Confirmatory factor analysis goodness of fit indices for the Dyspnoea-12
| Model* | χ2 | df | Comparative Fit Index† | Tucker-Lewis Index† | Root mean square error of approximation‡ |
| Bidimensional | 52.68 | 53 | 1.00 | 1.00 | 0.008 |
| Unidimensional | 369.68 | 54 | 0.91 | 0.89 | 0.175 |
χ2 test of model fit was non-significant (p<0.05) for the bidimensional model and significant (p<0.001) for the unidimensional model.
*Bidimensional model with physical (items 1–7) and affective (items 8–12) domains. Unidimensional with a single overall domain.
†Acceptable fit if >0.95, poor fit if <0.90, otherwise marginal.
‡Acceptable fit if <0.06.