A multidisciplinary approach to solving computer related vision problems

Ophthalmic & Physiological Optics ISSN 0275-5408

REVIEW

A multidisciplinary approach to solving computer related vision problems Jennifer Long1 and Magne Helland2 1

School of Optometry and Vision Science, University of New South Wales, Sydney, Australia, and 2Department of Optometry and Visual Science, Buskerud University College, Kongsberg, Norway

Citation information: Long J & Helland M. A multidisciplinary approach to solving computer related vision problems. Ophthalmic Physiol Opt 2012, 32, 429–435. doi: 10.1111/j.1475-1313.2012.00911.x

Keywords: control rooms, ergonomics, multidisciplinary teams, optometry, visual displays Correspondence: Jennifer Long E-mail address: [email protected] Received: 4 January 2012; Accepted: 16 March 2012

Abstract Purpose: This paper proposes a multidisciplinary approach to solving computer related vision issues by including optometry as a part of the problem-solving team. Recent findings: Computer workstation design is increasing in complexity. There are at least ten different professions who contribute to workstation design or who provide advice to improve worker comfort, safety and efficiency. Optometrists have a role identifying and solving computer-related vision issues and in prescribing appropriate optical devices. However, it is possible that advice given by optometrists to improve visual comfort may conflict with other requirements and demands within the workplace. A multidisciplinary approach has been advocated for solving computer related vision issues. There are opportunities for optometrists to collaborate with ergonomists, who coordinate information from physical, cognitive and organisational disciplines to enact holistic solutions to problems. This paper proposes a model of collaboration and examples of successful partnerships at a number of professional levels including individual relationships between optometrists and ergonomists when they have mutual clients/patients, in undergraduate and postgraduate education and in research. There is also scope for dialogue between optometry and ergonomics professional associations. Summary: A multidisciplinary approach offers the opportunity to solve vision related computer issues in a cohesive, rather than fragmented way. Further exploration is required to understand the barriers to these professional relationships.

Information and communication technology (ICT) is a part of modern life for people of all ages. Although white collar work dominates in developed countries (e.g. 59% Australian workers in 2006,1 60% American workers in 20022) electronic displays are not confined to these industries, e.g. computers and visual displays are used in vehicles, hand held devices (including phones) and in industrial control rooms. Workers may also use multiple devices mounted at different working distances and displaying various computer applications. Figure 1 shows a typical industrial control room with nine desk mounted monitors, two of which are stacked vertically and five monitors suspended from the ceiling above head height.

Such complexity poses a challenge for the clinical optometrist who needs to be able to identify and solve visual issues associated with computer use3 and prescribe spectacle lenses according to the task requirements.4,5 An ageing population worldwide6 also means that optometrists need to consider the impact of presbyopia and vision complications of ocular and systemic disease on the ability of individuals to see and use ICT comfortably. For many presbyopic workers, ordinary general purpose spectacles are insufficient for comfortable ICT use.7–9 Ideally, optical appliances should be prescribed after the working environment has been configured8, and patients may ask optometrists for advice on this matter

Ophthalmic & Physiological Optics 32 (2012) 429–435 ª 2012 The College of Optometrists

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A multidisciplinary approach to solving vision ICT problems

J Long and M Helland

Figure 1. A typical industrial control room.

during clinical consultations.10,11 Unfortunately, it is not always a simple matter for an optometrist to advise their patient to alter their working distance (since the display may be fixed to the workstation), change the display magnification, colour or font size (if the application does not have this facility) or take more frequent rest breaks (if this does not fit in with shift arrangements or work demands). Recommendations to improve visual comfort can also have other ramifications in the workplace. For example, if the font size is increased on a display then less

information may be displayed on the screen page at any one time; this in turn could reduce productivity and increase the risk of musculoskeletal discomfort from mouse scrolling.12 Many different professions are involved in the design, manufacture and installation of computer workstations and ensuring that workers can perform their work comfortably, safely and efficiently (see Table 1). With such diverse input into the problem solving process, there is the risk that solutions to vision problems will become fragmented as each profession manages the issue according to their understanding of the problem.13 Cohesive and well-rounded solutions to vision related issues associated with computer use can be achieved by adopting a multidisciplinary approach.13–15 A multidisciplinary team is a group of individuals with various backgrounds and expertise who work together under one organisational umbrella or as a unique team to solve a problem.16 Ergonomics (also known as human factors) is a discipline which can achieve this aim since it has a broad scope which includes physical (e.g. workstation arrangement), cognitive (e.g. visual perception) and organisational factors (e.g. work design).17 Table 1 maps potential vision issues associated with visual comfort in the control room depicted in Figure 1 against these three domains.

