human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND This study exp and ed previous NIOSH-IRS research examining the effects of rest breaks and stretching exercises on symptoms and performance in data -entry workers . METHODS All workers spent 4 weeks with conventional breaks ( two 15 min breaks per day ) and 4 weeks with supplementary breaks ( two 15 min breaks plus four 5 min breaks per day ) . One-half were assigned at r and om to a group instructed to perform brief stretching exercises during breaks . The remainder comprised the " no stretching " ( control ) group . RESULTS 51 workers ( stretch group n = 21 ; no stretch group n = 30 ) completed the study symptom question naires . Discomfort and eyestrain were significantly lower with supplementary breaks , and supplementary breaks attenuated accumulation of discomfort and eyestrain during work sessions . Data -entry speed was significantly faster with supplementary breaks so that work output was maintained , despite replacing 20 min of work time with break time . In the stretch group , workers reported  stretching  during only 25 % of conventional breaks and 39 % of supplementary breaks , and no significant effects of stretching on discomfort or performance were observed . CONCLUSIONS These results provide further converging evidence that supplementary breaks reliably minimize discomfort and eyestrain without impairing productivity . Low compliance in performing stretches prevented valid assessment of stretching effects . Further research on stretching exercises and exercise compliance is warranted In practice the secondary prevention of work-related upper extremity ( WRUE ) symptoms generally targets biomechanical risk factors . Psychosocial risk factors have also been shown to play an important role in the development of WRUE symptom severity and future disability . The addition of a stress management component to biomechanically focused interventions may result in greater improvements in WRUE symptoms and functional limitations than intervening in the biomechanical risk factors alone . Seventy office workers with WRUE symptoms were r and omly assigned to an ergonomics intervention group ( assessment and modification of work station and stretching exercises ) or a combined ergonomic and job stress intervention group ( ergonomic intervention plus two 1-h workshops on the identification and management of workplace stress ) . Baseline , 3- and 12-month follow-up measures of observed ergonomic risks and self-reported ergonomic risks , job stress , pain , symptoms , functional limitation , and general physical and mental health were obtained from all participants . While both groups experienced significant decreases in pain , symptoms , and functional limitation from baseline to three months with improvements continuing to 12 months post baseline , no significant differences between groups were observed for any outcome measures . Findings indicate that the additional two-session job stress management component did not significantly enhance the short- or long-term improvements brought about by the ergonomic intervention alone BACKGROUND High rates of work-related injuries are seen among health care workers involved in lifting and transferring patients . We studied the effects of a participatory worker-management ergonomics team among hospital orderlies . METHODS This prospect i ve intervention trial examined work injuries and other outcomes before and after the intervention , with other hospital employees used as a concurrent control . All orderlies in a 1,200-bed urban hospital were studied using passively collected data ( mean employment during study period 100 - 110 orderlies ) ; 67 orderlies ( preintervention ) and 88 orderlies ( postintervention ) also completed a question naire . The intervention was the formation of a participatory ergonomics team with three orderlies , one supervisor , and technical advisors . This team design ed and implemented changes in training and work practice s. RESULTS The 2-year postintervention period was marked by decreased risks of work injury ( RR = 0.50 , 95 % CI 0.35 - 0.72 ) , lost time injury ( RR = 0.26 , 95 % CI 0.14 - 0.48 ) , and injury with three or more days of time loss ( RR = 0.19 , 95 % CI 0.07 - 0.53 ) . Total lost days declined from 136.2 to 23.0 annually per 100 full-time worker equivalents ( FTE ) . Annual workers ' compensation costs declined from $ 237/FTE to $ 139/FTE . The proportion of workers with musculoskeletal symptoms declined and there were statistically significant improvements in job satisfaction , perceived psychosocial stressors , and social support among the orderlies . CONCLUSION Substantial improvements in health and safety were seen following implementation of a participatory ergonomics program This study examined the effects of supplementary rest breaks on musculoskeletal discomfort , eyestrain , mood , and performance in data -entry workers . Two rest break schedules were compared in a within-subjects design . Workers alternated between a ‘ conventional ’ and a ‘ supplementary ’ schedule in 4-week intervals . The conventional schedule contained a 15-min break during the first half of the work shift and a 15-min break during the second half of the shift . The supplementary schedule contained