Table 2 Univariate analysis for PCS and MCS of the SF-12v2 (n = 158)

Parent’s age

152

 Under 30 years

12

53.5 (5.9)

Reference

35.9 (15.7)

Reference

 30 to 40 years

80

54.7 (8.7)

1.23

41.9 (11.3)

5.97

 40 years or over

60

52.9 (8.7)

−0.59

43.3 (11.3)

7.37**

Parent’s qualification

147

 11 or 12 years of school

27

53.2 (7.9)

Reference

41.8 (13.2)

Reference

 TAFE/Technical certificate

29

53.6 (9.3)

0.40

41.2 (9.0)

−0.57

 University degree

91

54.4 (8.4)

1.14

42.0 (12.1)

−0.23

Maternal work status

147

 Full-time homemaker

64

55.1 (8.1)

Reference

42.7 (11.3)

Reference

 Part-time employment

37

50.4 (9.4)

−4.69**

42.4 (11.9)

−0.32

 Full-time employment

46

55.7 (7.5)

0.57

40.8 (11.2)

−1.86

Number of siblings

156

 0

36

54.3 (8.1)

Reference

37.4 (13.8)

Reference

 1

64

54.4 (7.5)

0.07

41.9 (11.3)

4.47*

 2 or more

56

52.9 (9.9)

−1.41

45.0 (9.6)

7.56**

Child order

156

 The first child

72

54.4 (7.9)

Reference

40.2 (11.7)

Reference

 Laterborn

84

53.3 (9.1)

−1.02

43.5 (11.4)

3.24*

Child’s age

158

 Under 1.5 years

24

53.3 (10.0)

Reference

39.8 (13.2)

Reference

 1.5 to 7 years

69

54.6 (7.6)

1.31

42.4 (12.4)

2.63

 7 to 13 years

40

52.7 (9.8)

−0.63

43.7 (9.7)

3.94

 13 years or over

25

53.0 (8.0)

−0.29

39.2 (10.7)

−0.55

Child’s gender

158

 Female

136

53.9 (8.3)

Reference

41.8 (11.6)

Reference

 Male

22

52.3 (10.4)

−1.60

41.9 (12.1)

0.10

Child’s country of birth

158

 North America

90

56.9 (5.9)

Reference

41.5 (12.1)

Reference

 The United Kingdom

12

54.2 (10.9)

−2.63

41.1 (8.4)

−0.40

 Australia and New Zealand

14

45.9 (7.4)

−10.98**

43.6 (12.5)

2.07

 Western Europe

29

47.6 (10.0)

−9.21**

41.2 (12.2)

−0.30

 Others

13

52.9 (8.2)

−3.93*

44.5 (9.7)

3.02

Mutation group

158

 No functional protein

50

53.5 (8.0)

Reference

43.0 (12.0)

Reference

 Missense/In-frame mutations

41

52.5 (9.9)

−0.97

39.5 (10.8)

−3.49

 Truncations aa172 to aa781

44

53.7 (8.7)

0.23

42.0 (11.5)

−0.98

 Truncations after aa781

12

53.6 (7.4)

0.15

46.2 (9.1)

3.21

 Mutations not grouped

11

58.5 (6.5)

5.05*

39.5 (15.1)

−3.49

Feeding pattern

153

 Oral intake only

114

54.3 (8.1)

Reference

41.0 (12.2)

Reference

 Combination use

14

55.0 (6.8)

0.74

39.7 (9.4)

−1.32

 Enteral nutrition only

25

49.6 (11.0)

−4.72**

47.4 (9.3)

6.37**

Dietary concerns

123

 None

62

55.9 (7.3)

Reference

41.9 (11.7)

Reference

 Occasional

39

51.8 (7.4)

−4.14**

39.9 (12.6)

−2.00

 Frequent or constant

22

55.7 (8.0)

−0.25

42.5 (10.3)

0.67

Floor sitting

129

 No assistance

83

54.3 (7.6)

Reference

41.7 (11.7)

Reference

 Some assistance

13

54.5 (7.8)

0.20

42.0 (12.5)

0.27

 Maximal assistance/unable

33

51.3 (10.3)

−3.02*

43.9 (10.6)

2.25

Taking 10 steps forward

126

 No assistance

28

54.8 (7.2)

Reference

41.6 (12.6)

Reference

 Some assistance

19

57.3 (7.2)

2.52

40.6 (14.3)

−0.95

 Maximal assistance/unable

79

52.4 (8.9)

−2.37

43.2 (10.4)

1.63

Eye contact

148

 No

78

53.0 (9.6)

Reference

41.0 (12.0)

Reference

 Yes

70

54.6 (7.3)

1.57

42.5 (11.7)

1.54

Communication

129

 No/Simple method

44

53.0 (9.0)

Reference

44.1 (9.6)

Reference

 Complex gestures/vocalisation

58

53.5 (8.5)

0.52

41.2 (12.4)

−2.91

 Sign/Spoken language

27

55.0 (7.5)

1.98

42.1 (12.0)

−2.02

Seizure frequency

146

 Absent

12

53.7 (7.5)

Reference

43.2 (11.3)

Reference

 Yearly/Monthly

15

53.4 (9.8)

−0.33

41.3 (13.1)

−1.82

 Weekly

26

54.5 (6.7)

0.84

40.5 (10.7)

−2.71

 1 to 5 times a day

69

53.4 (8.9)

−0.28

41.1 (12.7)

−2.09

 At least 5 times a day

24

54.2 (9.8)

0.49

45.6 (8.5)

2.47

Sleep difficulties

144

 1.00 to 1.50 (1^st quartile)

36

54.5 (8.3)

Reference

45.2 (11.3)

Reference

 1.50 to 1.81 (2^nd quartile)

38

54.1 (7.7)

−0.46

42.7 (10.8)

−2.58

 1.81 to 2.17 (3^rd quartile)

35

54.6 (7.5)

0.11

42.6 (11.2)

−2.63

 2.17 to 5.00 (4^th quartile)

35

52.5 (10.1)

−2.00

38.2 (12.1)

−7.06**

Hospitalisation rate

146

 0 to 0.38 (1^st quartile)

34

52.9 (7.8)

Reference

42.5 (10.2)

Reference

 0.38 to 0.86 (2^nd quartile)

38

54.6 (8.3)

1.66

43.0 (12.2)

0.50

 0.86 to 2.14 (3^rd quartile)

36

53.1 (8.4)

0.23

39.9 (10.3)

−2.60

 2.14 to 13.70 (4^th quartile)

38

54.0 (9.7)

1.11

43.7 (12.2)

1.19

Respite care

148

 None

36

54.4 (8.3)

Reference

42.7 (11.8)

Reference

 Formal only

21

52.0 (10.1)

−2.41

44.9 (8.3)

2.21

 Informal only

41

54.1 (8.6)

−0.26

41.1 (13.9)

−1.56

 Both formal and informal

50

53.2 (8.4)

−1.25

40.8 (10.4)

−1.85

Financial difficulty

144

 No

83

53.9 (8.5)

Reference

44.0 (11.2)

Reference

 Yes

61

52.9 (8.9)

−0.97

39.1 (11.6)

−4.89**