. 2020 Jun 9;21:366. doi: 10.1186/s12891-020-03379-y

Table 3.

Potential risk factors grouped into the international classification of function and disability (ICF)

Study	Body Functions and Structures	Activities and Participation	Environmental factors	Personal factors
Dieck et al. From Table 6^a	• Shoulder elevation^c • Hip elevation^c • Deviation of the spine^c • Scoliosis: X² = 0.001 (p = 0.98) • Kyphosis (normal): X² = 6.38 (p = 0.09) • Lordosis (normal): X² = 1.05 (p = 0.79) • Pelvic tilt (normal):X² = 0.19 (p = 0.91)
Grimby Ekman et al. [36] From Table 6^a	• Asthma: crude OR = 2.0 (p = 0.046)^b • Asthma: adj. OR = 2.0 (0.996–3.91) • Perceived stress: adj. OR 1.7 (1.13–2.63)^b • Overweight: OR = 0.80 (p = 0.522)	• Computer use pattern: - One 4 h period without a break: adj. OR = 1.7 (0.941–2.94) - At least two 4 h periods without a break adj. OR = 1.8 (1.16–2.89)^b • Physical activity: OR = 0.99 (p = 0.599) • Breakfast regularly: OR = 0.81 (p = 0.423) • Work/study time: OR 1.0 (p = 0.889) • High work/study demands - Not affecting home life: adj. OR = 1.4 (0.913–2.20) - Affecting home life: adj. OR = 1.1 (0.596–2.12) • High home life demands: adj. OR = 2.2 (0.912–5.07) • Good relationships with superiors: OR = 0.67 (p = 0.280) • Good relationships with colleagues: adj. OR = 0.72 (0.354–1.48)		• Being female: adj. OR 3.1 (2.00–4.82)^b • Snuff use: OR = not reported • Smoking: OR = 1.2 (p = 0.685)
Gustafsson et al. [35] From table 3^a		One year follow-up: - High stable, Short message service (SMS) (> 11 per day): adj. OR = 1.0 (0.69–1.58) - Stable SMS: OR = 1 Five year follow up: - High stable SMS: adj. OR = 1.3 (0.76–2.19) - Stable SMS: OR = 1
Kanchanomai et al. [34] From Table 2 and 3^a	• Neck extensor and flexor endurance^c • Neck range of motion (ROM), extension, flexion, rotation and lateral rotation ^c • Pectoralis major muscle length^c • Upper limb nerve tension test ^c • ROM elbow extension ^c • Chronic diseases^c • Mental health ^c • Body mass index^c	• Elbows positioned at 90° angle while using computer - Yes: adj. OR = 1.00 - No: adj. OR = 1.52 (0.99–2.31) • Percent duration of mouse use while working at desk - < 70: adj. OR = 1.00 - ≥ 70: adj. OR = 0.66 (0.42–1.04) • Physical activity^c • Average amount of daily computer use^c • Years of computer use^c • Year of study - 1st year: adj. OR = 1.00 - 2nd year: adj. OR = 1.90 (1.08–3.35)^b - 3rd year: adj. OR = 0.96 (0.42–2.15) - 5th year: adj. OR = 7.09 (0.57–87.70) • Percent time of computer use for entertainment - < 70: adj. OR = 1.00 - ≥ 70: adj. OR = 0.44 (0.21–0.95)^b	• Type of computer^c • Support of head, upper back, low back and arms while using computer • Computer screen positioned at eye level - Yes: adj. OR = 1.00 - No: adj. OR = 1.64 (1.13–2.36) ^b • Mouse height - Suitable: adj. OR = 1.00 - Too high: adj. 1.30 (0.82–2.10) - Too low: adj. OR = 0.52 (0.28–0.99)^b • Keyboard height - Suitable: adj. OR = 1.00 - Too low: adj. OR = 0.46 (0.17–1.20) - Too high: adj. OR = 2.18 (1.21–3.91)^b	• Gender^c • Age^c • Field of study^c
Siivola et al. [39] From table 3^a	• Physical condition - Good or fairly good: RR = 1 - Moderate: RR = 1.3 (0.8–2.2) - Fairly poor or poor: RR = 0.9 (0.4–2.5) • Depressive mood - As continuous variable: RR = 1.1 (0.9–1.2) Symptoms decreased: RR = 1 (0.6–1.6) - Symptoms unchanged: RR = 1 - Symptoms increased: RR = 1.3 (0.8–2.1) • Psychosomatic symptoms score (crude): - As continuous variable: RR = 1 (1.0–1.1)* - Symptoms decreased: RR = 0.6 (0.3–1.0) - Symptoms unchanged: RR = 1 - Symptoms increased: RR = 1.5 (0.9–2.6) • BMI - Quartile 1: RR = 1 - Quartile 2: RR = 1 (0.5–1.9) - Quartile 3: RR = 1 (0.4–2.1) - Quartile 4: RR = 1 (0.5–1.9) • Height - Quartile 1: RR = 1 - Quartile 2: RR = 1.5 (0.7–3.1) - Quartile 3: RR = 1.6 (0.8–3.3) • Quartile 4: RR = 0.9 (0.4–2.1) • Panting and sweating in physical exercise (intensity of physical activity) - A lot: RR = 1 - Somewhat: RR = 1.5 (0.7–3.4) - A little/not at all/no exercise: RR = 1.3 (0.7–2.5)	• School achievement (grade points) - Quartile 1:RR = 1 - Quartile 2:RR = 1.7 (0.7–4.1) - Quartile 3: RR = 1 (0.4–2.3) - Quartile 4: RR = 1 (0.4–2.5) • Time spent on homework • School mark for physical education: RR = 0.9 (0.7–1.2) • Physical activity leisure time - Very active: RR = 1 - Fairly active: RR = 1.1 (0.6–2.2) - Fairly passive: RR = 1.4 (0.6–2.9) - Very passive: RR = 1.3 (0.6–2.8) • Type of leisure activity - Sport activities involving dynamic loading of upper extremities: RR = 0.8 (0.4–1.5) - Other sports: RR = 1.2 (0.3–4.7) - Hobbies that statically load the upper extremities: RR = 1.2 (0.3–4.7) - Other hobbies: RR = 1 (0.4–2.4)		• Gender - Male: 1 - Female: RR = 1.3 (0.8–2.2) • Seeking health care for NSP - Quartile 1: RR = 1 - Quartile 2: RR = 1.4 (0.7–2.9) - Quartile 3: RR = 1 (0.5–2.0) - Quartile 4:RR = 1.1 (0.6–2.3)
Timpka et al. [38] From table 2^a	• Isometric muscle strength - Low: adj. RR = 0.93 (0.83–1.03) - High: adj. RR = 1.00 (0.90–1.10)

