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Psychosocial Aspects of VDU Work

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Computers provide efficiency, competitive advantages and the ability to carry out work processes that would not be possible without their use. Areas such as manufacturing process control, inventory management, records management, complex systems control and office automation have all benefited from automation. Computerization requires substantial infrastructure support in order to function properly. In addition to architectural and electrical changes needed to accommodate the machines themselves, the introduction of computerization requires changes in employee knowledge and skills, and application of new methods of managing work. The demands placed on jobs which use computers can be very different from those of traditional jobs. Often computerized jobs are more sedentary and may require more thinking and mental attention to tasks, while at the same time require less physical energy expenditure. Production demands can be high, with constant work pressure and little room for decision-making.

The economic advantages of computers at work have overshadowed associated potential health, safety and social problems for workers, such as job loss, cumulative trauma disorders and increased mental stress. The transition from more traditional forms of work to computerization has been difficult in many workplaces, and has resulted in significant psychosocial and sociotechnical problems for the workforce.

Psychosocial Problems Specific to VDUs

Research studies (for example, Bradley 1983 and 1989; Bikson 1987; Westlander 1989; Westlander and Aberg 1992; Johansson and Aronsson 1984; Stellman et al. 1987b; Smith et al. 1981 and 1992a) have documented how the introduction of computers into the workplace has brought substantial changes in the process of work, in social relationships, in management style and in the nature and content of job tasks. In the 1980s, the implementation of the technological changeover to computerization was most often a “top-down” process in which employees had no input into the decisions regarding the new technology or the new work structures. As a result, many industrial relations, physical and mental health problems arose.

Experts disagree on the success of changes that are occurring in offices, with some arguing that computer technology improves the quality of work and enhances productivity (Strassmann 1985), while others compare computers to earlier forms of technology, such as assembly-line production that also make working conditions worse and increase job stress (Moshowitz 1986; Zuboff 1988). We believe that visual display unit (VDU) technology does affect work in various ways, but technology is only one element of a larger work system that includes the individual, tasks, environment and organizational factors.

Conceptualizing Computerized Job Design

Many working conditions jointly influence the VDU user. The authors have proposed a comprehensive job design model which illustrates the various facets of working conditions which can interact and accumulate to produce stress (Smith and Carayon-Sainfort 1989). Figure 1 illustrates this conceptual model for the various elements of a work system that can exert loads on workers and may result in stress. At the centre of this model is the individual with his/her unique physical characteristics, perceptions, personality and behaviour. The individual uses technologies to perform specific job tasks. The nature of the technologies, to a large extent, determines performance and the skills and knowledge needed by the worker to use the technology effectively. The requirements of the task also affect the required skill and knowledge levels needed. Both the tasks and technologies affect the job content and the mental and physical demands. The model also shows that the tasks and technologies are placed within the context of a work setting that comprises the physical and the social environment. The overall environment itself can affect comfort, psychological moods and attitudes. Finally, the organizational structure of work defines the nature and level of individual involvement, worker interactions, and levels of control. Supervision and standards of performance are all affected by the nature of the organization.

Figure 1. Model of working conditions and their impact on the individual


This model helps to explain relationships between job requirements, psychological and physical loads and resulting health strains. It represents a systems concept in which any one element can influence any other element, and in which all elements interact to determine the way in which work is accomplished and the effectiveness of the work in achieving individual and organizational needs and goals. The application of the model to the VDU workplace is described below.




Physical environmental factors have been implicated as job stressors in the office and elsewhere. General air quality and housekeeping contribute, for example, to sick building syndrome and other stress responses (Stellman et al. 1985; Hedge, Erickson and Rubin 1992.) Noise is a well-known environmental stressor which can cause increases in arousal, blood pressure, and negative psychological mood (Cohen and Weinstein 1981). Environmental conditions that produce sensory disruption and make it more difficult to carry out tasks increase the level of worker stress and emotional irritation are other examples (Smith et al. 1981; Sauter et al. 1983b).


With the introduction of computer technology, expectations regarding performance increase. Additional pressure on workers is created because they are expected to perform at a higher level all the time. Excessive workload and work pressure are significant stressors for computer users (Smith et al. 1981; Piotrkowski, Cohen and Coray 1992; Sainfort 1990). New types of work demands are appearing with the increasing use of computers. For instance, cognitive demands are likely to be sources of increased stress for VDU users (Frese 1987). These are all facets of job demands.

Electronic Monitoring of Employee Performance

The use of electronic methods to monitor employee work performance has increased substantially with the widespread use of personal computers which make such monitoring quick and easy. Monitoring provides information which can be used by employers to better manage technological and human resources. With electronic monitoring it is possible to pinpoint bottlenecks, production delays and below average (or below standard) performance of employees in real time. New electronic communication technologies have the capability of tracking the performance of individual elements of a communication system and of pinpointing individual worker inputs. Such work elements as data entry into computer terminals, telephone conversations, and electronic mail messages can all be examined through the use of electronic surveillance.

