37th Annual Conference Ergonomics Society of Australia Inc. KEYNOTE PAPERS 1 Better Integration 27-30 November 2001 2 37th Annual Conference Ergonomics Society of Australia Inc. Learning from Experts: How the Study of Expertise Might Help Design More Effective Training Bruce Abernethy School of Human Movement Studies, The University of Queensland Keywords: Expertise, Skill Acquisition, Practice, Learning, Ergonomics ABSTRACT There is now a significant body of literature, drawn from a diverse range of cognitive, occupational and sporting tasks, that identifies factors that discriminate expert from lesser skilled performers and that demonstrates systematic differences in the task information picked up and used by people of different skill levels. This paper provides a brief overview of what the existing expertise literature has revealed with respect to limiting factors to skilled performance, with respect to skill-related differences in information usage, and with respect to how learning to be an expert takes place. Specific implications are drawn as to how knowledge about the distinguishing attributes of expert performance might be used, in a targeted way, to develop training programs to accelerate the acquisition of expertise, to improve workplace and task designs, and to facilitate expert systems development. 1. EXPERTISE AND ERGONOMICS Expertise is highly sought and valued in the workplace, just as it is in a wide range of other settings. Expertise is not easily acquired; indeed in most domains in which expertise has been systematically studied the attainment of expert performance is typically only seen after at least 10 years, 10,000 hours, or literally millions of trials of daily, effortful practice (Ericsson et al., 1993). Consequently, finding means of facilitating the rate of acquisition of expertise is particularly desirable. The scholarly study of expertise is concerned with describing and understanding the nature of the control processes that fundamentally differentiate the expert performer from the lesser skilled and the processes through which expertise is acquired. Because of the time scales involved, studying experts in natural tasks, like work tasks, provides a window into learning and skill optimisation that conventional, laboratory-based learning studies of untrained participants simply cannot replicate. However, despite concerted research efforts particularly over the past three decades, and the development of a solid descriptive base of expert performance characteristics, the underlying basis of expert performance and its acquisition remains quite poorly understood. An important focus for ergonomics is discovering superior training procedures, task designs or systems that can enhance productivity, efficiency and/or safety in the work setting. Such discovery is dependent upon the integration of information and approaches from a number of disciplines and otherwise discrete bodies of knowledge. The principal purpose of this paper is 3 Better Integration 27-30 November 2001 to highlight, by way of example, some of the important contributions the expanding body of knowledge on expertise can potentially make to contemporary ergonomics practice. There are a number of ways in which the study of expertise has the potential to provide benefits within the field of ergonomics. First, the comparison of the perceptual-motor skill and skill components of experts and novices in specific tasks can help identify the limiting factors to performance in the task of interest. Knowing those factors that do, and equally importantly do not, discriminate expert and novice performers can provide a principled basis for guiding emphasis within a practice/training schedule aimed at improving skill. Second, comparison of the information sources utilised by experts and novices can help determine what specific information must be learned in order to become an expert on a given task. Such knowledge has the potential to provide direct implications for the structure of instruction and the provision of feedback. Third, studying the life histories and practice experiences of experts can aid identification of factors critical to becoming an expert. Isolating these factors also has the potential to provide information of both theoretical and practical significance regarding skill learning (Abernethy, in press). Understanding gained about the limiting factors to task performance, about the distinguishing patterns of information usage by experts, and about factors necessary but not sufficient for the attainment of expertise can be potentially help not only in the design of training but also in the design of superior workspaces and task configurations (e.g., Noyes et al., 1996) and, through cognitive emulation (Slatter, 1987), in the development of expert systems. [Expert systems are artificially intelligent computer programs that use a body of knowledge to substitute for human operators in the performance of difficult or dangerous tasks (Hoc et al., 1995; Leibowitz, 1990).] Examples also exist of how identification and understanding of discrete stages in the transition from novice to expert can be used to directly guide decisions about career structuring and continuing education in professional workgroups such as nurses (Benner, 1984; Dreyfus & Dreyfus, 1986). Reciprocally, research in the workplace has much to potentially offer those interested in enhancing generic understanding of expertise. Given the experience that workers accrue over the duration of a career, the study of workplace skills offers researchers access to experts with levels of practice that may be greater than those found amongst performers in some of the other domains (chess, music and sport in particular) that have, to date, attracted substantially more research attention. It is germane, in this context, to recognise that some of the more influential, early studies on practice and learning (e.g., Bryan & Harter, 1899; Crossman, 1964) indeed came from the study of workplace skills. 