Study

Body Functions and Structures

Activities and Participation

Environmental factors

Personal factors

Dieck et al.

From Table 6^a

• Shoulder elevation^c

• Hip elevation^c

• Deviation of the spine^c

• Scoliosis: X² = 0.001 (p = 0.98)

• Kyphosis (normal): X² = 6.38 (p = 0.09)

• Lordosis (normal): X² = 1.05 (p = 0.79)

• Pelvic tilt (normal):X² = 0.19 (p = 0.91)

Grimby Ekman et al. [36]

From Table 6^a

• Asthma: crude OR = 2.0 (p = 0.046)^b

• Asthma: adj. OR = 2.0 (0.996–3.91)

• Perceived stress: adj. OR 1.7 (1.13–2.63)^b

• Overweight: OR = 0.80 (p = 0.522)

• Computer use pattern:

- One 4 h period without a break: adj. OR = 1.7 (0.941–2.94)

- At least two 4 h periods without a break adj. OR = 1.8 (1.16–2.89)^b

• Physical activity: OR = 0.99 (p = 0.599)

• Breakfast regularly: OR = 0.81 (p = 0.423)

• Work/study time: OR 1.0 (p = 0.889)

• High work/study demands

- Not affecting home life: adj. OR = 1.4 (0.913–2.20)

- Affecting home life: adj. OR = 1.1 (0.596–2.12)

• High home life demands: adj. OR = 2.2 (0.912–5.07)

• Good relationships with superiors: OR = 0.67 (p = 0.280)

• Good relationships with colleagues: adj. OR = 0.72 (0.354–1.48)

• Being female: adj. OR 3.1 (2.00–4.82)^b

• Snuff use: OR = not reported

• Smoking: OR = 1.2 (p = 0.685)

Gustafsson et al. [35]

From table 3^a

One year follow-up:

- High stable, Short message service (SMS) (> 11 per day): adj. OR = 1.0 (0.69–1.58)

- Stable SMS: OR = 1

Five year follow up:

- High stable SMS: adj. OR = 1.3 (0.76–2.19)

- Stable SMS: OR = 1

Kanchanomai et al. [34]

From Table 2 and 3^a

• Neck extensor and flexor endurance^c

• Neck range of motion (ROM), extension, flexion, rotation and lateral rotation ^c

• Pectoralis major muscle length^c

• Upper limb nerve tension test ^c

• ROM elbow extension ^c

• Chronic diseases^c

• Mental health ^c

• Body mass index^c

• Elbows positioned at 90° angle while using computer

- Yes: adj. OR = 1.00

- No: adj. OR = 1.52 (0.99–2.31)

