Table 5 Univariate logistic regression of factors associated with NIHL among noise-exposed workers (n = 396) at two steel factories in Egypt, 2021

Highest qualification attained

 Never been to school^{^}

3

1.6

2

1.0

-

-

 Basic education

18

9.7

18

8.6

0.66 (0.09, 4.47)

0.677

 High school

131

70.4

147

70.0

0.59 (0.09, 3.61)

0.572

 Higher education

34

18.3

43

20.5

0.52 (0.08, 3.33)

0.496

Smoking

 Never been smoker^{^}

62

33.3

66

31.4

-

-

 Current/ex-smoker

124

66.7

144

68.6

0.91 (0.60, 1.39)

0.686

Ear-related medical condition

 No^{^}

168

90.3

194

92.4

-

-

 Yes

18

9.7

16

7.6

1.29 (0.64, 2.62)

0.467

Tinnitus

 No^{^}

161

86.6

195

92.9

-

-

 Yes

25

13.4

15

7.1

2.01 (1.03, 3.95)

0.041^*

Job nature

 Blue collar^{^}

185

99.5

205

97.6

-

-

 White collar

1

0.5

5

2.4

0.22 (0.02, 1.91)

0.171

Work schedule

 Daytime work^{^}

29

15.6

47

22.4

-

 Shiftwork

157

84.4

163

77.6

1.56 (0.93, 2.60)

0.088

Using hearing PPE at work

 No^{^}

93

50.0

126

60.0

-

-

 Yes, regular

15

8.1

11

5.2

1.84 (0.81, 4.20)

0.144

 Yes, irregular

78

41.9

73

34.8

1.44 (0.95, 2.19)

0.082

Job duration (years)

 < 10^{^}

121

65.1

156

74.3

-

-

 10– < 20

33

17.7

43

20.5

0.98 (0.59, 1.65)

0.968

 ≥ 20

32

17.2

11

5.2

3.78 (1.81, 7.74)

 < 0.001^***

Mean ± SD (Min–Max)

11.9 ± 8.4 (5–35)

9 ± 4.1 (5–27)

0.027^*a

Age (years)

 < 30^{^}

10

5.4

14

6.7

-

 30– < 40

92

49.5

136

64.8

0.94 (0.40, 2.22)

0.901

 40– < 50

54

29.0

54

25.7

1.40 (0.57, 3.42)

0.461

 ≥ 50

30

16.1

6

2.9

7.0 (2.12, 23.11)

0.001^**

Mean ± SD (Min–Max)

39.9 ± 8.5 (26–62)

37.1 ± 5.5 (25–55)

 < 0.001^***b