the same two 15-min breaks , and a 5-min break during each hour which otherwise did not contain a break , for a total of 20 extra minutes of break time . Results are based on data from 42 workers . They indicated that discomfort in several areas of the body , and eyestrain , were significantly lower under the supplementary than under the conventional schedule . While symptoms increased from pre- to post-work periods under both schedules , the magnitude of the increases was significantly less under the supplementary schedule . In addition , increases in discomfort of the right forearm , wrist and h and over the course of the work week under the conventional schedule were eliminated under the supplementary schedule . These beneficial effects were obtained without reductions in data -entry performance Health and safety literature stresses the value of programs aim ed at preventing musculoskeletal injuries . The concepts of empowerment learning are often recommended as guidelines for worker education yet these approaches are largely untested . The present study compares the traditional approach involving lecture and discussion with a participatory method .  A sample of 102 participants employed at a central ized reservation facility was used . Participants were r and omly assigned to either the  traditional education group or  the participatory education group . Data collection utilized surveys completed by study participants and observational checklists completed by a trained observer . Data were collected prior to intervention and at approximately 3 , 6 , and 12 months post intervention . Results of data analysis provide no evidence that participatory methods are more effective than traditional methods in encouraging workers to position their work equipment correctly or to maintain good working postures to prevent musculoskeletal injuries Three groups of data entry female visual display terminal ( VDT ) workers from Norway ( n = 30 ) , Pol and ( n = 33 ) and the USA ( n = 29 ) were compared . Before intervention , the Norwegian group reported more neck pain compared with the Polish group . The Polish group reported less shoulder pain than both the U.S. and the Norwegian groups . The clinical examination documented fewer symptoms and signs of musculoskeletal illness among the Polish participants compared with the Norwegian and the U.S. groups . After intervention , the Norwegian group reported a reduction in neck pain while the U.S. group reported a reduction in shoulder pain . The Polish group reported an increase in neck , shoulder and forearm pain at follow-up compared to after intervention . The Polish group recorded higher flexion of the upper arm at follow-up parallel with an increase of pain in the upper part of the body . Visual discomfort showed variable results in the 3 countries This r and omized clinical trial evaluated the effects of keyboard keyswitch design on computer users with h and paresthesias . Twenty computer users were matched and r and omly assigned to keyboard A ( n = 10 ) or B ( n = 10 ) . The keyboards were of conventional layout and differed in keyswitch design . Various outcome measures were assessed during the 12 weeks of use . Subjects assigned keyboard A experienced a decrease in h and pain between weeks 6 and 12 when compared with keyboard B subjects ( P = 0.05 ) and demonstrated an improvement in the Phalen test time ( right h and , P = 0.006 ; left h and , P = 0.06 ) . Keyboard assignment had no significant effect on change in h and function or median nerve latency . We conclude that use of keyboard A for 12 weeks led to a reduction in h and pain and an improved physical examination finding when compared with keyboard B. There was no corresponding improvement in h and function or median nerve latency A group of routine data entry operators ( female ) was included in the Polish MEPS ( musculoskeletal — eyestrain— psychosocial — stress ) study . Before the intervention , ergonomic assessment revealed improper working conditions such as inadequate lighting , uncomfortable chairs , and lack of forearm and wrist support while medical examination revealed that trapezius muscle load along with upper arm , head and back angles were higher than advisable . Subjects complained about neck and shoulder pain , visual problems , and psychosocial conditions . The ergonomic intervention included installation of new luminaires and Venetian blinds , new chairs , repair of ventilators , and optometric corrections . The results after the intervention showed mainly improvement in chair comfort , lighting conditions , visual strain , and sitting posture . However , financial limitations did not allow satisfactory completion of the intervention leading to a mixed interpretation of the results Background : Call centre work with computers is associated with increased rates of upper body pain and musculoskeletal disorders . Methods : This one year , r and omised controlled intervention trial evaluated the effects of a wide forearm support surface and a trackball on upper body pain severity and incident musculoskeletal disorders among 182 call centre operators at a large healthcare company . Participants were r and omised to receive ( 1  ) ergonomics training only , ( 2 ) training plus a trackball , ( 3 ) training plus a