Electronic monitoring increases management control over the workforce, and may lead to organisational management approaches that are stressful. This raises important issues about the accuracy of the monitoring system and how well it represents worker contributions to the employer’s success, the invasion of worker privacy, worker versus technology control over job tasks, and the implications of management styles that use monitored information to direct worker behaviour on the job (Smith and Amick 1989; Amick and Smith 1992; Carayon 1993b). Monitoring can bring about increased production, but it may also produce job stress, absences from work, turnover in the workforce and sabotage. When electronic monitoring is combined with incentive systems for increased production, work-related stress can also be increased (OTA 1987; Smith et al. 1992a). In addition, such electronic performance monitoring raises issues of worker privacy (ILO 1991) and several countries have banned the use of individual performance monitoring.

A basic requirement of electronic monitoring is that work tasks be broken up into activities that can easily be quantified and measured, which usually results in a job design approach that reduces the content of the tasks by removing complexity and thinking, which are replaced by repetitive action. The underlying philosophy is similar to a basic principle of “Scientific Management” (Taylor 1911) that calls for work “simplification.”

In one company, for example, a telephone monitoring capability was included with a new telephone system for customer service operators. The monitoring system distributed incoming telephone calls from customers, timed the calls and allowed for supervisor eavesdropping on employee telephone conversations. This system was instituted under the guise of a work flow scheduling tool for determining the peak periods for telephone calls to determine when extra operators would be needed. Instead of using the monitoring system solely for that purpose, management also used the data to establish work performance standards, (seconds per transaction) and to bring disciplinary action against employees with “below average performance.” This electronic monitoring system introduced a pressure to perform above average because of fear of reprimand. Research has shown that such work pressure is not conducive to good performance but rather can bring about adverse health consequences (Cooper and Marshall 1976; Smith 1987). In fact, the monitoring system described was found to have increased employee stress and lowered the quality of production (Smith et al. 1992a).

Electronic monitoring can influence worker self-image and feelings of self-worth. In some cases, monitoring could enhance feelings of self-worth if the worker gets positive feedback. The fact that management has taken an interest in the worker as a valuable resource is another possible positive outcome. However, both effects may be perceived differently by workers, particularly if poor performance leads to punishment or reprimand. Fear of negative evaluation can produce anxiety and may damage self-esteem and self-image. Indeed electronic monitoring can create known adverse working conditions, such as paced work, lack of worker involvement, reduced task variety and task clarity, reduced peer social support, reduced supervisory support, fear of job loss, or routine work activities, and lack of control over tasks (Amick and Smith 1992; Carayon 1993).

Michael J. Smith

Positive aspects also exist since computers are able to do many of the simple, repetitive tasks that were previously done manually, which can reduce the repetitiveness of the job, increase the content of the job and make it more meaningful. This is not universally true, however, since many new computer jobs, such as data entry, are still repetitive and boring. Computers can also provide performance feedback that is not available with other technologies (Kalimo and Leppanen 1985), which can reduce ambiguity.

Some aspects of computerized work have been linked to decreased control, which has been identified as a major source of stress for clerical computer users. Uncertainty regarding the duration of computer-related problems, such as breakdown and slowdown, can be a source of stress (Johansson and Aronsson 1984; Carayon-Sainfort 1992). Computer-related problems can be particularly stressful if workers, such as airline reservation clerks, are highly dependent on the technology to perform their job.


The technology being used by the worker often defines his or her ability to accomplish tasks and the extent of physiological and psychological load. If the technology produces either too much or too little workload, increased stress and adverse physical health outcomes can occur (Smith et al. 1981; Johansson and Aronsson 1984; Ostberg and Nilsson 1985). Technology is changing at a rapid pace, forcing workers to adjust their skills and knowledge continuously to keep up. In addition, today’s skills can quickly become obsolete. Technological obsolescence may be due to job de-skilling and impoverished job content or to inadequate skills and training. Workers who do not have the time or resources to keep up with the technology may feel threatened by the technology and may worry about losing their job. Thus, workers’ fears of having inadequate skills to use the new technology are one of the main adverse influences of technology, which training, of course, can help to offset. Another effect of the introduction of technology is the fear of job loss due to increased efficiency of technology (Ostberg and Nilsson 1985; Smith, Carayon and Miezio 1987).

Intensive, repetitive, long sessions at the VDU can also contribute to increased ergonomic stress and strain (Stammerjohn, Smith and Cohen 1981; Sauter et al. 1983b; Smith et al. 1992b) and can create visual or musculoskeletal discomfort and disorders, as described elsewhere in the chapter.

