@article{noack-cooper_sommerich_mirka_2009, title={College students and computers: Assessment of usage patterns and musculoskeletal discomfort}, volume={32}, ISSN={["1875-9270"]}, DOI={10.3233/WOR-2009-0827}, abstractNote={A limited number of studies have focused on computer-use-related MSDs in college students, though risk factor exposure may be similar to that of workers who use computers. This study examined computer use patterns of college students, and made comparisons to a group of previously studied computer-using professionals. 234 students completed a web-based questionnaire concerning computer use habits and physical discomfort respondents specifically associated with computer use. As a group, students reported their computer use to be at least 'Somewhat likely' 18 out of 24 h/day, compared to 12 h for the professionals. Students reported more uninterrupted work behaviours than the professionals. Younger graduate students reported 33.7 average weekly computing hours, similar to hours reported by younger professionals. Students generally reported more frequent upper extremity discomfort than the professionals. Frequent assumption of awkward postures was associated with frequent discomfort. The findings signal a need for intervention, including, training and education, prior to entry into the workforce. Students are future workers, and so it is important to determine whether their increasing exposure to computers, prior to entering the workforce, may make it so they enter already injured or do not enter their chosen profession due to upper extremity MSDs.}, number={3}, journal={WORK-A JOURNAL OF PREVENTION ASSESSMENT & REHABILITATION}, author={Noack-Cooper, Karen L. and Sommerich, Carolyn M. and Mirka, Gary A.}, year={2009}, pages={285–298} }
 @article{bajaj_mirka_sommerich_khachatoorian_2006, title={Evaluation of a redesigned self-checkout station for wheelchair users}, volume={18}, ISSN={["1040-0435"]}, DOI={10.1080/10400435.2006.10131903}, abstractNote={Self-checkout is the emergent/emerging retail technology wherein users (shoppers) check out their own items using an interactive kiosk. A dramatic growth is anticipated in the prevalence of self-checkout systems in retail environments. A study was conducted to develop and evaluate a redesign of a self-checkout system with a focus on issues related to physical accessibility for wheelchair users. Two checkout station prototypes were built: a full-scale model of an existing system and a full-scale model of a system with design modifications (e.g., inclusion of appropriate wheelchair clearance under the workstation, reduced vertical position of the credit card reader, etc.). Five wheelchair users and 10 non–wheelchair users performed simulated self-checkout activities using both workstations. The principal independent variable was workstation type (standard design vs. modified design). The dependent measures were productivity (time to complete a transaction), shoulder flexion angle, torso flexion angle, and the user's subjective assessment of the experience. The results of this study indicate that workstation type did not influence productivity levels in either participant group (wheelchair users or non–wheelchair users). Posture, on the other hand, was significantly improved: the peak shoulder angle was reduced by 64% in wheelchair users and by 69% in the non–wheelchair user group. Peak flexion angle of the torso was also reduced by 67% for wheelchair users. Subjective feedback from the wheelchair user group supported the postural data by showing an overall preference for the redesigned workstation, whereas the non–wheelchair group showed no preference between the two. These results indicate that design for populations with specific limitations does not need to come at a cost of reduced accessibility for persons without these limitations; universal design is achievable.}, number={1}, journal={ASSISTIVE TECHNOLOGY}, author={Bajaj, K and Mirka, GA and Sommerich, CM and Khachatoorian, H}, year={2006}, pages={15–24} }
 @article{joines_sommerich_mirka_wilson_moon_2006, title={Low-level exertions of the neck musculature: A study of research methods}, volume={16}, ISSN={1050-6411}, url={http://dx.doi.org/10.1016/j.jelekin.2005.09.007}, DOI={10.1016/j.jelekin.2005.09.007}, abstractNote={Musculoskeletal neck discomfort is prevalent in many occupations and has been the focus of much research employing surface electromyography (sEMG). Significant differences in experimental methods among researchers make comparisons across studies difficult. The goal of the current research was to use empirical methods to answer specific methodological questions concerning use of sEMG in evaluation of the neck extensor system. This was accomplished in two studies. In Experiment 1, ultrasound technology was used to: (a) determine accessibility of m. splenius and semispinalis capitis with surface electrodes, (b) identify appropriate electrode locations for these muscles/muscle groups, and (c) illustrate potential benefits of using ultrasound in locating muscles/placing electrodes. Experiment 2 sought to assess effects of posture when normalizing sEMG data. Results from Experiment 1 showed no direct access to semispinalis capitis for surface electrodes; their activity can only be sampled as part of a group of muscles. In most subjects, m. splenius was found to be accessible to surface electrodes. Electrode placement recommendations are provided. Results of Experiment 2 showed significant differences in normalized EMG data between a posture-specific technique and a reference posture technique. Posture-specific normalization is recommended for accurately assessing the relative intensity of contractions of these muscles.