Table 3 Item parameter estimates and fit statistics of GRM

  1. Mouth sores

0.45

−2.54

0.08

8.01

12.18

61.4

60

0.426

  2. Bad breath

0.53

−3.01

−0.68

4.31

7.29

75.8

77

0.517

  3. Trouble sleeping

1.17

0.00

1.58

3.16

4.41

68.7

59

0.181

  4. Difficult to say any words

1.11

0.81

2.65

4.87

6.33

46.2

45

0.423

  5. Concerned with other people think

1.40

−0.34

0.90

2.68

3.76

61.9

59

0.372

  6. Upset

1.98

0.07

1.24

2.77

3.81

51.4

45

0.236

  7. Argued with other children or your family

1.65

0.06

1.24

2.95

4.00

62.9

47

0.061

  8. Teased/called names by other children

1.34

0.17

1.55

2.83

3.69

57.9

57

0.445

  1. Bad breath

0.53

−3.01

−0.68

4.31

7.29

75.8

77

0.517

  2. Food caught between/in teeth

0.63

−5.39

−2.78

2.48

7.7

62.4

61

0.424

  3. Difficult to bite or chew food like apples, corn on the cob or steak

0.96

0.14

2.29

4.77

6.47

56.5

53

0.344

  4. Difficult to drink or eat hot or cold foods

0.94

0.35

1.97

4.09

5.1

72.6

59

0.110

  5. Irritable/frustrated

1.84

−0.13

1.00

2.34

3.35

89.1

58

0.005

  6. Upset

1.98

0.07

1.24

2.77

3.81

51.4

45

0.236

  7. Avoided smiling/laughing when around other children

1.58

0.66

1.87

2.97

3.9

59.3

49

0.149

  8. Asked questions about your teeth, lips, jaws or mouth by other children

0.95

0.18

2.3

4.91

6.07

56.5

51

0.276