Organizational factors

The organizational context of work can influence worker stress and health. When technology requires new skills, the way in which workers are introduced to the new technology and the organizational support they receive, such as appropriate training and time to acclimatize, has been related to the levels of stress and emotional disturbances experienced (Smith, Carayon and Miezio 1987). The opportunity for growth and promotion in a job (career development) is also related to stress (Smith et al. 1981). Job future uncertainty is a major source of stress for computer users (Sauter et al. 1983b; Carayon 1993a) and the possibility of job loss also creates stress (Smith et al. 1981; Kasl 1978).

Work scheduling, such as shift work and overtime, have been shown to have negative mental and physical health consequences (Monk and Tepas 1985; Breslow and Buell 1960). Shift work is increasingly used by companies that want or need to keep computers running continuously. Overtime is often needed to ensure that workers keep up with the workload, especially when work remains incomplete as a result of delays due to computer breakdown or misfunction.

Computers provide management with the capability to continuously monitor employee performance electronically, which has the potential to create stressful working conditions, such as by increasing work pressure (see the box “Electronic Monitoring”). Negative employee-supervisor relationships and feelings of lack of control can increase in electronically supervised workplaces.

The introduction of VDU technology has affected social relationships at work. Social isolation has been identified as a major source of stress for computer users (Lindström 1991; Yang and Carayon 1993) since the increased time spent working on computers reduces the time that workers have to socialize and receive or give social support. The need for supportive supervisors and co-workers has been well documented (House 1981). Social support can moderate the impact of other stressors on worker stress. Thus, support from colleagues, supervisor or computer staff becomes important for the worker who is experiencing computer-related problems but the computer work environment may, ironically, reduce the level of such social support available.

The individual

A number of personal factors such as personality, physical health status, skills and abilities, physical conditioning, prior experiences and learning, motives, goals and needs determine the physical and psychological effects just described (Levi 1972).

Improving the Psychosocial Characteristics of VDU Work

The first step in making VDU work less stressful is to identify work organization and job design features that can promote psychosocial problems so that they can be modified, always bearing in mind that VDU problems which can lead to job stress are seldom the result of single aspects of the organization or of job design, but rather, are a combination of many aspects of improper work design. Thus, solutions for reducing or eliminating job stress must be comprehensive and deal with many improper work design factors simultaneously. Solutions that focus on only one or two factors will not succeed. (See figure 2.)

Figure 2. Keys to reducing isolation and stress


Improvements in job design should start with the work organization providing a supportive environment for employees. Such an environment enhances employee motivation to work and feelings of security, and it reduces feelings of stress (House 1981). A policy statement that defines the importance of employees within an organization and is explicit on how the organization will provide a supportive environment is a good first step. One very effective means for providing support to employees is to provide supervisors and managers with specific training in methods for being supportive. Supportive supervisors can serve as buffers that “protect” employees from unnecessary organizational or technological stresses.


The content of job tasks has long been recognized as important for employee motivation and productivity (Herzberg 1974; Hackman and Oldham 1976). More recently the relationship between job content and job stress reactions has been elucidated (Cooper and Marshall 1976; Smith 1987). Three main aspects of job content that are of specific relevance to VDU work are task complexity, employee skills and career opportunities. In some respects, these are all related to the concept of developing the motivational climate for employee job satisfaction and psychological growth, which deals with the improvement of employees’ intellectual capabilities and skills, increased ego enhancement or self-image and increased social group recognition of individual achievement.

The primary means for enhancing job content is to increase the skill level for performing job tasks, which typically means enlarging the scope of job tasks, as well as enriching the elements of each specific task (Herzberg 1974). Enlarging the number of tasks increases the repertoire of skills needed for successful task performance, and also increases the number of employee decisions made while defining task sequences and activities. An increase in the skill level of the job content promotes employee self-image of personal worth and of value to the organization. It also enhances the positive image of the individual in his or her social work group within the organization.

Increasing the complexity of the tasks, which means increasing the amount of thinking and decision-making involved, is a logical next step that can be achieved by combining simple tasks into sets of related activities that have to be coordinated, or by adding mental tasks that require additional knowledge and computational skills. Specifically, when computerized technology is introduced, new tasks in general will have requirements that exceed the current knowledge and skills of the employees who are to perform them. Thus there is a need to train employees in the new aspects of the tasks so that they will have the skills to perform the tasks adequately. Such training has more than one benefit, since it not only may improve employee knowledge and skills, and thus enhance performance, but may also enhance employee self-esteem and confidence. Providing training also shows the employee that the employer is willing to invest in his or her skill enhancement, and thus promotes confidence in employment stability and job future.