}, number={5}, journal={Journal of Electromyography and Kinesiology}, publisher={Elsevier BV}, author={Joines, Sharon M.B. and Sommerich, Carolyn M. and Mirka, Gary A. and Wilson, James R. and Moon, Samuel D.}, year={2006}, month={Oct}, pages={485–497} }
 @article{leyman_mirka_kaber_sommerich_2004, title={Cervicobrachial muscle response to cognitive load in a dual-task scenario}, volume={47}, ISSN={["1366-5847"]}, DOI={10.1080/00140130310001629766}, abstractNote={People working in an office environment often have to deal with significant cognitive workload due to the coordination of multiple, simultaneous tasks. The objective of this research was to examine the impact of cognitive load in office-type tasks on physical-stress response, using a dual-task paradigm involving a primary cognitive task and secondary typing task. The central hypothesis of this research was that altering the demands of the cognitive task would lead to a difference in physical stress-level and performance. Cognitive load was manipulated by presenting participants with three different types of cognitive tasks described in Rasmussen's (1983) taxonomy, including skill-, rule-, and knowledge-based tasks. Dependent variables examined in the study included: (1) electromyographic activity of the upper trapezius (pars descendens) and cervical erector spinae muscles, (2) performance in a secondary typing task, and (3) subjective measures of stress and cognitive workload. The results of this study revealed that the primary task causing the highest level of perceived workload also produced 61% higher muscle activity in the right trapezius, and 6 and 11% higher activity in the left and right cervical erector spinae, respectively, in comparison to muscle activity associated with the cognitive task causing the lowest perceived workload. With respect to performance, a 23% decrease was observed in typing productivity when the rule-based task was completed simultaneously vs. typing in the absence of any additional cognitive task (the baseline condition). This information may be used to better organize work activities in office environments to increase performance and reduce stress.}, number={6}, journal={ERGONOMICS}, author={Leyman, ELC and Mirka, GA and Kaber, DB and Sommerich, CM}, year={2004}, month={May}, pages={625–645} }
 @article{duke_mirka_sommerich_2004, title={Productivity and ergonomic investigation of bent-handle pliers}, volume={46}, ISSN={["1547-8181"]}, DOI={10.1518/hfes.46.2.234.37341}, abstractNote={ Awkward wrist posture is generally considered an occupational risk factor for hand/wrist disorders, leading to the ergonomic design principle of “bend the tool, not the wrist.” Sixteen participants performed a computer jumper installation task and a simple assembly task while productivity, wrist posture, and shoulder posture were measured. The work surface orientation (vertical and 45°) and the level of constraint placed on the user (constrained grip and unconstrained grip) were also varied. The results indicate that the beneficial effects of the bent-handle pliers are task dependent. In the computer jumper task the bent-handle pliers resulted in 5.3% faster task performance, whereas in the assembly task performance was 4.9% faster with the straight-handle pliers. The bent-handle pliers reduced shoulder deviations by 50% in the jumper installation task, and ulnar deviation was reduced by 12% and 22% for the jumper installation task and the assembly task, respectively (all significant at p < .05). However, allowing participants to hold the pliers in a grip configuration of their choosing (unconstrained technique) often reduced these postural benefits. In applying these results to work place design activities, one should recognize that the ergonomic utility of benthandle pliers can be considerable but that the 3-D kinematics characteristics of the task must be considered. }, number={2}, journal={HUMAN FACTORS}, author={Duke, K and Mirka, GA and Sommerich, CM}, year={2004}, pages={234–243} }
 @article{smith_sommerich_mirka_george_2002, title={An investigation of ergonomic interventions in dental hygiene work}, volume={33}, number={2}, journal={Applied Ergonomics}, author={Smith, C. A. and Sommerich, C. M. and Mirka, G. A. and George, M. C.}, year={2002}, pages={175–184} }
