| Primary school students | Middle school students | DIF contrast | ||||||
---|---|---|---|---|---|---|---|---|---|
 | Difficulty | Point-biserial | Infit MnSq | Outfit MnSq | Difficulty | Point-biserial | Infit MnSq | Outfit MnSq |  |
Subscale of Depression (person separation reliability = 0.62 and 0.68) |  |  |  |  |  |  |  |  |  |
1. I hated my life | -0.39 | 0.74 | 1.36 | 1.39 | 0.14 | 0.72 | 0.97 | 0.96 | 0.53 |
2. I hated myself | -0.06 | 0.74 | 0.85 | 0.85 | 0.54 | 0.69 | 0.93 | 0.87 | 0.60 |
3. I felt that life was terrible. | -0.29 | 0.78 | 0.81 | 0.81 | 0.03 | 0.75 | 0.86 | 0.85 | 0.32 |
4. I felt like I was no good | -0.21 | 0.76 | 0.82 | 0.85 | -1.01 | 0.72 | 0.94 | 0.93 | 0.80 |
5. I could not stop feeling sad | -0.16 | 0.75 | 0.92 | 0.91 | 0.23 | 0.70 | 0.97 | 0.99 | 0.39 |
6. I did not enjoy anything | 0.97 | 0.71 | 0.95 | 0.98 | 0.17 | 0.59 | 1.08 | 1.21 | 0.80 |
7. There was nothing nice I could look forward to. | 0.12 | 0.69 | 1.29 | 1.38 | -0.09 | 0.63 | 1.26 | 1.33 | 0.21 |
Subscale of Anxiety (person separation reliability = 0.62 and 0.54) |  |  |  |  |  |  |  |  |  |
8. I felt like I was about to panic | -0.20 | 0.77 | 1.01 | 0.99 | -0.32 | 0.71 | 0.97 | 0.95 | 0.12 |
9. I felt terrified | -0.49 | 0.80 | 0.92 | 0.88 | -0.12 | 0.71 | 0.89 | 0.85 | 0.37 |
10. I felt scared for no good reason | -0.69 | 0.78 | 1.09 | 1.09 | -0.36 | 0.63 | 0.95 | 0.93 | 0.33 |
11. I could feel my heart beating | -0.29 | 0.77 | 1.02 | 1.06 | -0.04 | 0.67 | 1.06 | 1.04 | 0.25 |
12. I had trouble breathing | 1.19 | 0.69 | 0.99 | 1.02 | 0.68 | 0.58 | 1.03 | 1.02 | 0.51 |
13. My hands felt shaky | 0.05 | 0.73 | 1.00 | 1.02 | -0.59 | 0.64 | 1.04 | 1.03 | 0.64 |
14. I felt dizzy, like I was about to faint | 0.44 | 0.71 | 0.92 | 1.03 | 0.74 | 0.57 | 1.08 | 1.19 | 0.30 |
Subscale of Stress (person separation reliability = 0.71 and 0.75) |  |  |  |  |  |  |  |  |  |
15. I got upset about little things | -0.16 | 0.79 | 1.02 | 1.01 | -0.53 | 0.73 | 0.96 | 0.95 | 0.37 |
16. I was easily irritated | -0.63 | 0.79 | 1.06 | 1.05 | 0.11 | 0.68 | 1.01 | 0.98 | 0.74 |
17. I found myself over-reacting to situations | 0.20 | 0.76 | 0.99 | 0.97 | 0.24 | 0.68 | 0.96 | 0.98 | 0.04 |
18. I was easily annoyed | 0.08 | 0.82 | 0.76 | 0.72 | -0.23 | 0.75 | 0.82 | 0.81 | 0.31 |
19. I was stressing about lots of things | 0.27 | 0.78 | 0.93 | 0.89 | -0.09 | 0.73 | 0.88 | 0.88 | 0.36 |
20. I got annoyed when people interrupted | -0.45 | 0.74 | 1.28 | 1.30 | 0.05 | 0.63 | 1.21 | 1.26 | 0.50 |
21. I found it difficult to relax | 0.69 | 0.72 | 0.94 | 0.88 | 0.47 | 0.60 | 1.17 | 1.23 | 0.22 |