Psychometric adequacy of the persian adapted version of the tilburg frailty indicator (P-TFI)

Abstract

Abstract Background Frailty is identified as the primary goal of preventing the various consequences. The present study aimed to assess validity and reliability of the Persian adapted version of the Tilburg frailty indicator (TFI) in Iran. Method This cross-sectional study included three phases of translating the indicator to Persian, assessing the face and content validity, completing the P-TFI by older people, who helped assess the reliability and construct validity. For construct validity, convergent and divergent validity were used. It was expected that the TFI domain scores would show the highest correlations with their related measures of frailty (convergent construct validity) and the lowest correlations with measures of the other domains (divergent construct validity). The study population consisted of 400 older people, selected from six health care centers. Results The mean age of the participants was 69.05 ± 7.28 years and the majority of the participants were married woman with less than a high school education. The total mean score of TFI was 8.26 ± 1.80, and 42.75% was classified as frail. The test-retest reliability was 0.88 for the total scale, 0.80 for physical, 0.65 for psychological, and 0.81 for social domains. The mean score of frailty and its dimensions (physical, psychological, and social) varied from 4.35 ± 1.78, 1.81 ± 1.33, 1.69 ± 0.73, and 0.86 ± 0.61, respectively. The total score of the TFI was correlated with each alternative measure and the convergent validity was proved. Further, the kappa values ranging from 535 to 0.967 were significant and test- retest reliability for total, physical, psychological, and social dimension were 0.88, 080, 065, and 081, respectively. Further, the convergent or divergent validity is being discussed for clarity. Conclusion The Persian version of the TFI is valid and easy scored tools among Iranian’s older people.