Predicting Forearm Physical Exposures During Computer Work Using Self-Reports, Software-Recorded Computer Usage Patterns, and Anthropometric and Workstation Measurements

Cost and statistical efficiency of posture assessment by inclinometry and observation, exemplified by paper mill work

Postures at work are paramount in ergonomics. They can be determined using observation and inclinometry in a variety of measurement scenarios that may differ both in costs associated with collecting and processing data, and in efficiency, i.e. the precision of the eventual outcome. The trade-off between cost and efficiency has rarely been addressed in research despite the obvious interest of obtaining precise data at low costs. Median trunk and upper arm inclination were determined for full shifts in 28 paper mill workers using both observation and inclinometry. Costs were estimated using comprehensive cost equations; and efficiency, i.e. the inverted standard deviation of the group mean, was assessed on basis of exposure variance components. Cost and efficiency were estimated in simulations of six sampling scenarios: two for inclinometry (sampling from one or three shifts) and four for observation (one or three observers rating one or three shifts). Each of the six scenarios was evaluated for 1 through 50 workers. Cost-efficiency relationships between the scenarios were intricate. As an example, inclinometry was always more cost-efficient than observation for trunk inclination, except for observation strategies involving only few workers; while for arm inclination, observation by three observers of one shift per worker outperformed inclinometry on three shifts up to a budget of €20000, after which inclinometry prevailed. At a budget of €10000, the best sampling scenario for arm inclination was 2.5 times more efficient than the worst. Arm inclination could be determined with better cost-efficiency than trunk inclination. Our study illustrates that the cost-efficiency of different posture measurement strategies can be assessed and compared using easily accessible diagrams. While the numeric examples in our study are specific to the investigated occupation, exposure variables, and sampling logistics, we believe that inclinometry will, in general, outperform observation. In any specific case, we recommend a thorough analysis, using the comparison procedure proposed in the present study, of feasible strategies for obtaining data, in order to arrive at an informed decision support.

The Effects of Standing Working Posture on Operation Force and Upper Limb Muscle Activation When Using Different Pointing Devices

This study investigated how sitting and standing working postures affected operation force, upper limb muscle activation, and task performance using different pointing devices. Fifteen male participants completed cursor aiming and dragging tasks using a conventional mouse, a vertical mouse, and a trackball at sitting and standing workstations. A custom-made force plate was used to measure operation forces applied to the pointing devices. Surface electromyography (EMG) was used to capture the activation of the biceps brachii, triceps brachii, deltoid, and trapezius. Task performance was measured by task success rates, and subjective ratings were obtained for the force required for operation, smoothness of operation, accuracy, and local fatigue in the upper limb. We quantified the following significant outcomes: (1) greater operation forces were found when standing; (2) standing reduced EMG amplitudes of the triceps and trapezius muscles for all tasks; (3) during the aiming task, the vertical mouse had greater operation forces; (4) during the dragging task, both the vertical mouse and trackball had greater operation forces; and (5) task success rates differed for pointing devices only when sitting. This study revealed the distinct biomechanical properties of standing working posture and suggested limited beneficial effects of alternative pointing devices in terms of task performance and subjective ratings.

Association between comprehensive workstation and neck and upper-limb pain among office worker

OBJECTIVES

Our study aimed to investigate the association between comprehensive workstations and neck and upper-limb pain (NUP) among office workers.

METHODS

This cross-sectional study included 307 office workers (median age, 39 years; 88% men). Workstations (presence of armrest, armrest position, number of monitors used, mouse position, mouse usage, keyboard usage, and keyboard position) were investigated in terms of 17 items and judged as "adequate" or "inadequate." NUP was assessed using a numerical rating scale. NUP locations included the neck, shoulder, elbow, and wrist. In the statistical analysis, outcome variables were the presence of pain in each part, while explanatory variables were the number of inadequate workstations. Logistic regression analyses were conducted with adjustment for age, gender, working duration, and exercise habit.

RESULTS

The prevalence of neck pain was 47% (n = 143), shoulder pain was 50% (n = 153), elbow pain was 7.2% (n = 22), and wrist pain was 13% (n = 40). In the adjusted model, the number of inadequate workstations had significant positive associations with elbow pain (odds ratio [OR], 1.39; 95% confidence interval [CI], 1.06.1.81) and wrist pain (OR, 1.80; 95% CI, 1.17.2.26). However, the number of inadequate workstations was not significantly associated with neck pain or shoulder pain.

CONCLUSIONS

Workstation-related factors (presence of armrest, armrest position, mouse usage, and keyboard usage) were significantly associated with elbow and wrist pain. Our findings suggest that workstations can contribute to elbow and wrist pain in office workers.

Factors associated with caregiver burden among adult (19-64 years) informal caregivers - An analysis from Dutch Municipal Health Service data

Due to the ageing population and the rising prevalence of chronic diseases, it is expected that the demand on informal caregivers will increase. Many informal caregivers experience burden, which can have negative consequences for their own health and that of the care recipient. To prevent caregiver burden, it is important to investigate factors associated with this burden. We aimed to identify factors associated with caregiver burden in adult informal caregivers. Among a sample of adult informal caregivers (n = 1,100) of the Dutch region of Zaanstreek-Waterland, perceived caregiver burden, demographic factors, caregiving situation, health-related factors and socio-financial factors were measured as part of the national Health Survey in 2016. Using univariate and multivariate logistic regression analysis, for which a backward selection method was applied, associations with caregiver burden were studied. In the multivariate model, time spent providing informal care was significantly associated with perceived caregiver burden, with an odds ratio (OR) [95% confidence interval] of 7.52 [3.93-14.39] for those spending >16 hr compared to 1-2 hr on informal care. Also providing care to their child(ren) (OR: 2.55 [1.51-4.31]), poor perceived health (OR: 1.80 [1.20-2.68]) and loneliness of the caregiver (OR: 2.05 [1.41-2.99]) were significantly associated with caregiver burden. To possibly prevent and reduce informal caregiver burden, factors associated with such burden should be intervened on. As such, special attention should be paid to caregivers who provide many hours of care or provide care to their child(ren), as well as those who have a poor perceived health themselves and/or experience feelings of loneliness.

Demands for multidimensional information on the work environment: A methodological framework for regular studies

BACKGROUND

Development of methodologies for making economic decisions on designing work environment studies is a theoretical challenge for researchers in occupational health sciences. There are well-defined tools available in the relevant literature for analysis of cost-efficiency associated with the assessment of an occupational exposure of interest. However, these analytical tools are not appropriate for holistic studies of the work environment as a multidimensional reality.

OBJECTIVE

This article introduces an appropriate methodology for designing cross-sectional comprehensive studies of the work environment, in order to optimize the production of information on the psychosocial, ergonomic, and physical dimensions of the work environment in regular studies.

METHODS

The employment of a translog cost-utility function is suggested as a suitable way to provide cost-minimized designs for regular studies which are aimed at providing or developing multidimensional information systems of the work environment.

RESULTS

The translog cost-utility function is not subject to predetermined restrictions, but has a flexibility property allowing it to be transformed to any specification that is adaptable to the specific work environmental characteristics and research requirements.

CONCLUSION

The translog cost-utility function is an appropriate econometric model for optimizing the production of multidimensional information on occupational exposures in regular cross-sectional workplace studies.