Background
Methods
Subjects
Measures and procedure
Translation and back translation of the TAS-20
NEO-FFI
Factorial validity with exploratory factor analysis
Confirmatory factor analysis
Reliability
Construct validity
Convergent validity
Concurrent (criterion-related) validity
Effects of age and gender on alexithymia
Software and statistical significance
Results
Overall psychometric properties of the TAS-20 and NEO-FFI
Normative | Patient | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
n | min | max | mean | sd | n | min | max | mean | sd | T | df | p | |
TAS-20 | |||||||||||||
DIF | 2592 | 7 | 35 | 14.4 | 5.2 | 1635 | 7 | 35 | 19.7 | 6.4 | t29.3 | 4225 | <0.0001 |
DDF | 2640 | 5 | 25 | 14.3 | 3.7 | 1640 | 5 | 25 | 15.8 | 4.1 | t12 | 4278 | <0.0001 |
EOT | 2600 | 8 | 35 | 19.6 | 4 | 1639 | 8 | 32 | 19.9 | 3.9 | t2.6 | 4237 | <0.01 |
Total | 2465 | 23 | 83 | 48.3 | 8.9 | 1630 | 24 | 88 | 55.4 | 10.4 | t23.4 | 4093 | <0.0001 |
NEO-FFI | |||||||||||||
N | 2637 | 4 | 48 | 25.5 | 7.2 | ||||||||
E | 2596 | 2 | 44 | 25.4 | 6 | ||||||||
O | 2577 | 7 | 47 | 29.4 | 5 | ||||||||
A | 2560 | 6 | 48 | 30.6 | 5.2 | ||||||||
C | 2608 | 5 | 44 | 27.2 | 4.9 |
Statistical analyses
Factorial validity
Exploratory factor analysis
2-factor | 3-factor | 4-factor | 5-factor | |||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Normative | Patient | Normative | Patient | Normative | Patient | Normative | Patient | |||||||||||||||||||||
Items | I | II | I | II | I | II | III | I | II | III | I | II | III | IV | I | II | III | IV | I | II | III | IV | V | I | II | III | IV | V |
Standardized Coefficients | ||||||||||||||||||||||||||||
DIF | ||||||||||||||||||||||||||||
1 |
0.69
| 0.00 |
0.72
| -0.03 |
0.61
| 0.11 | 0.00 |
0.60
| 0.17 | -0.03 |
0.61
| 0.15 | 0.04 | -0.06 |
0.54
| 0.25 | -0.02 | -0.01 |
0.58
| 0.18 | 0.00 | 0.04 | -0.10 |
0.73
| -0.02 | 0.09 | -0.04 | -0.08 |
3 |
0.45
| -0.08 |
0.45
| -0.05 |
0.53
| -0.07 | -0.06 |
0.60
| -0.16 | 0.05 |
0.52
| -0.04 | -0.02 | -0.07 |
0.59
| -0.13 | 0.04 | -0.02 |
0.55
| -0.03 | 0.06 | -0.16 | 0.03 | -0.17 |
0.73
| 0.02 | 0.08 | 0.06 |
6 |
0.63
| -0.05 |
0.68
| -0.03 |
0.64
| 0.01 | -0.04 |
0.63
| 0.08 | 0.00 |
0.63
| 0.00 | -0.06 | 0.05 |
0.58
| 0.16 | 0.01 | -0.02 |
0.61
