Table 1 Distribution of characteristics of parents included in the study

16

13.5

13

18.8

29

15.4

45

11.4

27

22.7

28

40.6

55

29.3

123

31.2

48

40.3

13

18.8

61

32.4

119

30.2

28

23.5

15

21.8

43

22.9

107

27.2

χ² = 4.07, 1 df, p = 0.046

χ² = 1.38, 1 df, p = 0.24

83

69.2

47

67.1

130

68.4

209

52.8

22

18.3

17

24.3

39

20.5

139

35.1

11

9.2

4

5.7

15

7.9

35

8.8

4

3.3

2

2.9

6

3.2

13

3.3

Fisher's exact, p = 0.689

χ² = 6.22, 1 df, p = 0.015

112

96.6

62

93.9

174

95.6

359

91.1

4

3.4

4

6.1

8

4.4

35

8.9

Fisher's exact, p = 0.464

χ² = 3.63, 1 df, p = 0.057

12

10.8

3

4.8

15

8.6

9

2.3

47

42.4

22

35.5

69

39.9

121

31.6

36

32.4

29

46.8

65

37.6

189

49.4

16

14.4

8

12.9

24

13.9

64

16.7

χ² = 1.71, 1 df, p = 0.193

χ² = 11.31, 1 df, p = 0.001

83

75.5

48

76.2

131

75.7

240

64

27

24.5

15

23.8

42

24.3

135

36

χ² = 0.012, 1 df, p = 0.913

χ² = 7.44, 1 df, p = 0.006

10

10.8

5

8.9

15

10.1

29

8.2

19

20.7

19

34

38

25.7

95

27

29

31.5

16

28.6

45

30.4

109

31

19

20.7

9

16

28

18.9

72

20.5

15

16.3

7

12.5

22

14.9

47

13.3

Fisher's exact, p = 0.526

χ² = 0.03, 1 df, p = 0.854

16

14

6

8.8

22

12

53

13.6

49

43

27

39.7

76

41.8

138

35.3

15

13.2

5

7.4

20

11

26

6.6

34

29.8

30

44.1

64

35.2

174

44.5

Fisher's exact, p = 0.2

χ² = 1.63, 1 df, p = 0.203

78

72.9

45

69.2

123

71.5

295

74.5

29

27.1

20

30.8

49

28.5

101

25.5

χ² = 0.27, 1 df, p = 0.605

χ² = 0.55, 1 df, p = 0.459

92

86

52

80

144

83.7

365

92.2

15

14

13

20

28

16.3

31

7.8

χ² = 1.06, 1 df, p = 0.303

χ² = 9.2, 1 df, p = 0.002

41

38.3

21

32.3

62

36

169

42.7

66

61.7

44

67.7

110

64

227

57.3

χ² = 0.63, 1 df, p = 0.426

χ² = 2.18, 1 df, p = 0.139