The amount of control that an employee has over the job has a powerful psychosocial influence (Karasek et al. 1981; Sauter, Cooper and Hurrell 1989). Important aspects of control can be defined by the answers to the questions, “What, how and when?” The nature of the tasks to be undertaken, the need for coordination among employees, the methods to be used to carry out the tasks and the scheduling of the tasks can all be defined by answers to these questions. Control can be designed into jobs at the levels of the task, the work unit and the organization (Sainfort 1991; Gardell 1971). At the task level, the employee can be given autonomy in the methods and procedures used in completing the task.

At the work-unit level, groups of employees can self-manage several interrelated tasks and the group itself can decide on who will perform particular tasks, the scheduling of tasks, coordination of tasks and production standards to meet organizational goals. At the organization level, employees can participate in structured activities that provide input to management about employee opinions or quality improvement suggestions. When the levels of control available are limited, it is better to introduce autonomy at the task level and then work up the organizational structure, insofar as possible (Gardell 1971).

One natural result of computer automation appears to be an increased workload, since the purpose of the automation is to enhance the quantity and quality of work output. Many organizations believe that such an increase is necessary in order to pay for the investment in the automation. However, establishing the appropriate workload is problematic. Scientific methods have been developed by industrial engineers for determining appropriate work methods and workloads (the performance requirements of jobs). Such methods have been used successfully in manufacturing industries for decades, but have had little application in office settings, even after office computerization. The use of scientific means, such as those described by Kanawaty (1979) and Salvendy (1992), to establish workloads for VDU operators, should be a high priority for every organization, since such methods set reasonable production standards or work output requirements, help to protect employees from excessive workloads, as well as help to ensure the quality of products.

The demand that is associated with the high levels of concentration required for computerized tasks can diminish the amount of social interaction during work, leading to social isolation of employees. To counter this effect, opportunities for socialization for employees not engaged in computerized tasks, and for employees who are on rest breaks, should be provided. Non-computerized tasks which do not require extensive concentration could be organized in such a way that employees can work in close proximity to one another and thus have the opportunity to talk among themselves. Such socialization provides social support, which is known to be an essential modifying factor in reducing adverse mental health effects and physical disorders such as cardiovascular diseases (House 1981). Socialization naturally also reduces social isolation and thus promotes improved mental health.

Since poor ergonomic conditions can also lead to psychosocial problems for VDU users, proper ergonomic conditions are an essential element of complete job design. This is covered in some detail in other articles in this chapter and elsewhere in the Encyclopaedia.

Finding Balance

Since there are no “perfect” jobs or “perfect” workplaces free from all psychosocial and ergonomic stressors, we must often compromise when making improvements at the workplace. Redesigning processes generally involves “trade-offs” between excellent working conditions and the need to have acceptable productivity. This requires us to think about how to achieve the best “balance” between positive benefits for employee health and productivity. Unfortunately, since so many factors can produce adverse psychosocial conditions that lead to stress, and since these factors are interrelated, modifications in one factor may not be beneficial if concomitant changes are not made in other related factors. In general, two aspects of balance should be addressed: the balance of the total system and compensatory balance.

System balance is based on the idea that a workplace or process or job is more than the sum of the individual components of the system. The interplay among the various components produces results that are greater (or less) than the sum of the individual parts and determines the potential for the system to produce positive results. Thus, job improvements must take account of and accommodate the entire work system. If an organization concentrates solely on the technological component of the system, there will be an imbalance because personal and psychosocial factors will have been neglected. The model given in figure 1 of the work system can be used to identify and understand the relationships between job demands, job design factors, and stress which must be balanced.

Since it is seldom possible to eliminate all psychosocial factors that cause stress, either because of financial considerations, or because it is impossible to change inherent aspects of job tasks, compensatory balance techniques are employed. Compensatory balance seeks to reduce psychological stress by changing aspects of work that can be altered in a positive direction to compensate for those aspects that cannot be changed. Five elements of the work system—physical loads, work cycles, job content, control, and socialization—function in concert to provide the resources for achieving individual and organizational goals through compensatory balance. While we have described some of the potential negative attributes of these elements in terms of job stress, each also has positive aspects that can counteract the negative influences. For instance, inadequate skill to use new technology can be offset by employee training. Low job content that creates repetition and boredom can be balanced by an organizational supervisory structure that promotes employee involvement and control over tasks, and job enlargement that introduces task variety. The social conditions of VDU work could be improved by balancing the loads that are potentially stressful and by considering all of the work elements and their potential for promoting or reducing stress. The organizational structure itself could be adapted to accommodate enriched jobs in order to provide support to the individual. Increased staffing levels, increasing the levels of shared responsibilities or increasing the financial resources put toward worker well-being are other possible solutions.



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