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 .
Background Little is known about the most effective occupational health and safety ( OHS ) interventions to reduce  upper extremity musculoskeletal disorders ( MSDs ) and injuries .
Methods A systematic review used a best evidence synthesis approach to address the question : “ do occupational health and safety interventions have an effect on upper extremity musculoskeletal symptoms , signs , disorders , injuries , cl aims and lost time ? ”
A randomised controlled trial of postural interventions for prevention of musculoskeletal symptoms among computer users
Aims : To examine the effect of two workstation and postural interventions on the incidence of  musculoskeletal symptoms among computer users . Methods : R and omised controlled trial of two distinct workstation and postural interventions ( an alternate intervention and a conventional intervention ) among 376 persons using computer keyboards for more than 15 hours per week . The incidence of neck/shoulder symptoms and h and /arm symptoms during six months of follow up among individuals in the intervention groups was compared to the incidence in computer users who did not receive an intervention ( comparison group ) . For individuals in the intervention groups , study staff adjusted workstations , where possible , and trained individuals to assume the intervention postures . Individuals reported musculoskeletal symptoms in a weekly diary . Participants who reported discomfort intensity of 6 or greater on a 0–10 visual analogue scale or who reported musculoskeletal symptoms requiring use of analgesic medication were considered symptomatic . Results : There were no significant differences in the incidence of musculoskeletal symptoms among the three intervention groups . Twenty two ( 18.5 % ) participants in the alternate intervention group , 25 ( 20.2 % ) in the conventional intervention group , and 25 ( 21.7 % ) in the comparison group developed incident arm or h and symptoms . Thirty eight ( 33.3 % ) participants in the alternate intervention group , 36 ( 31.0 % ) in the conventional intervention group , and 33 ( 30.3 % ) in the comparison group developed incident neck or shoulder symptoms . Compliance with all components of the intervention was attained for only 25–38 % of individuals , due mainly to the inflexibility of workstation configurations . Conclusions : This study provides evidence that two specific workplace postural interventions are unlikely to reduce the risk of upper extremity musculoskeletal symptoms among computer users
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 .
Background Little is known about the most effective occupational health and safety ( OHS ) interventions to reduce  upper extremity musculoskeletal disorders ( MSDs ) and injuries .
Methods A systematic review used a best evidence synthesis approach to address the question : “ do occupational health and safety interventions have an effect on upper extremity musculoskeletal symptoms , signs , disorders , injuries , cl aims and lost time ? ”