Table 2.
Item parameters and values for the SS X 2 fit index and LR DIF statistics for the potential new items for the anger, anxiety, and depressive symptoms scales
| DIF between | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Item parameters | S - X 2 fit index | Boys and Girls | Ages | |||||||||
| Item Stem | a | b 1 | b 2 | b 3 | b 4 | X 2 | d.f. | p | X 2 | p | X 2 | p |
| Added to the Anger item bank: | ||||||||||||
| I was angry when things didn’t go my way | 1.41 | −0.8 | 0.33 | 1.74 | 2.60 | 62 | 70 | 0.748 | 2.6 | 0.755 | 5.8 | 0.328 |
| I wanted to be alone because I was so angry | 1.92 | −0.51 | 0.39 | 1.56 | 2.64 | 62 | 61 | 0.428 | 1.3 | 0.932 | 3.5 | 0.621 |
| I was so mad I did not want to talk to people | 2.1 | −0.25 | 0.51 | 1.86 | 3.01 | 54 | 53 | 0.448 | 5.3 | 0.382 | 2.5 | 0.772 |
| I had a bad temper | 1.69 | −0.44 | 0.60 | 1.71 | 2.64 | 62 | 67 | 0.640 | 9.9 | 0.079 | 2.9 | 0.710 |
| Not added to the Anger item bank (DIF): | ||||||||||||
| I could not control my anger | 1.69 | 0.11 | 0.96 | 1.86 | 2.36 | 785 | 59 | 0.050 | 16.4 | 0.006 | 9.1 | 0.104 |
| Added to the Anxiety item bank: | ||||||||||||
| I felt too nervous to be with a group of kids my age. | 1.34 | 0.52 | 1.42 | 2.81 | 3.48 | 77 | 75 | 0.401 | 2.4 | 0.794 | 2.0 | 0.856 |
| I worried that something might happen to my parents or guardians. | 1.29 | −0.23 | 0.45 | 1.73 | 2.28 | 121 | 92 | 0.024 | 5.9 | 0.314 | 2.1 | 0.840 |
| Not added to the Anxiety item bank (DIF): | ||||||||||||
| I was too worried to sleep alone. | 1.34 | 0.93 | 1.79 | 2.65 | 3.32 | 83 | 60 | 0.026 | 3.8 | 0.576 | 25.1 | 0.001 |
| Not added to the Anxiety item bank (LD): | ||||||||||||
| I had trouble falling asleep because I was worried about something. | 1.65 | −0.13 | 0.72 | 2.14 | 2.91 | 78 | 74 | 0.343 | 7.6 | 0.176 | 3.0 | 0.707 |
| I was so nervous I felt sick. | 1.40 | 0.59 | 1.29 | 2.80 | 3.86 | 80 | 72 | 0.2332 | 0.6 | 0.989 | 4.1 | 0.537 |
| Added to the Depressive Symptoms item bank: | ||||||||||||
| I felt sad for no reason. | 1.65 | 0.41 | 1.19 | 2.36 | 3.31 | 82 | 70 | 0.160 | 7.2 | 0.124† | 4.9 | 0.427 |
Notes: The scale for the item parameters is set such that the distribution of emotional distress in the reference population (represented by the NC portion of the sample) is standardized, mean 0 variance 1, as is conventional for reporting IRT parameters. d.f. =5 for all DIF X 2 statistics except that marked with †, for which d.f. = 4. Values in bold indicate test statistics and p values that are significant at p < .05 after adjustment for multiple comparisons.