Background
Methods
The chronic illness sample
The original standardization sample
Pediatric self-report item banks and potential additional items
Number of items | |||||
---|---|---|---|---|---|
Domain | Original item pool | New items considered | New items after dimensionality analysis | New items after DIF analysis and calibration | Enlarged item pool |
Anger | 6 | 5 | 5 | 4 | 9† |
Anxiety | 15 | 5 | 3 | 2 | 15†† |
Depressive symptoms | 14 | 1 | 1 | 1 | 14††† |
Pain interference | 13 | 7 | 7 | 7 | 20 |
Fatigue | 23 | 2 | 2 | 2 | 25 |
Physical functioning: upper extremity | 29 | 5 | 5* | 5 | 34 |
Physical functioning: Mobility | 26 | 3 | 3 | 1 | 27 |
Statistical analysis
Preliminary checks on the data
Checking dimensionality
Calibration—IRT parameter estimation for the new items
Creation and revision of short forms
Results
The new items
DIF between | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Item parameters | S-X2fit 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 |
DIF between | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Item parameters | S-X2fit 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 Pain Interference item bank:
| ||||||||||||
It was hard for me to be away from home because I had pain. | 2.14 | 0.36 | 0.8 | 1.63 | 2.18 | 118 | 88 | 0.020 | 12.6 | 0.027 | 10.2 | 0.070 |
It was hard to have fun with friends because I was in pain. | 2.79 | ?0.06 | 0.48 | 1.3 | 2.12 | 107 | 81 | 0.028 | 8 | 0.154 | 11.7 | 0.040 |
I needed help walking when I was in pain. | 2.18 | 0.4 | 1.04 | 1.87 | 2.35 | 84 | 80 | 0.358 | 0.9 | 0.970 | 3.4 | 0.640 |
I walked carefully when I was in pain. | 1.92 | ?0.41 | 0.1 | 1 | 1.65 | 171 | 107 | 0.001 | 8.1 | 0.149 | 4.1 | 0.531 |
I had so much pain I had to stop what I was doing. | 2.6 | ?0.07 | 0.53 | 1.61 | 2.27 | 82 | 83 | 0.524 | 4.6 | 0.472 | 10.7 | 0.058 |
My pain was so bad that I needed to take medicine to treat it. | 1.9 | ?0.21 | 0.28 | 1.08 | 1.74 | 112 | 101 | 0.211 | 5.5 | 0.356 | 9.9 | 0.077 |
It was hard to do things with my family because I had pain. | 2.79 | 0.08 | 0.61 | 1.77 | 2.33 | 75 | 72 | 0.388 | 3.4 | 0.647 | 8.3 | 0.138 |
Added to the Fatigue item bank:
| ||||||||||||
Being tired made it hard for me to remember things. | 1.56 | ?0.2 | 0.67 | 2.26 | 3.05 | 105 | 94 | 0.203 | 3 | 0.694 | 1.9 | 0.861 |
I felt tired even when I had not done anything. | 1.4 | ?0.46 | 0.46 | 1.87 | 3 | 105 | 102 | 0.396 | 4.6 | 0.469 | 6.2 | 0.284 |
DIF between | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Item parameters | S-X2fit 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 Upper Extremity item bank:
| ||||||||||||
I could pick up coins from a table. | 2.94 | -3.23 | -2.66 | -1.87 | 10 | 8 | 0.247 | 3.8 | 0.291†† | 2.9 | 0.406†† | |
I could wash my hair by myself. | 2.14 | -2.84 | -2.37 | -1.61 | 18 | 22 | 0.731 | 1.3 | 0.861† | 5.4 | 0.253† | |
I could put beads on a string.* | 1.95 | ?3.32 | ?3.04 | ?2.41 | ?1.56 | 30 | 23 | 0.151 | 6.3 | 0.283 | 5.9 | 0.212† |
I could comb my hair by myself. | 2.43 | ?3.25 | ?2.8 | ?2.59 | ?1.65 | 19 | 14 | 0.160 | 3.9 | 0.269†† | 5 | 0.286† |
I could thread a needle.* | 1.54 | -2.14 | -2.02 | -1.43 | -0.57 | 50 | 41 | 0.162 | 9.7 | 0.083 | 12.1 | 0.034 |
Added to the Mobility item bank:
| ||||||||||||
I could jump up and down. | 2.93 | -2.3 | -2.06 | -1.7 | -1.16 | 73 | 43 | 0.003 | 4.1 | 0.539 | 2.5 | 0.774 |
Not added to the Mobility item bank (DIF):
| ||||||||||||
I could get in and out of a chair on my own. | 3.46 | -3.06 | -2.79 | -2.38 | -1.78 | 32 | 16 | 0.010 | 3.3 | 0.657 |
24.6
|
0.001
|
Not added to the Mobility item bank (LD and DIF):
| ||||||||||||
I could run three miles without stopping. | 1.51 | -0.52 | 0.04 | 1.04 | 1.74 | 52 | 57 | 0.678 |
14.8
|
0.011
| 7.6 | 0.176 |