Iranian Journal of Ergonomics

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Introduction: Musculoskeletal disorders (MSDs) are the main causes of work related injuries and disabilities in developed as well as developing countries. Few studies have considered different interactive effects of individual and work-related factors on MSDs, simultaneously. Methods and Materials: Data were gathered by Nordic questionnaire and Quick Exposure Check (QEC) method and were analyzed using logistic regression model in order to study the correlation between the prevalence and intensity of MSDs and individual and work-related factors. Results: More than half of all participants (61.6%) reported suffering from one form of MSDs during the past 6 months. Results showed that risk factors such as work stress, sleeping position, lifestyle and poor posture had an important role in the prevalence and intensity of MSDs. Discussion: The effect of a risk factor is constantly in interaction with other risk factors, and is modified by other factors. Participatory ergonomic intervention programs, work station intervention, ergo stress intervention and life-style interventions were suggested in order to decrease the prevalence and intensity of MSDs.

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Introduction: The introduction of a thematic framework is necessary for the field of ergonomics and human factors. Content analysis is a useful tool for the trend analysis and distribution of published articles however, reports on the content analysis of ergonomics journals are rare. The present study was conducted to identify research trends in the journal of Human Factors through a content analysis of its recent articles published over the past ten years (2005-2014).

Materials and Methods: The present study used the directed content analysis method. Two analysis experts classified 741 articles based on their thematic codes. A conceptual framework was used to perform the content analysis. EXCEL 2007 and SPSS-19 were used for the data preparation, theme distribution and trend analysis of the published themes.

Results: From the total of 21 themes extracted, six themes defined over 50% of the variance in the published articles, including “Biomechanics, Anthropometry and Work Physiology", "Display and Control Design", "Surface Transportation Systems", "Cognitive Processes", "Attentional Processes" and "Sensory, Perceptual and Psychomotor Processes". The journal had a special focus on "Biomechanics, Anthropometry and Work Physiology" (about 12%). 

Conclusion: The thematic framework and distribution pattern noticed in this study can be used for planning education and research on human factors and ergonomics in universities, research centers and related organizations.

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Introduction: Metro driving is one of the newest jobs in Iran. Due to the lack of studies about train drivers’ workload, there is no comprehensive information about factors that effect workload. This study aimed at analyzing the factors that may effect driver workload, in order to recommend control measures.

Methods: In this mixed method study, data generation was done through field observations, document reviews, individual interviews, focus group interviews, and focus group discussions. In order to perform field data collection, the institute for occupational ergonomics and CCD Design and Ergonomics Ltd’s developed tools were used. Directed content analysis was used for qualitative data analysis.

Results: Overall, 65 factors were extracted as the factors that may effect driver workload. The extracted factors were drawn on a fishbone diagram, over 8 categories, including management, supervision and organizational climate, infrastructure, job design, journey, and environmental as distal factors and time pressure, information exchanges, and individual factors as proximal factors.

Conclusions: Some of the distal factors are the nature of an urban transport system, so the only amendment is compensatory programs, and some of them could be resolved by long-term plans. Workload of train drivers could be reduced with a focus on the proximal factors in the short-term, and the distal factors in the long-term.

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Background and Objectives: Musculoskeletal disorders cause about half of all work-related disease, and are the major cause of loss of time, increased costs, and labor injury. This study aims to evaluate the workload and its association with the prevalence of wrist disorders. It was carried out in the assembly workers of a manufacturing industry.
Methods: This cross-sectional study was conducted among 120 female workers employed. Theit mental workload, physical workload and prevalence of wrist MSDs were evaluated using the NASA-TLX, the OCRA method and the Nordic wrist and hand scan questionnaire respectively.
Results: The NASA-TLX showed that the physical demands and effort with mean scores of 78.79 and 78.37 were respectively the most important subjective mental workload (SMWL) scale. Also The results on the basis of the OCRA risk level showed that the highest right-hand risk was at risk level 3 and the highest left-hand risk was at risk level 1 .The Statistical analysis showed that OCRA risk levels and mean scale physical demands and efforts were significantly higher in those with wrist pain than those without pain (P<0.05).There was a direct correlation between the severity of the wrist pain with the OCRA risk index in both hands (P=0.001) and the total score of NASA (r=0.232, P<0.05).
Conclusion: It was revealed that mental load was high in assembly lines of the manufacturing industry and this result was also confirmed by physical evaluation. This study indicated that overall score of SMWL can affect the incidence of MSDs. That is why mental workload should be considered as a risk factor for MSDs.

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Background and Objectives: Macro Ergonomics is a socio-technical approach that deals with organizational, and work system design, as well as the design of human-machine, human-environment, and human-job interactions. Researches show that workplace macroeconomic’ conditions have undesirable effects on employees’ health, and hospital staff experience high levels of occupational stress and high prevalence of musculoskeletal disorders. This study aimed to investigate the relation between macroeconomic’ condition and prevalence of musculoskeletal disorders as well as outcomes of job stress among employees of hospitals affiliated to Urmia University of Medical Sciences.
Methods: This study was a descriptive cross-sectional study and 350 employees who randomly were selected from 5 hospitals participated in this study. Macro-ergonomic, Nordic and job stress outcomes questionnaires were used for data collection. Descriptive statistics, ANOVA and Chi-square tests were applied for data analysis.
Results: The findings of the present study indicated that out of 350 participants 217 (62%) were female and 168 were nurses (48%). Their mean age was 36.63 (±8.13) years and their average work experience was 11.53 (±7.65) years. The results of ANOVA test showed that the status of macro-ergonomics was significantly different in hospitals and hospital 1 had favorable condition. The majority of musculoskeletal disorder symptoms were reported in the neck (75.7%), hip, and waist (73.7%). The average score of job stress outcomes for the participants was lower than favorable limit. Macro-ergonomic’ conditions had significant associations with musculoskeletal disorders and job stress’ outcomes.
Conclusion: Based on the results of the current study, macro-ergonomic conditions had significant effects on musculoskeletal disorders and job stress outcomes. Interventional efforts should focus on organization and developing macro-ergonomic training programs to reduce musculoskeletal disorders and job stress and improve job conditions in hospitals.

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