Research Article
Development of the 8-Item Phlegm Pattern Questionnaire (PPQ-8) Using Rasch Analysis
Table 5
Dimensionality results of the 8-item Rasch analysis.
| | Standardised residual variance | Eigenvalue (%) |
| | Total raw variance in observations | 17.339 (100) | | Raw variance explained by measures | 9.339 (53.9) | | Raw variance explained by persons | 3.724 (21.5) | | Raw Variance explained by items | 5.616 (32.4) | | Raw unexplained variance (total) | 8.000 (46.1) | | Unexplained variance in 1st contrast | 1.598 (9.2) | | Unexplained variance in 2nd contrast | 1.511 (8.7) | | Unexplained variance in 3rd contrast | 1.169 (6.7) | | Unexplained variance in 4th contrast | 1.070 (6.2) | | Unexplained variance in 5th contrast | 0.991 (5.7) |
|
|
The value in bold indicates an acceptable eigenvalue of the variance for unidimensionality (<2.0).
|