forearm support , or ( 4 ) training plus a trackball and forearm support . Outcome measures were weekly pain severity scores and diagnosis of incident musculoskeletal disorder in the upper extremities or the neck/shoulder region based on physical examination performed by a physician blinded to intervention . Analyses using Cox proportional hazard models and linear regression models adjusted for demographic factors , baseline pain levels , and psychosocial job factors . Results : Post-intervention , 63 participants were diagnosed with one or more incident musculoskeletal disorders  . Hazard rate ratios showed a protective effect of the armboard for neck/shoulder disorders ( HR = 0.49 , 95 % CI 0.24 to 0.97 ) after adjusting for baseline pain levels and demographic and psychosocial factors . The armboard also significantly reduced neck/shoulder pain ( p = 0.01 ) and right upper extremity pain ( p = 0.002 ) in comparison to the control group . A return-on-investment model predicted a full return of armboard and installation costs within 10.6 months . Conclusion : Providing a large forearm support combined with ergonomic training is an effective intervention to prevent upper body musculoskeletal disorders and reduce upper body pain associated with computer work among call centre employees The effects of two different prevention programmes on : ( 1 ) reported neck , shoulder and back pain , ( 2 ) perceived physical exertion at work and perceived work-related psychosocial factors , were evaluated by question naires after 12 and 18 months . Female nursing aides and assistant nurses ( n = 282 ) working in the home-care services , were r and omly assigned to one of three groups for : ( 1 ) individually design ed physical training programme , ( 2 ) work-place stress management , ( 3 ) control group . Results revealed no significant differences between the three groups . However , improvements in low back pain were registered within both intervention groups for up to 18 months . Perceived physical exertion at work was reduced in the physical training group . Improvements in neck and shoulder pain did not differ within the three groups . Dissatisfaction with work-related , psychosocial factors was generally increased in all groups . As the aetiology of neck , shoulder and back disorders is multifactorial , a combination of the two intervention programmes might be preferable and should be further studied Sixteen full-time clerical and office workers participated in this prospect i ve parallel-r and omized trial . Intervention consisted of four hours of individualized training through a multi-faceted injury prevention program . In Phase I , musculoskeletal symptoms , stress , and energy levels were measured before and after intervention . Differences between Group A ( intervention ) and Group B ( control ) were described ; pre to post differences between members within each group were also described . In Phase II , there were a greater number of statistically and clinical ly relevant differences within Group A at week 16 ( eleven weeks following intervention ) than at week five ( immediately post-intervention ) . The eyes , neck , shoulder , elbow-forearm , and wrist-h and were impacted most positively by intervention , however , the frequency and intensity of headaches increased . Stress and energy level differences were minimal . Group B workers received intervention during weeks 18 - 21 . Differences in average measures from pre to immediately post-intervention were greater within Group B than Group A. Both groups reported fewer sick days during the month of intervention than during pre and post-intervention months Background and Purpose The purpose of this study was to evaluate the efficacy of a preventive ergonomic intervention , which was provided by physical therapists , on spinal and upper-extremity work-related posture and symptom complaints of workers who use video display terminals ( VDT ) . Subjects Two hundred employees who spent at least 20 hours per week at a VDT were r and omly divided into 2 groups . Group E received the ergonomic intervention and an informative brochure , and group I received only the brochure . Methods Both groups were evaluated at the beginning of the study and at a follow-up 5 months later . The following tools were used : a pain drawing and the Rapid Entire Body Assessment ( REBA ) method to assess spinal and upper-extremity work-related posture . Results Group E had a lower REBA score and reduced lower back , neck , and shoulder symptoms compared with group I. Discussion and Conclusion The results suggest that a personalized preventive ergonomic intervention can improve spinal and upper-extremity work-related posture and musculoskeletal symptoms for workers who use VDTs The Norwegian MEPS ( musculoskelet 
    Output:
    
agent
Levels of evidence for interventions associated with positive effects were : Moderate evidence for arm supports ; and Limited evidence for ergonomics training plus workstation adjustments , new chair and rest breaks .
Levels of evidence for interventions associated with “ no effect ” were : Strong evidence for workstation adjustment alone ; Moderate evidence for biofeedback training and job stress management training ; and Limited evidence for cognitive behavioral training .
