Table 1 Comparisons of model fit for the ASI

General population (N = 282)

  (a) Original five-factor model

511.981

367

 < 0.001

0.037

0.029–0.045

0.938

0.932

4-factor correlations > 0.90

  (b) Three-factor model^a

500.910

347

 < 0.001

0.040

0.032–0.047

0.932

0.926

−

  (c) One-factor model^a

548.720

350

 < 0.001

0.045

0.038 –0.052

0.912

0.905

−

 (b) vs (c)

(b) better than (c)

(Δχ² = 41.695, Δdf = 3, p < .001)

Clinical population (N = 150)

 (a) Original five-factor model

437.586

367

.007

0.036

0.020–0.048

0.955

0.950

3-factor correlations > 0.90 and loading of item 8 not significant

  (b) Three-factor model^a

403.218

347

.020

0.033

0.014 –0.046

0.964

0.961

−

(c) One-factor model^a

451.269

350

 < 0.001

0.044

0.031–0.055

0.935

0.930

−

  (b) vs (c)

(b) better than (c) (Δχ² = 38.963, Δdf = 3, p < 0.001)