Table 1. Visual issues associated with control rooms and complex multi-screen environments and the professions who may provide advice on this issue Domain of ergonomics/ human factors Physical

Cognitive

Visual issue within control room

Professions

Individual workers have adequate visual skills Visual corrections are appropriate for the task Display characteristics e.g. font size, display colours Ambient temperature and humidity and its effect on ocular comfort Location of computer monitors e.g. height, distance, arrangement at workstation Lighting (artificial and natural) and the ability of workers to adapt to illumination and luminance levels Air quality, chemical and microbial hazards and the effect on ocular surface health Amount of information displayed on each computer monitor

Optometry Optometry Engineering, interface design, optometry Occupational hygiene, occupational medicine, optometry

Colour coding within displays

Organisational

Workload and issues of divided attention Noise, alarms and other auditory distractions which compete with visual attention Workload and issues of divided attention Rest breaks and fatigue Shift length

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Architecture, ergonomics/human factors, engineering, optometry Architecture, engineering, lighting design, optometry Occupational hygiene, occupational medicine, optometry Engineering, ergonomics/human factors, interface design, psychology Engineering, ergonomics/human factors, interface design, optometry, psychology Ergonomics/human factors, management, psychology Ergonomics/human factors, psychology Ergonomics/human factors, management, psychology Ergonomics/human factors, management, occupational medicine, optometry, psychology Ergonomics/human factors, management, psychology




Table 2. An example of the process for designing and installing new visual displays in a workplace and the professions who may provide advice on this issue Stage

Description

Profession

Initiator 1

The need for a new visual displays is identified Task/job is analysed and workers are consulted to determine specifications which are required Computer software and hardware is sourced or designed based on the requirements identified in stage 1. Software options include custom designed software, off the shelf software which is used unmodified and off-the-shelf software which is customised for the workplace Work environment is designed taking into consideration industry standards, work and computer system requirements identified in stages 1 and 2 and commercial availability of products (hardware, infrastructure, furniture). Design aspects include: Number and location of displays Lighting, thermal and acoustic environment Post-occupancy modifications may be implemented. For example, relatively minor modifications to the location of displays, furniture and lighting. The requirements of individual workers are addressed, if indicated. For example: Task specific spectacles are prescribed Ancillary equipment is provided e.g., footrests

Management, workers Ergonomics/human factors, engineering, management, workers Management, interface design, engineering, ergonomics/human factors, optometry

2

3

4 5

Ergonomists strive to improve comfort, safety and productivity by ensuring a balance between the capabilities of individuals and the elements of the environment in which they interact. They achieve this by coordinating information gained from a variety of sources with the aim of enacting holistic solutions to problems.12 Optometry can contribute to this process by establishing professional partnerships with ergonomists. This is similar to shared care arrangements which optometrists may have with other healthcare professionals for patients with complex medical needs.18,19 There are many different levels at which optometrists and ergonomists can interact in the design and installation of ICT environments (see Table 2). Optometrists commonly participate in the last stage of this process (prescribing task appropriate eyewear) but may have involvement in stage 2 (e.g. providing advice on font colour or size), stage 3 (e.g. predicting vision issues within a work environment so these issues can be ‘‘designed out’’) or stage 4 (e.g. suggesting modifications to a lighting installation to solve glare related issues). This paper proposes a model of collaboration and examples of successful partnerships between optometry and ergonomics at a number of professional levels. In the workplace In an ideal world, optometrists participating with ergonomists in multidisciplinary teams would visit workplaces to observe the environment firsthand. This would help optometrists understand the work context and any competing issues (e.g. if displays are fixed to the workstation)

Architecture, engineering, ergonomics/human factors, lighting design, optometry

Architecture, engineering, ergonomics/human factors, lighting design, optometry Ergonomics/human factors, optometry

and assist them in providing solutions which can actually be implemented. There are optometrists who work in this way, but there are very few reports in the scientific literature documenting these relationships. One example which has been extensively reported is a Scandinavian project conducted over more than 15 years which has included optometrists, occupational physicians, lighting designers, workstation designers and occupational health personnel.20–22 The investigation has included evaluation of visual discomfort with lighting conditions, musculoskeletal discomfort and the effect of spectacle corrections on visual comfort.20 It was later expanded to evaluate musculoskeletal, visual and psychosocial stress in office workers associated with moving from single occupancy to open plan offices.21,22 Initial optometric involvement was to provide eye examinations, prescribe spectacles and gather ocular-specific data (e.g. measurements of eye-blink rate). However, during the open-plan office stage of the project the optometrists on the team identified glare issues with the lighting and were able to negotiate with the lighting designers for an alternative installation to avoid glare problems.21 Modifications to the lighting included replacing the reflectors within the luminaires from shiny to semi-diffuse (to reduce the luminance from the reflector-louvre system), lowering the height of the fittings from 2.8 m to 2.15 m (to minimise the direct view of the fluorescent lamps within the luminaires) and installing Venetian blinds on the windows (to provide better control of natural light). This process was facilitated by the workplace medical doctor who had training in occupational medicine and coordinated the project.


