Iranian Journal of Ergonomics

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Introduction: Bank staff experience high level of job stress due to the nature of their work. One of the consequences of stress is its impact on job performance. Since the internal studies in this area are relatively rare, this study was conducted to investigate the relationship between the psychosocial stressors and job performance among bank staff. Materials and Methods: All staff of the bank branches participated in this study. The General Nordic Questionnaire and Human Resource Productivity Questionnaire were used for data collection. The correlation coefficient and regression models were employed to examine the relationship between job stressors and their scales as independent variables and job performance as the dependent variable. Furthermore, in order to accurately assess the relations between variables, structural equation models were utilized. Results: The results revealed that the prevalence of stress among bank staff was in moderate level (46.6%). Meanwhile, there was a negative and significant relationship between stress in "task domain" and "socio-organizational domain" and job performance. Among the measures in socio-organizational domain, organizational culture and leadership showed highly negative and significant relationships with job performance (p= 0.001). Conclusion: According to the obtained results, socio-organizational domain can be considered as the main cause of loss of productivity. Hence, it is suggested to make further attempts to control the psychosocial factors in workplaces and avoid performance deterioration, particularly in organizational culture and leadership measures.

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Background: Patient Manual handling is one of the major risk factors in musculoskeletal disorders among healthcare workers (HCWs). Therefore, the purpose of this study was to estimate the mechanical force on the low back of the staff responsible for patient manual handling and to exam in the effect of patient manual handling by two people on the level forces exerted on HCWs ҆ low back. methods: the participants of this study were 10 health care workersdoing patient manual handling individually and by two people . To determine the posture of these people, we filmed them both from front and side and force plate was used to determine the weight of the patient handling by HCWs. 3DSSPP was used to estimate theforces exerted on the their low back during patient manual handling. Results: Results showed that among the four studied tasks, the maximum compression forces exerted on discs L4/L5 and L5/S1 were 3591 ± 863 and 3342 ± 827 respectively when the patient was seated on wheelchair. The Maximum shear force exerted on the disc L4/L5 and L5/S1 were 252 ± 122 432 ± 36 N respectively when patient was seated on the bed. No significant difference was seen in the average forces exerted on low back except seating patient on wheelchair. ( P> 0.05) Conclusions: The comparison of exerted force on disks with recommended limits revealed that only the task of placing patient on wheelchair exerted force on low back exceed NIOSH recommended weight limit. patient manual handling by two people most tasks of this study does not created significant difference. Therefore to reduce exert force on low back need ergonomic intervention including bed design, beds appropriate stabilization, training.

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Introduction: Adaptive performance is defined as an employee’s ability to deal with changes and new and unusual situations in the workplace. The present study mainly focused on factor analysis of the Adaptive Performance Scale (APS) and determining its validity and reliability. Adaptive performance is a multi-dimensional structure with five latent factors.

Materials and Methods: This method validation study was conducted in Ahvaz, Iran. 210 randomly selected public hospital nurses completed the Persian version of the APS. Exploratory factor analysis (varimax rotation) was used to explore the factor structure of the scale. Confirmatory factor analysis and structural equation modeling were applied to fit the model.

Results: The overall reliability of the APS was confirmed (Cronbach’s alpha = 0.89). Factor analysis was used to evaluate the factor structure of the scale. Kaiser-Meyer-Olkin index (0.88) and Bartlett's sphericity test result (1639.093) were both significant. Finally, varimax rotation showed all items to have significant factor loadings.

Conclusion: Our findings confirmed the acceptable psychometric properties (reliability and validity) of the APS for administration among nurses. Therefore, the adaptive performance construct contains five distinct dimensions, namely dealing with emergency and unexpected situations, work stress management, creative problem solving, learning, and interpersonal adaptability. These results are consistent with previous studies.

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Background: Power and pinch hand grip strengths are major clinical and ergonomic parameters contributing to the hand muscle power. The data on hand grip strength measurements can have many benefits, including application in the design of hand tools. The present study was conducted to measure power hand grip strength among male and female students aged 19 to 36 using a Jamar Dynamometer and to compare their measurement data with the data obtained from other groups of the population.

Materials and Methods: The present cross sectional study was conducted on 234 male and female students aged 19-36 in Urmia University of Medical Sciences. Hand grip strength was measured using Jamar hand dynamometer and according to the Southampton protocol for adult grip strength measurement.

Results: The mean (±standard deviation of) hand grip strength calculated was 44.39 (±9.71) in the male students 20.48 (±5.86) in the female students. A high correlation was observed between the power hand grip strength in the left and right hands (r=0.94 and P<0.001) and a significant difference then between the power hand grip strength in the dominant and non-dominant hands. 

Conclusion: The findings of the present study and similar studies about power hand grip strength in the Iranian population can be used by ergonomists and manufacturers to improve the design of hand tools and the performance of tasks requiring hand muscle power.

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Introduction: Foot anthropometric dimensions could be useful in designing comfortable footwear. The objective of this study was the measurement of foot anthropometric dimensions in a group of students.

Methods: This was a descriptive study in which 21 dimensions of foot for 580 males and females were measured manually. To measure the foot dimensions, a digital caliper and a tape were used. The measured dimensions included the important lengths, widths, heights and girths of foot. Descriptive statistics such as percentiles, mean and standard deviation were calculated for the collected data. To test and survey of the mean of foot dimensions between males and females, statistics such as independent t-test and effect size (Cohen’s d) were used.

Results: The values of mean, standard deviation, the 5th, 50th, and 95th percentiles were calculate and tabulated for the total studied population and for gender. In all measured foot dimensions, males had bigger dimensions than females. Gender had different impacts on the measured foot dimensions. The mean of all foot dimensions was significantly different between males and females (P value = 0.001). Digital pattering of I and II were observed in 78% and 22% of the studied population, respectively.

Conclusions: In the present study, important anthropometric data of foot were collected for a group of students. The presented percentiles could be used in design of male and female shoes. Conducting similar studies in children with different age categories could help completion of the anthropometric database.

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Introduction: Psychosocial factors and fatigue are significant factors in nurses’ performance. Since the relationship between psychosocial factors and fatigue has been rarely studied, the aim of this study was investigating the relationship between psychosocial work factors and fatigue among nurses.
Method: In this cross-sectional study, 270 nurses from hospitals of Urmia University of Medical Sciences randomly participated. The Job Content Questionnaire and Swedish Occupational Fatigue Inventory were used for data collection. Pearson’s correlation coefficient and Structural Equation Modeling were used for data analysis.
Results: The mean (SD) of control was 66.32 (7.36), psychological job demand 35.47 (3.68), social support 22.31 (2.64), physical job demand 15.22 (2.18), and job insecurity 8.72 (4.06). Control and social support dimensions had low levels. Moreover, psychological and physical job demand had high levels, which indicates a high stress level. According to the results, psychological and physical job demand had a significant relationship with all dimensions of fatigue (P < 0.001).
Conclusions: The majority of nurses were exposed to high levels of job stress. Among psychosocial factors, physical demand was identified as the most effective factor on fatigue. Any comprehensive interventional program regarding psychosocial work factor in order to reduce job stress and fatigue can improve health care quality and also prevent medical errors.
 

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