Table 2. Rating scale diagnostics, reliability indices and visual inspection of probability curves for original and collapsed 4-point rating scale.
| Rating scale | Regular response frequency | Category thresholds | Outfit mean square | Person separation | Item separation | Probability curve | |
|---|---|---|---|---|---|---|---|
| FACTOR 1 | original | no | disordered | < 2.0 | 1.34 | 9.36 | 0 and 6 peak only |
| 4-point | improved | disordered | < 2.0 | 1.25 | 8.76 | 0, 1 and 3 peak | |
| FACTOR 2 | original | no | disordered | < 2.0 | 1.19 | 2.24 | 0, 4 and 6 peak |
| 4-point | improved | ordered | < 2.0 | 0.98 | 2.64 | all peak | |
| FACTOR 3 | original | no | disordered | < 2.0 | 0.99 | 20.17 | 0 and 6 peak only |
| 4-point | improved | ordered | < 2.0 | 0.84 | 5.47 | all peak | |
| FACTOR 5 | original | no | disordered | < 2.0 | 0.95 | 7.81 | 0, 4 and 6 peak |
| 4-point | improved | ordered | < 2.0 | 0.69 | 7.53 | all peak |