Table 1 Estimation for risk of development of ADHD in children in relation to socio-demographic characteristics, parental occupation, and parental smoking at home (Pediatric Alexandria University Hospital, 2022)

Age of mother at conception of the child under study (years)

 < 20

 20–35 (Ref)

 35+

8(6.4)

111(88)

7(5.6)

0 (0)

117 (92.8)

9 (7.2)

17.91 (1.02–31.4)

1

0.81 (0.2–2.2)

 Mean ± SD.

28.15 ± 4.6

29.33 ± 3.46

Age of father at conception of the child under study (years)

 20–39 (Ref)

 40+

105 (83.3)

21 (16.7)

114 (90.3)

12 (9.7)

1

1.9 (0.89–4.05)

 Mean ± SD.

34 ± 5.01

33.84 ± 4.64

Level of education of the mother

 Low

 Intermediate

 High (Ref)

66 (52.4)

27 (21.4)

33 (26.2)

15 (11.9)

15 (11.9)

96 (76.2)

12.80 (6.45–25.42)

5.24 (2.49–11.03)

1

Level of education of the father

 Low

 Intermediate

 High (Ref)

61 (48.4)

32 (25.4)

33 (26.2)

14 (11.1)

15 (11.9)

97 (77)

12.81 (6.35–25.85)

6.27 (3.02–13.01)

1

Crowding index

 < 1(Ref)

 1-

 2+

16 (12.7)

89 (69.1)

21 (18.2)

30 (23.8)

91 (72.3)

5 (3.9)

1

1.83 (0.94–3.6)

7.88 (2.5-24.84)

Parental consanguinity

 No (Ref)

 Yes

105 (83.3)

21 (16.7)

123 (97.6)

3 (2.4)

1

8.20 (2.38–28.26)

Mother occupation

 Housewives (Ref)

 Working

104 (82.5)

22 (17.5)

96 (76.2)

30 (23.8)

1

0.677 (0.367– 1.25)

Father occupation

 No work (Ref)

 Working

3 (2.4)

123 (97.6)

2 (1.6)

124 (98.4)

1

1.544 (0.90–2.64)

Exposure of the father to physical risk factors

 No (Ref)

 Yes

120 (95.2)

6 (4.8)

125 (99.2)

1 (0.8)

1

6.25 (0.74–52.69)

Exposure of the father to biological risk factors

 No (Ref)

 Yes

118 (93.7)

8 (6.3)

123 (97.6)

3 (2.4)

1

2.78 (0.72–10.73)

Exposure of the father to chemical risk factors

 No (Ref)

 Yes

77 (61.1)

49 (38.9)

123 (97.6)

3 (2.4)

1

26.09 (7.86–86.63)

Tobacco smoking of the mother

 No (Ref)

 Yes

90 (71.4)

36 (28.6)

107 (84.9)

19 (15.1)

1

2.25 (1.21–4.20)

Tobacco smoking of the father

 No (Ref)

62 (49.2)

66 (52.4)

1

 Yes

64 (50.8)

60 (47.6)

1.14 (0.69–1.86)