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This was essentially a research project. One of the optometrist participants had worked with the company health care team for many years while the other was invited to participate through his academic institution. This should not preclude optometrists in clinical practice from participating in similar arrangements. When relationships are built with industry in other capacities (e.g. through the provision of prescription eyewear for computer users) opportunities for further collaboration will arise as relationships develop. In the consultation room Building relationships with industry sounds easy – but is it? One way to build associations between ergonomics and optometry is to acknowledge that optometrists and ergonomists may already have mutual clients/ patients. Rather than relying on the patient, formal communication between the two professions can help optometrists provide more targeted solutions and improve vision related outcomes associated with ICT use. For example: (1) Ergonomists can provide information about the task requirements to optometrists e.g. by photographs of the work environment and measurements of working distances and viewing positions23–25. This will assist optometrists in understanding the work environment before they make prescribing decisions. Table 3 provides an example of the type of information which could be provided by an ergonomist prior to spectacles being prescribed for a worker who works in the control room shown in Figure 1. (2) Optometrists can communicate their findings and prescribing decisions to ergonomists. It would be difficult to prescribe spectacles for a presbyope who works at the

control room shown in Figure 1: single vision and extended focus lenses (i.e., specially designed spectacle lenses for computer work primarily focussed for intermediate and near distances) would be suitable for viewing the vertically stacked monitors but would not allow clear distance viewing, whereas progressive lenses would allow clear viewing both at distance as well as the monitors suspended from the ceiling but would require neck flexion when viewing the vertically stacked monitors. A model for this type of collaboration is described by the Norwegian Labour Inspection Authority and has three stages: (1) an ergonomics assessment is conducted within the workplace and the workstation environment is optimised. (2) The lighting conditions are evaluated and optimised. (3) Visual parameters are measured e.g. viewing distance, viewing angles and gaze direction.26 This process has been successfully used by the first author (JL) in a control room environment. In this case, the first two stages were conducted by ergonomists and engineers hired by the employer. The third stage consisted of the first author making physical measurements of the work environment and evaluating commercially available spectacle lens options to determine which lens designs would be most appropriate. Information about the work environment and potentially suitable (and unsuitable) spectacle lens designs were included in a letter provided to the optometrist by the control room operators. This assisted the prescribing of appropriate eyewear and initiated dialogue between the ergonomists and optometrists. Ergonomists in Australia have indicated that they would like to have working relationships with clinical optometrists but report difficulty identifying optometrists interested in these collaborations. Communication could be initiated by shared professional development events

Table 3. Task requirements information which could be provided by an ergonomist prior to an optometrist prescribing spectacles for a worker who works in the control room shown in Figure 1. Please provide a diagram or a photograph of the worker sitting/standing at their workstation. Either indicate on the diagram or write below the following dimensions and measurements: Number of displays How many displays does this worker use? What proportion of time is spent using each display? Location of displays What is the height of each display relative to the worker’s eyes? What is the viewing distance to each display? What is the horizontal location of the display relative to the worker’s eyes? For example: If using 2 monitors, is the worker seated midway between the two? Do they swivel or move their chair to view each display? Size of displays What is the size of each visual display? (i.e. monitor size) What is the total width of the display (i.e. all the monitors combined, physical size in centimetres)? What size font does the worker typically view (physical size in millimetres)? Other task requirements Are any other tasks performed e.g. reading, walking around or viewing out of the window? Is it acceptable for the worker to have more than one pair of spectacles e.g. one for distance viewing and one which is task-specific? Are tinted lenses (e.g. photochromic lenses) required? Do task-specific spectacles need to be constructed as prescription safety spectacles (e.g. provide impact resistance)?

