Table 3.
Dimension characteristics of the SUMD
| Dimension/index (number of items) | M (SD) | Missing values % | Item-internal consistency (min-max) | Item discriminant validity (min-max) | Floor % | Ceiling % | Alpha* | INFIT** (min-max) |
|---|---|---|---|---|---|---|---|---|
|
Model 1 scoring: ‘not applicable’ = ‘0’ | ||||||||
| Awareness of disease (3) |
55.3 (22.1) |
0.13 |
0.81–0.90 |
0.32–0.44 |
4.5 |
17.1 |
0.83 |
0.86–1.15 |
| Awareness of positive symptoms (3) |
47.2 (27.2) |
0.70 |
0.79–0.85 |
0.37–0.48 |
22.3 |
15.3 |
0.76 |
0.88–1.09 |
| Awareness of negative symptoms (3) |
47.5 (25.4) |
0.53 |
0.81–0.87 |
0.31–0.44 |
16.8 |
11.3 |
0.80 |
0.87–1.12 |
| Index (9) |
50.0 (20.0) |
0.45 |
NA*** |
NA*** |
NA*** |
NA*** |
0.85 |
NA*** |
|
Model 2 scoring: ‘not applicable’ = missing data | ||||||||
| Awareness of disease (3) |
56.20 (22.0) |
1.6 |
0.82–0.93 |
0.43–0.70 |
48.2 |
17.1 |
0.87 |
0.73–1.39 |
| Awareness of positive symptoms (3) |
59.83 (19.6) |
23.0 |
0.82–0.88 |
0.52–0.68 |
28.5 |
15.3 |
0.82 |
0.93–1.10 |
| Awareness of negative symptoms (3) |
57.45 (19.4) |
15.5 |
0.85-0.90 |
0.43–0.67 |
35.2 |
11.4 |
0.85 |
0.81–1.14 |
| Index (9) | 57.83 (17.8) | 13.4 | NA*** | NA*** | NA*** | NA*** | 0.85 | NA*** |
*Cronbach’s Alpha, **Rasch’s statistics, ***NA Not Applicable.
M (SD) mean (standard deviation); a higher score represents a higher level of unawareness.