No interventions were associated with “ negative effects ” .
Conclusion It is difficult to make strong evidence d-based recommendations about what practitioners should do to prevent or manage upper extremity MSDs .
There is a paucity of high quality OHS interventions evaluating upper extremity MSDs and none focused on traumatic injury outcomes or workplace m and ated pre-placement screening exams .
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND This study exp and ed previous NIOSH-IRS research examining the effects of rest breaks and stretching exercises on symptoms and performance in data -entry workers . METHODS All workers spent 4 weeks with conventional breaks ( two 15 min breaks per day ) and 4 weeks with supplementary breaks ( two 15 min breaks plus four 5 min breaks per day ) . One-half were assigned at r and om to a group instructed to perform brief stretching exercises during breaks . The remainder comprised the " no stretching " ( control ) group . RESULTS 51 workers ( stretch group n = 21 ; no stretch group n = 30 ) completed the study symptom question naires . Discomfort and eyestrain were significantly lower with supplementary breaks , and supplementary breaks attenuated accumulation of discomfort and eyestrain during work sessions . Data -entry speed was significantly faster with supplementary breaks so that work output was maintained , despite replacing 20 min of work time with break time . In the stretch group , workers reported  stretching  during only 25 % of conventional breaks and 39 % of supplementary breaks , and no significant effects of stretching on discomfort or performance were observed . CONCLUSIONS These results provide further converging evidence that supplementary breaks reliably minimize discomfort and eyestrain without impairing productivity . Low compliance in performing stretches prevented valid assessment of stretching effects . Further research on stretching exercises and exercise compliance is warranted In practice the secondary prevention of work-related upper extremity ( WRUE ) symptoms generally targets biomechanical risk factors . Psychosocial risk factors have also been shown to play an important role in the development of WRUE symptom severity and future disability . The addition of a stress management component to biomechanically focused interventions may result in greater improvements in WRUE symptoms and functional limitations than intervening in the biomechanical risk factors alone . Seventy office workers with WRUE symptoms were r and omly assigned to an ergonomics intervention group ( assessment and modification of work station and stretching exercises ) or a combined ergonomic and job stress intervention group ( ergonomic intervention plus two 1-h workshops on the identification and management of workplace stress ) . Baseline , 3- and 12-month follow-up measures of observed ergonomic risks and self-reported ergonomic risks , job stress , pain , symptoms , functional limitation , and general physical and mental health were obtained from all participants . While both groups experienced significant decreases in pain , symptoms , and functional limitation from baseline to three months with improvements continuing to 12 months post baseline , no significant differences between groups were observed for any outcome measures . Findings indicate that the additional two-session job stress management component did not significantly enhance the short- or long-term improvements brought about by the ergonomic intervention alone BACKGROUND High rates of work-related injuries are seen among health care workers involved in lifting and transferring patients . We studied the effects of a participatory worker-management ergonomics team among hospital orderlies . METHODS This prospect i ve intervention trial examined work injuries and other outcomes before and after the intervention , with other hospital employees used as a concurrent control . All orderlies in a 1,200-bed urban hospital were studied using passively collected data ( mean employment during study period 100 - 110 orderlies ) ; 67 orderlies ( preintervention ) and 88 orderlies ( postintervention ) also completed a question naire . The intervention was the formation of a participatory ergonomics team with three orderlies , one supervisor , and technical advisors . This team design ed and implemented changes in training and work practice s. RESULTS The 2-year postintervention period was marked by decreased risks of work injury ( RR = 0.50 , 95 % CI 0.35 - 0.72 ) , lost time injury ( RR = 0.26 , 95 % CI 0.14 - 0.48 ) , and injury with three or more days of time loss ( RR = 0.19 , 95 % CI 0.07 - 0.53 ) . Total lost days declined from 136.2 to 23.0 annually per 100 full-time worker equivalents ( FTE ) . Annual workers ' compensation costs declined from $ 237/FTE to $ 139/FTE . The proportion of workers with musculoskeletal symptoms declined and there were statistically significant improvements in job satisfaction , perceived psychosocial stressors , and social support among the orderlies . CONCLUSION Substantial improvements in health and safety were seen following implementation of a participatory ergonomics program This study examined the effects of supplementary rest breaks on musculoskeletal