• Percent duration of mouse use while working at desk

- < 70: adj. OR = 1.00

- ≥ 70: adj. OR = 0.66 (0.42–1.04)

• Physical activity^c

• Average amount of daily computer use^c

• Years of computer use^c

• Year of study

- 1st year: adj. OR = 1.00

- 2nd year: adj. OR = 1.90 (1.08–3.35)^b

- 3rd year: adj. OR = 0.96 (0.42–2.15)

- 5th year: adj. OR = 7.09 (0.57–87.70)

• Percent time of computer use for entertainment

- < 70: adj. OR = 1.00

- ≥ 70: adj. OR = 0.44 (0.21–0.95)^b

• Type of computer^c

• Support of head, upper back, low back and arms while using computer

• Computer screen positioned at eye level

- Yes: adj. OR = 1.00

- No: adj. OR = 1.64 (1.13–2.36) ^b

• Mouse height

- Suitable: adj. OR = 1.00

- Too high: adj. 1.30 (0.82–2.10)

- Too low: adj. OR = 0.52 (0.28–0.99)^b

• Keyboard height

- Suitable: adj. OR = 1.00

- Too low: adj. OR = 0.46 (0.17–1.20)

- Too high: adj. OR = 2.18 (1.21–3.91)^b

• Gender^c

• Age^c

• Field of study^c

Siivola et al. [39]

From table 3^a

• Physical condition

- Good or fairly good: RR = 1

- Moderate: RR = 1.3 (0.8–2.2)

- Fairly poor or poor: RR = 0.9 (0.4–2.5)

• Depressive mood

- As continuous variable: RR = 1.1 (0.9–1.2)

Symptoms decreased: RR = 1 (0.6–1.6)

- Symptoms unchanged: RR = 1

- Symptoms increased: RR = 1.3 (0.8–2.1)

• Psychosomatic symptoms score (crude):

- As continuous variable: RR = 1 (1.0–1.1)*

- Symptoms decreased: RR = 0.6 (0.3–1.0)

- Symptoms unchanged:

RR = 1

- Symptoms increased: RR = 1.5 (0.9–2.6)

• BMI

- Quartile 1: RR = 1

- Quartile 2: RR = 1 (0.5–1.9)

- Quartile 3: RR = 1 (0.4–2.1)

- Quartile 4: RR = 1 (0.5–1.9)

• Height

- Quartile 1: RR = 1

- Quartile 2: RR = 1.5 (0.7–3.1)

- Quartile 3: RR = 1.6 (0.8–3.3)

• Quartile 4: RR = 0.9 (0.4–2.1)

• Panting and sweating in physical exercise (intensity of physical activity)

- A lot: RR = 1

- Somewhat: RR = 1.5 (0.7–3.4)

- A little/not at all/no exercise: RR = 1.3 (0.7–2.5)

• School achievement (grade points)

- Quartile 1:RR = 1

- Quartile 2:RR = 1.7 (0.7–4.1)

- Quartile 3: RR = 1 (0.4–2.3)

- Quartile 4: RR = 1 (0.4–2.5)

• Time spent on homework

• School mark for physical education: RR = 0.9 (0.7–1.2)

• Physical activity leisure time

- Very active: RR = 1

- Fairly active: RR = 1.1 (0.6–2.2)

- Fairly passive: RR = 1.4 (0.6–2.9)

- Very passive: RR = 1.3 (0.6–2.8)

• Type of leisure activity

- Sport activities involving dynamic loading of upper extremities: RR = 0.8 (0.4–1.5)

- Other sports: RR = 1.2 (0.3–4.7)

- Hobbies that statically load the upper extremities: RR = 1.2 (0.3–4.7)

- Other hobbies: RR = 1 (0.4–2.4)

• Gender

- Male: 1

- Female: RR = 1.3 (0.8–2.2)

• Seeking health care for NSP

- Quartile 1: RR = 1

- Quartile 2: RR = 1.4 (0.7–2.9)

- Quartile 3: RR = 1 (0.5–2.0)

- Quartile 4:RR = 1.1 (0.6–2.3)

Timpka et al. [38]

From table 2^a

• Isometric muscle strength

- Low: adj. RR = 0.93 (0.83–1.03)

- High: adj. RR = 1.00 (0.90–1.10)

a Results from tables in original studies

b Significant results

c Non-significant results, risk estimates not presented in original article

OR odds ratio, adj. OR adjusted odds ratio, RR relative risk, adj. RR adjusted relative risk, p p-value, 95% CI 95% confidence interval, SMS short message service