| 0.01 | -0.07 | 0.04 | 0.00 |
0.70
| 0.04 | 0.01 | -0.01 | -0.09 |
7 |
0.64
| -0.03 |
0.57
| -0.20 |
0.82
| -0.18 | 0.00 |
0.81
| -0.25 | -0.08 |
0.81
| -0.16 | 0.01 | -0.01 |
0.82
| -0.22 | -0.09 | -0.04 |
0.84
| -0.16 | 0.08 | -0.10 | 0.04 | 0.11 |
0.70
| -0.12 | -0.08 | 0.01 |
9 |
0.68
| -0.06 |
0.7
| -0.12 |
0.68
| 0.02 | -0.05 |
0.68
| 0.05 | -0.08 |
0.67
| 0.03 | -0.05 | 0.00 |
0.65
| 0.09 | -0.10 | 0.02 |
0.65
| 0.04 | -0.07 | 0.05 | -0.04 | 0.33 |
0.36
| 0.10 | -0.09 | 0.03 |
13 |
0.74
| 0.06 |
0.66
| -0.02 |
0.65
| 0.12 | 0.07 |
0.77
| -0.09 | 0.08 |
0.64
| 0.11 | 0.04 | 0.07 |
0.76
| -0.07 | 0.05 | 0.03 |
0.64
| 0.11 | 0.05 | 0.02 | 0.07 | 0.34 |
0.45
| -0.04 | 0.05 | 0.04 |
14 |
0.57
| -0.01 |
0.59
| 0.07 |
0.57
| 0.01 | 0.00 |
0.46
| 0.18 | 0.06 |
0.57
| -0.01 | -0.03 | 0.06 |
0.43
| 0.18 | 0.02 | 0.09 |
0.55
| 0.00 | -0.04 | 0.07 | 0.00 |
0.72
| -0.11 | 0.01 | -0.01 | 0.02 |
DDF | ||||||||||||||||||||||||||||
2 |
0.57
| -0.02 |
0.68
| 0.03 | 0.21 |
0.47
| -0.05 |
0.45
| 0.30 | -0.02 | 0.20 |
0.53
| 0.00 | -0.09 | 0.34 |
0.44
| 0.03 | -0.08 | 0.17 |
0.56
| -0.04 | 0.02 | -0.10 | 0.21 | 0.17 |
0.43
| 0.04 | -0.06 |
4* |
0.39
| 0.12 |
0.45
| 0.13 | 0.08 |
0.39
| 0.10 | 0.23 |
0.29
| 0.08 | 0.05 |
0.54
| 0.23 | -0.20 | 0.07 |
0.50
| 0.18 | -0.18 | 0.03 |
0.58
| 0.18 | -0.03 | -0.15 | 0.05 | 0.03 |
0.51
| 0.19 | -0.15 |
11 |
0.46
| -0.03 |
0.53
| 0.12 | -0.04 |
0.65
| -0.08 | 0.15 |
0.49
| -0.01 | -0.04 |
0.61
| -0.13 | 0.08 | 0.09 |
0.50
| -0.04 | 0.13 | -0.03 |
0.57
| -0.12 | 0.01 | 0.11 | 0.07 | 0.05 |
0.49
| -0.03 | 0.16 |
12 |
0.38
| 0.06 |
0.40
| 0.12 | -0.03 |
0.52
| 0.03 | -0.02 |
0.53
| -0.03 | -0.04 |
0.47
| -0.06 | 0.15 | -0.08 |
0.55
| -0.04 | 0.10 | -0.02 |
0.43
| -0.04 | 0.03 | 0.18 | 0.11 | -0.14 |
0.49
| -0.04 | 0.11 |
17 |
0.27
| 0.01 |
0.34
| 0.07 | -0.06 |
0.41
| -0.02 | -0.04 |
0.48
| -0.07 | -0.08 |
0.36
| -0.12 | 0.18 | -0.10 |
0.50
| -0.07 | 0.09 | -0.04 | 0.31 | -0.02 | -0.11 |
0.33
| -0.09 | -0.03 |
0.52
| -0.06 | 0.13 |
EOT | ||||||||||||||||||||||||||||
5* | 0.00 |
0.45
| -0.06 |
0.48
| -0.09 | 0.09 |
0.45
| -0.10 | 0.04 |
0.47
| -0.11 | 0.04 |
0.32
| 0.25 | -0.08 | -0.05 |
0.39
| 0.18 | -0.19 | 0.05 | 0.12 |
0.51
| -0.03 | 0.09 | -0.13 | -0.09 |
0.39
| 0.15 |
10* | -0.01 |
0.50
| -0.02 |
