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 field study of supplementary rest breaks for data-entry operators
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
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 ? ”