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between the professions.23 This strategy is currently being trialled with the Human Factors and Ergonomics Society of Australia (HFESA) and the Optometrists Association of Australia (OAA) so that individual optometrists and ergonomists can meet each other, participate in a shared professional development event, learn from each other and strengthen communication when they have mutual clients. A more informal approach is to invite optometrists to ergonomics conferences, and vice versa, when there is relevant visual ergonomics content so that optometrists and ergonomists can create their own networks. This is being explored this year in Scandinavia by advertising the Nordic Ergonomics Society conference (which has a strong visual ergonomics component) in optometric publications. Overcoming the barriers One of the challenges for inter-professional partnerships is that individual team members have different perspectives of issues and problems13 and this can be perceived as a hindrance to the problem solving process.27 It has been argued that multidisciplinary teams will only be effective if the participants have education and training in the environment in which they are working.27 While this may be a valid suggestion for an ergonomist working full-time in an engineering or manufacturing firm27 and for optometrists who participate in on-site workplace interventions, it may not be feasible or practical for professionals who provide specific expertise in a more limited capacity, e.g. clinical optometrists prescribing eyewear for computer users. Irrespective of whether optometrists deal with vision and ICT issues by visiting workplaces or remaining in their consultation room, it is important that they have a global understanding of the work environment, are aware of the scope of work of the other team members and are prepared to negotiate solutions to problems.28 An understanding of ergonomics and prescribing appropriate optical appliances for occupational use is a core competency for optometrists in some countries.10,11,24 Expanding this to include discussion about optometric involvement in multidisciplinary teams can improve the success of these relationships. This strategy has also been proposed for occupational medicine.29 It is worth remembering that inter-disciplinary collaborations develop over time and rely on an understanding of the potential contribution which can be made by other professions. For example, control room design has long been the province of engineering and it has only been relatively recently that ergonomics has participated in the design process.30 Now it is accepted practice that architects, engineers, system designers, ergonomists and user


representatives may be involved in the design and installation of full-scale simulations of control rooms before final construction.31 Visual issues are acknowledged in control room environments31,32 but optometrists are rarely included in these teams. One reason for this could be lack of awareness of their potential contribution. The first author (JL) was recently invited by the ergonomics team at an industrial site to give a presentation to engineers about visual issues and control rooms. This presentation was part of a larger education program within the organisation to introduce engineers to different aspects of ergonomics and design. In the ensuing discussion, one engineer commented that he was aware of the various rules for interface design and monitor placement but did not understand the rationale for these rules. He believed that if he was provided with specific information about visual capabilities and the limitations of spectacle lens for presbyopia then it would be relatively easy to incorporate these considerations into future designs, e.g. by designing the work environment for a lesser number of viewing distances33 or limiting the use of vertically stacked monitors. Ergonomists are often responsible for disseminating information about vision and work within workplaces and promoting the use of task-specific eyewear. There are many existing health and safety publications34,35 which assist these professionals with this process. However, there is a need for optometric involvement in undergraduate and postgraduate health and safety programs as this will raise the profile and increase general understanding of vision issues within workplaces. For several years the first author (JL) has participated in this type of teaching. Anecdotal reports from course participants indicate that this is beneficial for their work and improves confidence when dealing with eye care practitioners. Future directions The control room in Figure 1 is typical of a modern control room. As technological capabilities improve it is likely that these work environments will increase in complexity through the installation of more monitors, the use of virtual displays and the invention of other types of ICT interfaces. Existing spectacle lens designs for presbyopia are often unsuitable for modern computer workstations. This can be a frustrating issue for optometrists who try to prescribe appropriate eyewear, for users who find the eyewear uncomfortable and for health and safety personnel who manage problems arising from poor posture or the inability of workers to see clearly. The advent of new forms of technology opens up possibilities for partnerships between interface designers and vision scientists to devise alternative display options (as


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opposed to the current trend of providing more and larger monitors at individual workstations). There is also the potential for partnerships between workstation designers and spectacle lens manufacturers to design alternative spectacle lenses for presbyopia which meet the visual requirements of these modern work environments. Research is required into the acceptance of task specific lenses for modern computer environments by optometrists, industry and patients while addressing any barriers to their use. This will supplement earlier research published when task specific lenses were first introduced into the ophthalmic market.36,37 The optometric profession has a history of contributing to knowledge and understanding about vision and computers in the development of guidelines, standards and recommendations.38,39 This needs to continue, particularly for the use of new technology, complex multi-screen workstations and mobile (flexible) workstation arrangements. There is also scope for dialogue between optometry and ergonomics at a professional level, both nationally (e.g. with ergonomics associations in individual countries) and internationally (e.g. with the International Ergonomics Association Technical Committee for Visual Ergonomics). Further exploration is required to understand the barriers to these collaborative relationships (including funding arrangements for optometric participation), how best to evaluate and document the short- and long-term effectiveness of these partnerships and how to encourage publication of case examples which illustrate successful working partnerships. Conclusion There are many opportunities for developing partnerships between optometry and ergonomics. A multidisciplinary approach which includes optometrists offers the opportunity to solve vision related computer issues in a cohesive manner. This has the potential to improve visual comfort whether in complex visual environments (as illustrated in this paper), at standard office computers or when using technology for personal and leisure activities. References 1. Australian Bureau of Statistics (ABS). 2006 Census of Population and Housing: industry of Employment by Occupation Cat. No 2068.0-2006, 2006. 2. Department for Professional Employees. Current Statistics On White Collar Employees. Department for Professional Employees: Washington DC, 2003. 3. Rosenfield M. Computer vision syndrome: a review of ocular causes and potential treatments. Ophthal Physiol Optics 2011; 31: 502–515.

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