0.45
| 0.04 | -0.09 |
0.51
| 0.06 | -0.12 |
0.53
| 0.04 | -0.04 |
0.55
| 0.00 | 0.03 | -0.09 |
0.53
| 0.00 | 0.05 | 0.00 |
0.49
| 0.10 | -0.04 | -0.02 | 0.05 | -0.06 |
0.53
| -0.01 |
18* | -0.10 |
0.38
| 0.04 | 0.25 | -0.02 | -0.12 |
0.39
| -0.04 | 0.10 |
0.23
| -0.01 | -0.08 |
0.43
| -0.03 | -0.12 | 0.20 |
0.30
| -0.11 | 0.03 | -0.05 |
0.47
| -0.04 | 0.01 | -0.11 | -0.03 | 0.23 |
0.31
| -0.09 |
19* | -0.07 |
0.63
| 0.01 |
0.49
| -0.09 | 0.00 |
0.62
| 0.05 | -0.06 |
0.55
| -0.09 | 0.03 |
0.63
| 0.06 | 0.00 | -0.01 |
0.60
| -0.04 | -0.04 | 0.06 |
0.70
| 0.01 | 0.10 | -0.07 | 0.06 | 0.04 |
0.61
| -0.04 |
8 | 0.31 |
0.36
| 0.21 |
0.43
| 0.21 | 0.12 |
0.36
| 0.07 | 0.17 |
0.39
| 0.19 | 0.01 | 0.16 |
0.40
| 0.13 | -0.02 | 0.24 |
0.40
| 0.12 | -0.04 | -0.05 |
0.59
| 0.11 | 0.23 | -0.02 | -0.07 | 0.24 |
0.37
|
15 |
0.23
| 0.12 | 0.19 | 0.20 | 0.09 |
0.17
| 0.11 | -0.09 |
0.34
| 0.09 | 0.07 | 0.09 | -0.04 |
0.29
| -0.06 | 0.19 | -0.08 |
0.43
| 0.12 | 0.02 | 0.03 | 0.02 |
0.33
| 0.00 | -0.03 | 0.17 | -0.07 |
0.43
|
16 | 0.04 | 0.16 | -0.01 | 0.16 | -0.09 |
0.15
| 0.14 | -0.18 |
0.20
| 0.08 | -0.11 | 0.06 | -0.02 |
0.30
| -0.12 | 0.04 | -0.06 |
0.35
| -0.07 | 0.00 | 0.04 | 0.06 |
0.31
| -0.19 | 0.03 | 0.08 | -0.06 |
0.38
|
20 | 0.12 |
0.26
| 0.19 | 0.19 | 0.06 | 0.06 |
0.26
| 0.08 | 0.14 |
0.16
| 0.05 | -0.05 | 0.08 |
0.36
| 0.14 | -0.01 | 0.02 |
0.32
| 0.06 | -0.09 | 0.07 | 0.20 |
0.25
| -0.07 | 0.19 | 0.04 | 0.04 |
0.35
|
Correlations between factors | ||||||||||||||||||||||||||||
I | -0.04 | -0.13 | 0.64 | -0.01 | 0.61 | -0.13 | 0.63 | -0.07 | 0.23 | 0.66 | -0.09 | 0.09 | 0.61 | -0.19 | 0.25 | 0.21 | 0.71 | 0.65 | -0.05 | 0.17 | ||||||||
II | 0.02 | 0.04 | -0.02 | 0.20 | 0.01 | 0.12 | -0.13 | 0.22 | 0.23 | 0.53 | -0.18 | -0.04 | ||||||||||||||||
III | 0.26 | 0.25 | 0.35 | 0.00 | -0.06 | 0.06 | ||||||||||||||||||||||
IV | 0.23 | 0.26 |
Confirmatory factor analysis
2-factor | 3-factor | 4-factor | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Normative | Patient | Normative | Patient | Normative | Patient | |||||||||||||
item No. | DIDF | EOT | DIDF | EOT | DIF | DDF | EOT | DIF | DDF | EOT | DIF | DDF | EOT | NKI | DIF | DDF | EOT | NKI |
1 | 0.70 | 0.74 | 0.70 | 0.74 | 0.69 | 0.74 | ||||||||||||
