Table 2 Odds ratios (OR) and their 95% confidence interval (Cl) for frequent computer-associated health complaints by time (hours) spent daily on a computer, among 12- to 18-year-old computer users, adjusted for age, sex and parents' education.

Not daily

319 *

1.0

181

1.0

180

1.0

89

1.0

73

1.0

< 1 hour daily

57

0.8 (0.6-1.0)

44

1.1 (0.8-1.5)

43

1.0 (0.7-1.5)

19

1.0 (0.6-1.5)

13

0.8 (0.4-1.4)

1-3 hours daily

68

0.8 (0.6-1.0)

67

1.5 (1.1-2.0)

58

1.3 (0.9-1.7)

39

1.6 (1.1-2.3)

22

1.1 (0.7-1.7)

≥4 hours daily

16

2.0 (1.1-3.5)

10

2.2 (1.1-4.2)

12

2.8 (1.5-5.1)

13

5.4 (2.9-10.1)

6

2.6 (1.1-6.1)