discomfort , eyestrain , mood , and performance in data -entry workers . Two rest break schedules were compared in a within-subjects design . Workers alternated between a ‘ conventional ’ and a ‘ supplementary ’ schedule in 4-week intervals . The conventional schedule contained a 15-min break during the first half of the work shift and a 15-min break during the second half of the shift . The supplementary schedule contained the same two 15-min breaks , and a 5-min break during each hour which otherwise did not contain a break , for a total of 20 extra minutes of break time . Results are based on data from 42 workers . They indicated that discomfort in several areas of the body , and eyestrain , were significantly lower under the supplementary than under the conventional schedule . While symptoms increased from pre- to post-work periods under both schedules , the magnitude of the increases was significantly less under the supplementary schedule . In addition , increases in discomfort of the right forearm , wrist and h and over the course of the work week under the conventional schedule were eliminated under the supplementary schedule . These beneficial effects were obtained without reductions in data -entry performance Health and safety literature stresses the value of programs aim ed at preventing musculoskeletal injuries . The concepts of empowerment learning are often recommended as guidelines for worker education yet these approaches are largely untested . The present study compares the traditional approach involving lecture and discussion with a participatory method .  A sample of 102 participants employed at a central ized reservation facility was used . Participants were r and omly assigned to either the  traditional education group or  the participatory education group . Data collection utilized surveys completed by study participants and observational checklists completed by a trained observer . Data were collected prior to intervention and at approximately 3 , 6 , and 12 months post intervention . Results of data analysis provide no evidence that participatory methods are more effective than traditional methods in encouraging workers to position their work equipment correctly or to maintain good working postures to prevent musculoskeletal injuries Three groups of data entry female visual display terminal ( VDT ) workers from Norway ( n = 30 ) , Pol and ( n = 33 ) and the USA ( n = 29 ) were compared . Before intervention , the Norwegian group reported more neck pain compared with the Polish group . The Polish group reported less shoulder pain than both the U.S. and the Norwegian groups . The clinical examination documented fewer symptoms and signs of musculoskeletal illness among the Polish participants compared with the Norwegian and the U.S. groups . After intervention , the Norwegian group reported a reduction in neck pain while the U.S. group reported a reduction in shoulder pain . The Polish group reported an increase in neck , shoulder and forearm pain at follow-up compared to after intervention . The Polish group recorded higher flexion of the upper arm at follow-up parallel with an increase of pain in the upper part of the body . Visual discomfort showed variable results in the 3 countries This r and omized clinical trial evaluated the effects of keyboard keyswitch design on computer users with h and paresthesias . Twenty computer users were matched and r and omly assigned to keyboard A ( n = 10 ) or B ( n = 10 ) . The keyboards were of conventional layout and differed in keyswitch design . Various outcome measures were assessed during the 12 weeks of use . Subjects assigned keyboard A experienced a decrease in h and pain between weeks 6 and 12 when compared with keyboard B subjects ( P = 0.05 ) and demonstrated an improvement in the Phalen test time ( right h and , P = 0.006 ; left h and , P = 0.06 ) . Keyboard assignment had no significant effect on change in h and function or median nerve latency . We conclude that use of keyboard A for 12 weeks led to a reduction in h and pain and an improved physical examination finding when compared with keyboard B. There was no corresponding improvement in h and function or median nerve latency A group of routine data entry operators ( female ) was included in the Polish MEPS ( musculoskeletal — eyestrain— psychosocial — stress ) study . Before the intervention , ergonomic assessment revealed improper working conditions such as inadequate lighting , uncomfortable chairs , and lack of forearm and wrist support while medical examination revealed that trapezius muscle load along with upper arm , head and back angles were higher than advisable . Subjects complained about neck and shoulder pain , visual problems , and psychosocial conditions . The ergonomic intervention included installation of new luminaires and Venetian blinds , new chairs , repair of ventilators , and optometric corrections . The results after the intervention showed mainly improvement in chair comfort , lighting conditions , visual strain , and sitting posture . However , financial limitations did not allow satisfactory completion of the intervention leading to a mixed interpretation of the results Background : Call centre work with computers is associated with increased rates