Xuxi Zhang

Table 2 Score distributions and internal consistency of the TFI (n=2250) TFI Population Mean score±SD Range % of Min * % of Max † 25 th % tile 50 th %tile ‡ 75 th %tile Cronbach alpha § Full TFI (15 items) Total 5.20±3.17 0 ‐ 14 5.0 0.2 3 5 7 0.74 Spain 4.64±2.88 0 ‐ 13 3.6 0.2 2 4 7 0.70 Greece 5.80±3.09 0 ‐ 14 3.1 0.3 4 6 8 0.72 Croatia 6.92±3.20 0 ‐ 14 1.5 0.8 4 7 9 0.75 The Netherlands 4.25±3.01 0 ‐ 13 10.1 0.5 2 4 7 0.74 The United Kingdom 4.47±2.91 0 ‐ 13 7.2 0.2 2 4 6 0.72 Physical domain (8 items) Total 3.00±2.14 0 ‐ 8 14.0 1.2 1 3 5 0.70 Spain 2.74±1.88 0 ‐ 8 11.7 0.4 1 2 4 0.60 Greece 3.01±2.08 0 ‐ 8 12.4 0.8 1 3 5 0.68 Croatia 4.24±2.19 0 ‐ 8 4.6 3.4 2 4 6 0.72 The Netherlands 2.39±2.08 0 ‐ 8 26.0 0.5 0 2 4 0.73 The United Kingdom 2.59±1.98 0 ‐ 8 17.4 0.5 1 2 4 0.67 Psychological domain (4 items) Total 1.18±1.07 0 ‐ 4 34.4 2.0 0 1 2 0.52 Spain 1.11±1.03 0 ‐ 4 35.5 1.8 0 1 2 0.49 Greece 1.68±1.16 0 ‐ 4 19.2 5.4 1 2 3 0.55 Croatia 1.47±1.06 0 ‐ 4 24.8 2.7 1 2 2 0.55 The Netherlands 0.81±0.97 0 ‐ 4 49.2 1.1 0 1 1 0.50 The United Kingdom 0.91±0.92 0 ‐ 4 41.4 0.2 0 1 2 0.38 Social domain (3 items) Total 1.01±0.89 0 ‐ 3 33.4 5.4 0 1 2 0.29 Spain 0.79±0.85 0 ‐ 3 45.0 4.0 0 1 1 0.33 Greece 1.10±0.86 0 ‐ 3 27.1 5.1 0 1 2 0.22 Croatia 1.20±0.89 0 ‐ 3 23.1 8.2 1 1 2 0.24 The Netherlands 1.05±0.95 0 ‐ 3 36.1 6.8 0 1 2 0.43 The United Kingdom 0.97±0.85 0 ‐ 3 34.2 3.4 0 1 2 0.33 TFI, Tilburg Frailty Indicator * Percentage of respondents with the lowest possible score (floor); † Percentage of respondents with the highest possible score (ceiling); ‡ Median. § A value of Cronbach alpha between 0.7 to 0.9 represented satisfactory internal consistency reliability 34 ; The value of Cronbach alpha ≥ 0.7 in bold. 86 Chapter 4