Table 2

Prevalence and incidence of right side symptom forearm cases and clinical forearm case characteristics*

CategoriesAt baselineSymptom forearm cases at baseline n=296Clinical forearm cases at baseline† n=21At 1 year follow upSymptom forearm cases at follow up n=67
nn%n%nn%
*Missing values are not included. Participants using both hands operating the computer mouse (n=623) are included.
†Clinical forearm cases and participants with signs of supinator syndrome, pronator teres syndrome.
Physical workplace factors
Hours per week with mouse in right hand0–2.41552553.530.21279131.0
2.5–4474112.310.238020.5
5–9845323.820.267671.0
10–141200332.810.1980121.2
15–191086666.150.5877111.3
20–24861364.250.670691.3
25–30372328.600.031320.6
>30292248.241.424883.2
Arm/wrist support during use of mouseNo1652674.130.21350151.1
0–50% of time615264.200.048481.7
50–100% of time42961934.5170.43530391.1
Abnormal mouse positionNo64242834.4210.35250601.1
Yes519132.500.040871.7
Keyboard time in hours per week0–2.4663243.620.352991.7
2.5–41217635.240.398791.0
5–92291853.760.31871201.1
10–141607613.860.41342141.0
15–19759455.930.4604111.8
20–2419194.700.016621.2
25–306934.300.05400.0
>303725.400.03013.3
Arm/wrist support during use of keyboardNo25071024.140.22052281.4
0–50% of time1400745.360.41133111.0
50–100% of time28701164.0110.42359261.1
Abnormal keyboard positionNo58182464.2210.44768561.2
Yes911465.000.0735101.4
Work chair adjustedNo223146.300.018110.6
Yes66712824.210.015448661.2
Work desk adjustedNo1692593.530.21349110.8
Yes51782334.5180.34264561.3
Satisfied with workplace designNo920677.320.273581.1
Yes59812283.8190.34898591.2
Psychosocial workplace factors
High demandsNo40941613.9140.33407331.0
Yes27981344.870.32213321.5
Low controlNo46611723.7120.33776411.1
Yes22231245.690.41845241.3
Low social supportNo40861403.440.13339351.0
Yes27551495.4150.52238291.3
StrainNo60952464.0180.34977551.1
Yes781496.330.4628101.6
Time pressureNo51581903.7170.34231441.0
Yes17411066.140.21400221.6
Personal characteristics
Negative affectivityNo57722504.3190.34714521.1
Yes935394.220.2765131.7
Type A behaviourNo57252344.1190.34713521.1
Yes916525.720.270681.1
Age (years)20–29654335.010.247871.5
30–3925921023.9100.42025150.7
40–4922011034.760.31858201.1
50–591397584.240.31215251.9
60–669900.000.08200.0
GenderMale2596642.530.12042160.8
Female43472325.3180.43614511.4
BMILow21662.800.018021.1
Normal62312644.2170.35077591.2
High371205.410.330831.0
Poor social networkNo61892644.3170.35041581.2
Yes590284.740.749271.4
Leisure time physical activityLow39381834.6130.33218421.3
High29301133.980.32369231.0
Chronic diseasesNo65062734.2210.35282601.1
Yes437235.300.037671.9
Pain started after forearm accidentNo67552864.2200.35629661.2
Yes188105.300.02913.4