 @article{sommerich_starr_smith_shivers_2002, title={Effects of notebook computer configuration and task on user biomechanics, productivity, and comfort}, volume={30}, ISSN={["0169-8141"]}, DOI={10.1016/S0169-8141(02)00075-6}, abstractNote={This study took a comprehensive approach to evaluating effects of using a notebook computer stand-alone or along with inexpensive peripheral input devices. The study examined effects on biomechanics, productivity, and discomfort, and considered the impact of both computer configuration and task performed. It was hypothesized that, in general, the stand-alone configuration would induce greater postural fixity and more non-neutral postures than configurations with peripheral input devices. Dependent measures included muscle activity, posture and posture variation/fixity, productivity, and subjective assessments of discomfort and preference. The data were generally consistent with the hypothesis, though some biomechanical advantages were identified for each configuration; specifics and exceptions are discussed, along with reasons for a general recommendation for the use of an external mouse, or mouse and keyboard (without number pad) when using a notebook computer for an extended period of time, as in a desktop replacement scenario. Notebook computer use is rapidly increasing, in industry and schools. Yet the notebook form factor is inconsistent with a number of current design recommendations. Little research concerning physical ergonomics of notebook computer use has been conducted, so recommendations for use are currently limited and not strongly supported by objective evidence.}, number={1}, journal={INTERNATIONAL JOURNAL OF INDUSTRIAL ERGONOMICS}, author={Sommerich, CM and Starr, H and Smith, CA and Shivers, C}, year={2002}, month={Jul}, pages={7–31} }
 @article{psihogios_sommerich_mirka_moon_2001, title={A field evaluation of monitor placement effects in VDT users}, volume={32}, ISSN={["0003-6870"]}, DOI={10.1016/S0003-6870(01)00014-X}, abstractNote={Appropriate visual display terminal (VDT) location is a subject of ongoing debate. Generally, visual strain is associated with higher placement, and musculoskeletal strain is associated with lower placement. Seeking resolution of the debate, this paper provides a comparison of results from previous lab-based monitor placement studies to recommendations and outcomes from viewing preference and neutral posture studies. The paper then presents results from a field study that addressed two outstanding issues: Does monitor placement in a workplace elicit postures and discomfort responses similar to those seen in laboratory settings? Results showed placements in the workplace elicited postures similar to those in lab studies. Additionally, preferred VDT location generally corresponded to the location in which less neck discomfort was reported, though that trend requires further investigation. Overall, there seems to be consistent evidence to support mid-level or somewhat higher placement, as a rule-of-thumb, considering preferred gaze angle and musculoskeletal concerns. However, optimal placement may be lower for some individuals or tasks.}, number={4}, journal={APPLIED ERGONOMICS}, author={Psihogios, JP and Sommerich, CM and Mirka, GA and Moon, SD}, year={2001}, month={Aug}, pages={313–325} }
 @article{kelaher_nay_lawrence_lamar_sommerich_2001, title={An investigation of the effects of touchpad location within a notebook computer}, volume={32}, ISSN={["1872-9126"]}, DOI={10.1016/S0003-6870(00)00020-X}, abstractNote={This study evaluated effects of the location of a notebook computer's integrated touchpad, complimenting previous work in the area of desktop mouse location effects. Most often integrated touchpads are located in the computer's wrist rest, and centered on the keyboard. This study characterized effects of this bottom center location and four alternatives (top center, top right, right side, and bottom right) upon upper extremity posture, discomfort, preference, and performance. Touchpad location was found to significantly impact each of those measures. The top center location was particularly poor, in that it elicited more ulnar deviation, more shoulder flexion, more discomfort, and perceptions of performance impedance. In general, the bottom center, bottom right, and right side locations fared better, though subjects' wrists were more extended in the bottom locations. Suggestions for notebook computer design are provided.}, number={1}, journal={APPLIED ERGONOMICS}, author={Kelaher, D and Nay, T and Lawrence, B and Lamar, S and Sommerich, CM}, year={2001}, month={Feb}, pages={101–110} }
 @article{joines_sommerich_2001, title={Comparison of self-assessment and partnered-assessment as cost-effective alternative methods for office workstation evaluation}, volume={28}, ISSN={0169-8141}, url={http://dx.doi.org/10.1016/s0169-8141(01)00039-7}, DOI={10.1016/S0169-8141(01)00039-7}, abstractNote={A study was conducted in order to determine if anthropometric and office workstation measurements could be accurately collected individually by the employees who worked as those stations, or alternatively by two-person teams consisting of the employee and a co-worker. An iterative process was used to develop a method that would: (1) require a minimum number of measurements to be made by the employees, (2) produce an acceptable level of accuracy, and (3) provide useful information for analyzing employee–workstation fit. Results of the study showed acceptable accuracy when using a combined assisted and unassisted data collection approach. Office workstation assessment can be a challenge for companies with large numbers of employees working in office settings, particularly if those settings are distributed across a country or the globe. Developing a formulaic method for accurately measuring those workstations by someone other than the company's expert (ergonomist or other) has several benefits, including: (1) ability to measure more workstations in the same time period; (2) freeing the expert to perform tasks and analyses that require his/her expertise; and (3) inducing active involvement of employees in the company's health and safety (or ergonomics) efforts.