Table 3 Rate of persistent neck pain and adjusted odds ratio (ORadj) with 95% confidence intervals (95%CI) with respect to factors in the final modeling (n = 524)

Year of study

- 1^st year

183

21 (11.5)

1.00

- 2^nd year

247

47 (19.0)

1.90

1.08-3.35

0.027*

- 3^rd year

91

10 (11.0)

0.96

0.42-2.15

0.912

- 5^th year

3

1 (33.3)

7.09

0.57-87.70

0.127

Percent time of computer use for entertainment

- < 70

426

70 (16.4)

1.00

- ≥ 70

98

7 (9.2)

0.44

0.21-0.95

0.036*

Elbows positioned at 90° angle

- Yes

129

13 (10.1)

1.00

- No

395

66 (16.7)

1.76

0.92-3.35

0.087

Keyboard height

- Suitable

370

52 (14.1)

1.00

- Too high

85

22 (25.9)

2.18

1.21-3.91

0.009*

- Too low

69

5 (7.2)

0.46

0.17-1.20

0.113