Objectives This systematic review aimed to identify published observational methods assessing biomechanical exposures in occupational settings and evaluate them with reference to the needs of different users. MethodsWe searched scientific databases and the internet for material from 1965 to September 2008. Methods were included if they were primarily based on the systematic observation of work, the observation target was the human body, and the method was clearly described in the literature. A systematic evaluation procedure was developed to assess concurrent and predictive validity, repeatability, and aspects related to utility. At least two evaluators independently carried out this evaluation. ResultsWe identified 30 eligible observational methods. Of these, 19 had been compared with some other method(s), varying from expert evaluation to data obtained from video recordings or through the use of technical instruments. Generally, the observations showed moderate-to-good agreement with the corresponding assessments made from video recordings; agreement was the best for large-scale body postures and work actions. Postures of wrist and hand as well as trunk rotation seemed to be more difficult to observe correctly. Intra-and inter-observer repeatability were reported for 7 and 17 methods, respectively, and were judged mostly to be moderate or good.good. . ConclusionsWith training, observers can reach consistent results on clearly visible body postures and work activities. Many observational tools exist, but none evaluated in this study appeared to be generally superior. When selecting a method, users should define their needs and assess how results will influence decision-making.

VEIERSTED KB, WESTGAARDRH, ANDERSEN P. Electromyographic evaluation of muscular work pattern as a predictor of trapezius myalgia. Scand J Work En viron Health 1993;19:284-90. Electromyographic (EMG) measurements and interviews concerning muscular pain and disability were performed prospectively every 10th week on 30 healthy new female employees of a chocolate manufacturing plant. The static muscle activity and rate of short unconscious interruptions in EMG activity (EMG gaps) of the trapezius muscle during repetitive work tasks were evaluated as possible risk factors for patient status with trapezius myalgia. At the start of employment, the static and median contraction levels were significantly higher in future patients than in the rest of the subjects (nonpatients). In subsequent recordings these values were reduced to the level of the nonpatients. Throughout the study, the future patients had a lower frequency of EMG gaps than the nonpatients. A regression analysis showed a significant value for a low rate of EMG gaps to predict future patient status.Key terms: muscle activity pauses, neck and shoulder disorder, prospective design, repetitive work load, static work load.Occupations with maintained po stures and repetiti ve work tasks are commonly coupled to a high pre valence of neck and shoulder di so rders ( I , 2). Crosssectional studies have shown that pat ients with trapezius myalgia use their muscles at a higher static level than healthy subj ec ts do (3-5). Subjects who ha ve suffered mu scle pain on a previou s occasion, but not during a recording sess ion, have also shown a higher static electromyographic (EMG) level than subj ec ts without sy mptoms (6) . Subjects who hav e experienced muscular pa in ha ve dem onstrated fewer short, uncon sc iou s interruptions in EMG activ ity (EM G "gaps," with a duration of 0.2-2 s) during repetitive work task s than healthy subjects (6). A previous prospective study of the relation bet ween muscular effort during work and subs eque nt pain used video recordings as indirect measurements of mu scle lo ad (7). It found th at relative time with elevated shoulders and a flexed neck was a risk fa ctor.Th e present report is the fir st pr ospecti ve study wi th direct measurements of oc cupati onal mu scular activi ty and an asse ssment of mu scular pain. The development of mu scular pain and subjectively assessed risk factors for trapezius myalgia among workers with rep etitive light manu al wor k in the sa me manufacturing plant ha ve been described elsewhere (2, 8). 284Th e main purpose of thi s paper was to analyze the ass ocia tion between the le vel and pattern of mu scl e usage du ring the performance of a stereotyped job and the development of trapezius myalgia. Subjects and methods Subje ctsFifty-five fem ale workers hired consec utively by a chocolate manufacturing company were included in the study as the y started their employ me nt. Except for three subjects who declined to participate , all of the subjects signed an in formed consent form. The study was ...

BackgroundThis review examines the evidence for an association between computer work and neck and upper extremity disorders (except carpal tunnel syndrome).MethodsA systematic critical review of studies of computer work and musculoskeletal disorders verified by a physical examination was performed.ResultsA total of 22 studies (26 articles) fulfilled the inclusion criteria. Results show limited evidence for a causal relationship between computer work per se, computer mouse and keyboard time related to a diagnosis of wrist tendonitis, and for an association between computer mouse time and forearm disorders. Limited evidence was also found for a causal relationship between computer work per se and computer mouse time related to tension neck syndrome, but the evidence for keyboard time was insufficient. Insufficient evidence was found for an association between other musculoskeletal diagnoses of the neck and upper extremities, including shoulder tendonitis and epicondylitis, and any aspect of computer work.ConclusionsThere is limited epidemiological evidence for an association between aspects of computer work and some of the clinical diagnoses studied. None of the evidence was considered as moderate or strong and there is a need for more and better documentation.

Standardized and machine-paced work tasks at a packing machine were examined to evaluate interindividual variability of muscle activity patterns. Ten trained female workers, without musculo-skeletal complaints at the time of the recording, performed the work tasks while electromyographic (EMG) recordings were obtained from both upper trapezius muscles. Static muscle activity and periods of between 0.2 and 2 s duration with low muscle activity, EMG gaps, were analysed. Complaints of muscular fatigue, soreness or pain in the neck and shoulders during the last 12 months were recorded. The level of static muscle activity was 1.6 (range 0.4 to 2.5) per cent of maximal voluntary contraction and median number of EMG gaps was 4.8 (range 0.8 to 20) per minute. Workers with previous episodes of complaints (five subjects) had higher levels of static muscle activity and fewer EMG gaps than workers without such episodes (p less than 0.05, Wilcoxon 2-sample test, one-tailed). Considerable interindividual variability of muscle activity patterns was found in spite of stereotyped work. No causal relations may be inferred from the correlation between the level of trapezius activity and complaints, though it indicates that individual, inexpedient muscle activity patterns may constitute an important risk factor for development of musculo-skeletal complaints.

BackgroundA systematic attempt to summarize the literature that examines working conditions and occupational health among immigrant in Europe and Canada.MethodsWe established inclusion criteria, searched systematically for articles included in the Medline, Embase and Social Sciences Citation Index databases in the period 2000–2016 and checked the reference lists of all included papers.ResultsEighty-two studies were included in this review; 90% were cross-sectional and 80% were based on self-report. Work injuries were consistently found to be more prevalent among immigrants in studies from different countries and in studies with different designs. The prevalence of perceived discrimination or bullying was found to be consistently higher among immigrant workers than among natives. In general, however, we found that the evidence that immigrant workers are more likely to be exposed to physical or chemical hazards and poor psychosocial working conditions is very limited. A few Scandinavian studies support the idea that occupational factors may partly contribute to the higher risk of sick leave or disability pension observed among immigrants. However, the evidence for working conditions as a potential mediator of the associations between immigrant status and poor general health and mental distress was very limited.ConclusionSome indicators suggest that immigrant workers in Europe and Canada experience poorer working conditions and occupational health than do native workers. However, the ability to draw conclusions is limited by the large gaps in the available data, heterogeneity of immigrant working populations, and the lack of prospectively designed cohort studies.Electronic supplementary materialThe online version of this article (10.1186/s12889-018-5703-3) contains supplementary material, which is available to authorized users.