}, number={6}, journal={International Journal of Industrial Ergonomics}, publisher={Elsevier BV}, author={Joines, Sharon M.B and Sommerich, Carolyn M}, year={2001}, month={Dec}, pages={327–340} }
 @article{sommerich_joines_psihogios_2001, title={Effects of Computer Monitor Viewing Angle and Related Factors on Strain, Performance, and Preference Outcomes}, volume={43}, ISSN={0018-7208 1547-8181}, url={http://dx.doi.org/10.1518/001872001775992480}, DOI={10.1518/001872001775992480}, abstractNote={ A model of visual and musculoskeletal strain associated with computer monitor placement was developed. The main premise of which is that monitor placement decisions must take into consideration development of both visual and musculoskeletal strains. Certain factors in the model that were thought to affect one or both types of strain, or that were considered important to rule out for effect, were tested in a lab setting. These factors were viewing angle (eye level, midlevel, low level), monitor size (14 in., 19 in.), keyboard familiarity (touch typist, nontouch typist), and task (reading, mousing, typing). Outcomes included indicators of visual and musculoskeletal strain, preference, and performance. Muscle activity was generally greater for the low viewing angle, for the standard monitor (14 in.), and for non-touch typists. Participants preferred the midlevel placement. Task performance was slightly diminished with eye-level placement. Results are interpreted in relation to the model and to several hypotheses that were formed to focus the inquiry. Actual or potential applications of this research include monitor placement decisions in the design or modification of computer workstations }, number={1}, journal={Human Factors: The Journal of the Human Factors and Ergonomics Society}, publisher={SAGE Publications}, author={Sommerich, Carolyn M. and Joines, Sharon M. B. and Psihogios, Jennie P.}, year={2001}, month={Mar}, pages={39–55} }
 @article{sommerich_joines_hermans_moon_2000, title={Use of surface electromyography to estimate neck muscle activity}, volume={10}, ISSN={1050-6411}, url={http://dx.doi.org/10.1016/s1050-6411(00)00033-x}, DOI={10.1016/S1050-6411(00)00033-X}, abstractNote={This paper reviews the literature concerning the use of surface electromyography (sEMG) for the study of the neck musculature in response to work and workplace design during light work and semi-static tasks. The paper also draws upon basic research and biomechanical modeling in order to provide methodological recommendations for the use of surface electromyography in this region of the body and to identify areas which require further investigation. The paper includes review and discussion of electrode site location, methods of normalization, data reliability, and factors that can affect sEMG signals from this region, including noise, physiologic artifact, stress, visual deficiencies, and pain. General guidance for maximum exertions with the neck musculature, for sEMG normalization or other purposes, is also included.}, number={6}, journal={Journal of Electromyography and Kinesiology}, publisher={Elsevier BV}, author={Sommerich, Carolyn M and Joines, Sharon M.B and Hermans, Veerle and Moon, Samuel D}, year={2000}, month={Dec}, pages={377–398} }
 @inbook{sommerich_1999, title={Economic analysis for ergonomics programs}, booktitle={The occupational ergonomics handbook: Ch. 83}, publisher={Boca Raton, CRC Press}, author={Sommerich, C. M.}, editor={W. Karwowski and Marras, W. S.Editors}, year={1999} }
 @inbook{sommerich_1999, title={Upper extermity supports}, booktitle={The industrial ergonomics handbook: Ch. 77}, publisher={Boca Raton, CRC Press}, author={Sommerich, C. M.}, editor={W. Karwowski and Marras, W. S.Editors}, year={1999} }
 @article{sommerich_marras_parnianpour_1998, title={A method for developing biomechanical profiles of hand-intensive tasks}, volume={13}, number={4-5}, journal={Clinical Biomechanics (Bristol, Avon)}, author={Sommerich, C. M. and Marras, W. S. and Parnianpour, M.}, year={1998}, pages={261–271} }
 @inbook{sommerich_mirka_1998, title={Managing work-related musculoskeletal injuries}, booktitle={Ergonomics in manufacturing: Raising productivity through workplace improvement (Ch. 19)}, publisher={Dearborn, Mich.: Society of Manufacturing Engineers; Norcross, Ga.: Engineering & Management Press}, author={Sommerich, C. M. and Mirka, G. A.}, editor={Karwowski, W. and Salvendy, G.Editors}, year={1998} }