of upper body pain and musculoskeletal disorders . Methods : This one year , r and omised controlled intervention trial evaluated the effects of a wide forearm support surface and a trackball on upper body pain severity and incident musculoskeletal disorders among 182 call centre operators at a large healthcare company . Participants were r and omised to receive ( 1  ) ergonomics training only , ( 2 ) training plus a trackball , ( 3 ) training plus a forearm support , or ( 4 ) training plus a trackball and forearm support . Outcome measures were weekly pain severity scores and diagnosis of incident musculoskeletal disorder in the upper extremities or the neck/shoulder region based on physical examination performed by a physician blinded to intervention . Analyses using Cox proportional hazard models and linear regression models adjusted for demographic factors , baseline pain levels , and psychosocial job factors . Results : Post-intervention , 63 participants were diagnosed with one or more incident musculoskeletal disorders  . Hazard rate ratios showed a protective effect of the armboard for neck/shoulder disorders ( HR = 0.49 , 95 % CI 0.24 to 0.97 ) after adjusting for baseline pain levels and demographic and psychosocial factors . The armboard also significantly reduced neck/shoulder pain ( p = 0.01 ) and right upper extremity pain ( p = 0.002 ) in comparison to the control group . A return-on-investment model predicted a full return of armboard and installation costs within 10.6 months . Conclusion : Providing a large forearm support combined with ergonomic training is an effective intervention to prevent upper body musculoskeletal disorders and reduce upper body pain associated with computer work among call centre employees The effects of two different prevention programmes on : ( 1 ) reported neck , shoulder and back pain , ( 2 ) perceived physical exertion at work and perceived work-related psychosocial factors , were evaluated by question naires after 12 and 18 months . Female nursing aides and assistant nurses ( n = 282 ) working in the home-care services , were r and omly assigned to one of three groups for : ( 1 ) individually design ed physical training programme , ( 2 ) work-place stress management , ( 3 ) control group . Results revealed no significant differences between the three groups . However , improvements in low back pain were registered within both intervention groups for up to 18 months . Perceived physical exertion at work was reduced in the physical training group . Improvements in neck and shoulder pain did not differ within the three groups . Dissatisfaction with work-related , psychosocial factors was generally increased in all groups . As the aetiology of neck , shoulder and back disorders is multifactorial , a combination of the two intervention programmes might be preferable and should be further studied Sixteen full-time clerical and office workers participated in this prospect i ve parallel-r and omized trial . Intervention consisted of four hours of individualized training through a multi-faceted injury prevention program . In Phase I , musculoskeletal symptoms , stress , and energy levels were measured before and after intervention . Differences between Group A ( intervention ) and Group B ( control ) were described ; pre to post differences between members within each group were also described . In Phase II , there were a greater number of statistically and clinical ly relevant differences within Group A at week 16 ( eleven weeks following intervention ) than at week five ( immediately post-intervention ) . The eyes , neck , shoulder , elbow-forearm , and wrist-h and were impacted most positively by intervention , however , the frequency and intensity of headaches increased . Stress and energy level differences were minimal . Group B workers received intervention during weeks 18 - 21 . Differences in average measures from pre to immediately post-intervention were greater within Group B than Group A. Both groups reported fewer sick days during the month of intervention than during pre and post-intervention months Background and Purpose The purpose of this study was to evaluate the efficacy of a preventive ergonomic intervention , which was provided by physical therapists , on spinal and upper-extremity work-related posture and symptom complaints of workers who use video display terminals ( VDT ) . Subjects Two hundred employees who spent at least 20 hours per week at a VDT were r and omly divided into 2 groups . Group E received the ergonomic intervention and an informative brochure , and group I received only the brochure . Methods Both groups were evaluated at the beginning of the study and at a follow-up 5 months later . The following tools were used : a pain drawing and the Rapid Entire Body Assessment ( REBA ) method to assess spinal and upper-extremity work-related posture . Results Group E had a lower REBA score and reduced lower back , neck , and shoulder symptoms compared with group I. Discussion and Conclusion The results suggest that a personalized preventive ergonomic intervention can improve spinal and upper-extremity work-related posture and musculoskeletal symptoms for workers who use VDTs The Norwegian MEPS ( musculoskelet 
    Output:
    