3 | 0.47 | 0.46 | 0.47 | 0.46 | 0.47 | 0.46 | ||||||||||||
6 | 0.64 | 0.70 | 0.65 | 0.71 | 0.65 | 0.70 | ||||||||||||
7 | 0.65 | 0.60 | 0.67 | 0.62 | 0.67 | 0.62 | ||||||||||||
9 | 0.68 | 0.72 | 0.69 | 0.72 | 0.69 | 0.72 | ||||||||||||
13 | 0.74 | 0.67 | 0.74 | 0.68 | 0.74 | 0.68 | ||||||||||||
14 | 0.58 | 0.59 | 0.59 | 0.60 | 0.59 | 0.60 | ||||||||||||
2 | 0.56 | 0.67 | 0.68 | 0.75 | 0.67 | 0.73 | ||||||||||||
4 | 0.38 | 0.44 | 0.50 | 0.52 | 0.63 | 0.30 | 0.63 | 0.30 | ||||||||||
11 | 0.44 | 0.49 | 0.58 | 0.56 | 0.58 | 0.57 | ||||||||||||
12 | 0.36 | 0.36 | 0.45 | 0.44 | 0.45 | 0.45 | ||||||||||||
17 | 0.24 | 0.31 | 0.32 | 0.38 | 0.33 | 0.38 | ||||||||||||
5 | 0.41 | 0.48 | 0.41 | 0.48 | 0.47 | 0.31 | 0.53 | 0.39 | ||||||||||
8 | 0.30 | 0.40 | 0.30 | 0.40 | 0.67 | 0.65 | ||||||||||||
10 | 0.51 | 0.49 | 0.51 | 0.49 | 0.41 | 0.51 | 0.48 | 0.56 | ||||||||||
15 | 0.11 | 0.13 | 0.11 | 0.14 | 0.28 | 0.31 | ||||||||||||
16 | 0.14 | 0.12 | 0.14 | 0.13 | 0.18 | 0.18 | ||||||||||||
18 | 0.42 | 0.25 | 0.42 | 0.26 | 0.25 | 0.50 | 0.21 | 0.33 | ||||||||||
19 | 0.66 | 0.53 | 0.66 | 0.53 | 0.50 | 0.69 | 0.50 | 0.61 | ||||||||||
20 | 0.24 | 0.17 | 0.24 | 0.16 | 0.33 | 0.31 |
Normative | Patient | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Estimate of correlation | Estimate of covariance | Standard error of covariance | Critical ratio for covariance | Estimate of correlation | Estimate of covariance | Standard error of covariance | Critical ratio for covariance | |||||
2-factor | ||||||||||||
DIDF | ↔ | EOT | -0.035 | -0.011 | 0.009 | -1.3 | ns | -0.048 | -0.024 | 0.018 | -1.4 | ns |
3-factor | ||||||||||||
DIF | ↔ | EOT | -0.041 | -0.013 | 0.009 | -1.5 | ns | -0.077 | -0.039 | 0.019 | -2.1 | * |
DDF | ↔ | EOT | -0.011 | -0.002 | 0.005 | -0.4 | ns | 0.041 | 0.011 | 0.01 | 1.0 | ns |
DIF | ↔ | DDF | 0.709 | 0.203 | 0.017 | 12.0 | * | 0.804 | 0.404 | 0.034 | 11.8 | * |
4-factor | ||||||||||||
DIF | ↔ | DDF | 0.722 | 0.167 | 0.014 | 11.9 | * | 0.81 | 0.32 | 0.028 | 11.3 | * |
DIF | ↔ | NKI | -0.426 | -0.082 | 0.013 | -6.5 | * | -0.368 | -0.12 | 0.021 | -5.7 | * |
DIF | ↔ | EOT | 0.388 | 0.151 | 0.013 | 11.4 | * | 0.221 | 0.117 | 0.021 | 5.6 | * |
EOT | ↔ | DDF | 0.353 | 0.092 | 0.011 | 8.2 | * | 0.269 | 0.094 | 0.017 | 5.7 | * |
