and divergent validity, and concurrent validity of the Tilburg Frailty Indicator (TFI) within community-dwelling older people in Spain, Greece, Croatia, the Netherlands, and the United Kingdom. DESIGN: Cross-sectional study. SETTING: Primary care and community settings. PARTICIPANTS: In total, 2250 community-dwelling older people (60.3% women; mean age = 79.7 years; standard deviation = 5.7). METHODS: We assessed the reliability and validity of the full TFI as well as its physical, psychological, and social domains. Baseline data of the Urban Health Centers Europe project were used. The internal consistency was assessed with the Cronbach alpha. The convergent and divergent validity were assessed using Pearson correlation coefficients between the domains and alternative measures: the 12-item short-form, Groningen activity restriction scale, 5-item mental well-being scale of the 36-Item Short Form Survey, and the De Jong Gierveld loneliness scale. The concurrent validity was assessed by the area under the receiver operating characteristic curve with physically frail (Survey of Health, Ageing and Retirement in Europe-Frailty Instrument), loss of independence (Groningen activity restriction scale), limited function (Global Activity Limitation Index), poor mental health (5-item mental well-being scale of the 36-Item Short Form Survey), and feeling lonely (De Jong Gierveld loneliness scale) as criteria. RESULTS: The internal consistency of the full TFI was satisfactory with the Cronbach alpha ≥0.70 in the total population and in each country. The internal consistency of the psychological and social domains was not satisfactory. The convergent and divergent validity of the physical, psychological, and social domains was supported by all the alternative measures in the total population and in each country. The concurrent validity of the full TFI and the physical, psychological, and social domains was supported with most area under the receiver operating characteristic curve ≥0.70 in the total population and in each country. CONCLUSIONS AND IMPLICATIONS: The TFI is a reliable and valid instrument to assess frailty in community-dwelling older people in Spain, Greece, Croatia, the Netherlands, and the United Kingdom.
OBJECTIVES: To assess the internal consistency, convergent and divergent validity, and concurrent validity of the Tilburg Frailty Indicator (TFI) within community-dwelling older people in Spain, Greece, Croatia, the Netherlands, and the United Kingdom. DESIGN: Cross-sectional study. SETTING: Primary care and community settings. PARTICIPANTS: In total, 2250 community-dwelling older people (60.3% women; mean age = 79.7 years; standard deviation = 5.7). METHODS: We assessed the reliability and validity of the full TFI as well as its physical, psychological, and social domains. Baseline data of the Urban Health Centers Europe project were used. The internal consistency was assessed with the Cronbach alpha. The convergent and divergent validity were assessed using Pearson correlation coefficients between the domains and alternative measures: the 12-item short-form, Groningen activity restriction scale, 5-item mental well-being scale of the 36-Item Short Form Survey, and the De Jong Gierveld loneliness scale. The concurrent validity was assessed by the area under the receiver operating characteristic curve with physically frail (Survey of Health, Ageing and Retirement in Europe-Frailty Instrument), loss of independence (Groningen activity restriction scale), limited function (Global Activity Limitation Index), poor mental health (5-item mental well-being scale of the 36-Item Short Form Survey), and feeling lonely (De Jong Gierveld loneliness scale) as criteria. RESULTS: The internal consistency of the full TFI was satisfactory with the Cronbach alpha ≥0.70 in the total population and in each country. The internal consistency of the psychological and social domains was not satisfactory. The convergent and divergent validity of the physical, psychological, and social domains was supported by all the alternative measures in the total population and in each country. The concurrent validity of the full TFI and the physical, psychological, and social domains was supported with most area under the receiver operating characteristic curve ≥0.70 in the total population and in each country. CONCLUSIONS AND IMPLICATIONS: The TFI is a reliable and valid instrument to assess frailty in community-dwelling older people in Spain, Greece, Croatia, the Netherlands, and the United Kingdom.