NKI | ↔ | EOT | -0.378 | -0.082 | 0.024 | -3.4 | * | -0.484 | -0.141 | 0.04 | -3.5 | * |
NKI | ↔ | DDF | -0.419 | -0.054 | 0.009 | -5.8 | * | -0.323 | -0.071 | 0.016 | -4.5 | * |
Normative | Patient | |||||
---|---|---|---|---|---|---|
2-factor | 3-factor | 4-factor | 2-factor | 3-factor | 4-factor | |
RMSR | 0.080 | 0.073 | 0.046 | 0.093 | 0.086 | 0.070 |
GFI | 0.915 | 0.933 | 0.956 | 0.912 | 0.926 | 0.942 |
AGFI | 0.894 | 0.915 | 0.942 | 0.891 | 0.907 | 0.923 |
TLI | 0.778 | 0.824 | 0.885 | 0.796 | 0.827 | 0.864 |
CFI | 0.802 | 0.845 | 0.904 | 0.819 | 0.848 | 0.886 |
RMSEA | 0.068 | 0.061 | 0.049 | 0.067 | 0.062 | 0.055 |
HI 90 | 0.071 | 0.063 | 0.052 | 0.070 | 0.065 | 0.058 |
LO 90 | 0.066 | 0.058 | 0.046 | 0.064 | 0.058 | 0.052 |
χ2 | 2,105.1 | 1,684.9 | 1,100.7 | 1,405.1 | 1,201.1 | 937.7 |
df | 169 | 167 | 159 | 169 | 167 | 159 |
χ2/df | 12.5 | 10.1 | 6.9 | 8.3 | 7.2 | 5.9 |
AIC | 2,187.1 | 1,770.9 | 1,202.7 | 1,487.1 | 1,287.1 | 1,039.70 |
BIC | 2,425.3 | 2,020.7 | 1,499.0 | 1,708.2 | 1,519.0 | 1,314.8 |
Reliability
Concurrent (criterion-related) validity of TAS-20 with NEO-FFI
N | E | O | A | C | |
---|---|---|---|---|---|
DIF | 0.52** | -0.17** | 0.03 | -0.28** | -0.24** |
DDF | 0.38** | -0.38** | -0.06* | -0.16** | -0.24** |
EOT | -0.06* | -0.08** | -0.48** | -0.16* * | -0.16** |
Total | 0.43** | -0.29** | -0.21** | -0.30** | -0.31** |
Effects of age on the TAS-20
scores in each gender group | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
male | female | |||||||||
mean | SD | mean | SD | S2 | df | mean square | F | p | ||
TAS | ||||||||||
total | gender(G) | 48.2 | 8.7 | 48.4 | 9.1 | 0.34 | 1 | 0.34 | 0 | ns |
age group(A) | 4021.4 | 5 | 804.3 | 10.35 | <10-9 | |||||
(G)*(A) interaction | 179.4 | 5 | 35.9 | 0.46 | ns | |||||
DIF | (G) | 13.8 | 5.0 | 15.0 | 5.3 | 309.4 | 1 | 309.4 | 12.01 | <0.001 |
(A) | 2467.3 | 5 | 493.5 | 19.16 | <10-18 | |||||
(G)*(A) | 179.1 | 5 | 35.8 | 1.39 | ns | |||||
DDF | (G) | 14.3 | 3.6 | 14.4 | 3.8 | 1.11 | 1 | 1.1 | 0.08 | ns |
(A) | 765.8 | 5 | 153.2 | 11.59 | <10-10 | |||||
(G)*(A) | 15.8 | 5 | 3.2 | 0.24 | ns | |||||
EOT | (G) | 20.1 | 3.9 | 19.0 | 3.9 | 376.3 | 1 | 376.3 | 24.89 | <10-6 |
(A) | 905.6 | 5 | 181.1 | 11.98 | <10-10 | |||||
(G)*(A) | 21.8 | 5 | 4.4 | 0.29 | ns |