2. ELEMENTS OF EXPERTISE The remainder of this paper provides a brief overview of what is known currently about expert-novice differences in some of the key processes underpinning the production of skilled actions of the type needed in the workplace. The overview is organised in terms of the major processing components of sensation, perception, cognition, action, attention and feedback, typically represented in traditional information-processing/stage models of human performance (e.g., Kantowitz, 1989; Stelmach, 1982). Such stage models form a useful heuristic for the organisation of the body of knowledge although there is considerable debate as to how well such approaches actually represent perception and action in practice (Carello et 4 37th Annual Conference Ergonomics Society of Australia Inc. al., 1984) or indeed how well they assist in forward conception of expertise (Abernethy, Burgess-Limerick & Parks, 1994). Within each of the sections that follow consideration is given to key findings on the nature of expert-novice differences (if any) within each of the performance components, key methodologies used to elucidate the differences, and the possible ramifications of this knowledge for practicing ergonomists. Expert-Novice Differences in Sensory Information Processing: The sensory receptors within the human body (e.g., sophisticated receptors such as the retina in the eyes) are responsible for transducing selected physical signals in our surrounding environment (e.g., light waves) into nerve impulses that may be processed and interpreted by our brain and nervous system. Given that there are significant individual differences in the acuity of different sensory receptors, and that it is obviously impossible to respond adequately to signals that cannot be reliably sensed, there has been considerable research interest in documenting the range of human sensory capabilities and in examining whether individual variability in these capabilities is, in any way, systematically related to task performance. Such research typically involves the examination of basic sensory properties using standardised test protocols and generic stimuli such as the letter recognition tasks and checkerboard resolution tasks used in the optometric assessment of static visual acuity. The research to date on sensory information processing supports two conclusions, each of which has significant implications for the ergonomist. The first, unsurprising, conclusion is that poor sensory reception can limit performance - people with visual defects perform poorly on tasks that require high visual resolution; people with impaired vestibular sensation perform poorly on tasks (such as flying) that require precise and rapid adjustments of whole-body orientation. Such an observation clearly suggests an important place for occupational screening of essential sensory properties and, where defects are observed, a place for correction (as in the case of hearing aids for auditory deficits). If occupational screening is to be undertaken however it would appear imperative that the screening protocols used be carefully selected in relation to the task to be undertaken. For example, using static visual acuity screening tests for tasks, like car driving, that require dynamic visual information pickup may be of limited utility, especially when the correlation between individual differences in dynamic and static visual acuity is poor. A second, perhaps less obvious, conclusion from the research to date on basic sensory properties is that experts are not systematically characterised by supra-normal sensory skills. In the main, the basic sensory properties of the expert, when assessed using standardised means, are indistinguishable from that of the remainder of the population. Consequently approaches that attempt to improve task performance through generalised sensory training (such as the generalised visual training approaches advocated by many behavioural optometrists) are unlikely to be effective because they address a facet of performance that is not typically the limiting factor. Controlled studies of generalised visual training in sport, for instance, support the contention that while it is possible to enhance some aspects of basic sensory functioning through repetitive practice this does not then translate to enhanced sports performance (Abernethy et al., 2001; Wood et al., 1997). The same is likely to hold true for most work tasks. Expert-Novice Differences in Perception: Perception is the active interpretation of raw sensory information for the purposes of decision-making and responding. Perception is taskspecific and measures of perception that are task-relevant reveal significant individual 5 Better Integration 27-30 November 2001 differences that are systematically related to the level of expertise. Experts across a range of domains, including ergonomics, show, relative to lesser skilled individuals, superior capacity to discriminate different perceptual events (Blignaut, 1979), superior capacity to recognise patterns from within but not beyond their domain of expertise (Chase & Simon, 1973; Fiore et al., 2000; Howard & Kerst, 1981), and a superior capacity to anticipate forthcoming events on the basis of limited preview information (Abernethy, Wann & Parks, 1998). Approaches combining visual simulations with methodologies such as temporal and spatial occlusion of selective display features have demonstrated that these differences in pattern recognition and anticipation are due to the capacity of the experts to utilise different, and additional, sources of information to that which novices are able to use (Abernethy, 1999; Abernethy et al., 2001). The findings from studies measuring eye movement behaviour (visual search patterns) are less systematic. A number of studies demonstrate significant expert-novice differences in both the location and duration of the ocular fixations made while undertaking domain-specific tasks (e.g., Bellenkes et al., 1997; Kundel & LaFollette, 1972); others however fail to demonstrate systematic expertise-related differences or demonstrate differences in information pick-up that are not matched by differences in visual search strategy (Abernethy, 1988, 1990; Helsen & Pauwels, 1993). This latter observation suggests that it is seeing (the active processing and interpretation of visual information) rather than looking (the orientation of the eyes to different parts of the display) that is the limiting factor to expert perception. The evidence available makes a strong case for the potential to enhance the acquisition of expertise through systematic and strategic training of pattern recognition and through instructional approaches directing selective attention to key information sources. There is some promising preliminary evidence, primarily from sports tasks, that key perceptual attributes can indeed be trained, with particular evidence for the beneficial role of video-based training in hastening the acquisition of anticipatory skill (Starkes & Lindley, 1994; Williams & Grant, 1999). A major challenge to the acceleration of perceptual skill development, however, lies with the fact that perceptual expertise appears to be largely acquired implicitly, without the direct conscious (or verbalisable) knowledge of the performer (Magill, 1998; Merikle, 1992). Traditional approaches, relying heavily on verbal instruction and concentrated explicit attention to key learning features, may therefore be contraindicated and alternative approaches will need to be developed. There is a less compelling case at this time for attempting to have lesser skilled performers learn by modelling the visual search patterns of experts and indeed the few studies which have attempted to do so have reported only very modest success (e.g., Papin, 1984). Expert-Novice Differences in Cognition: Studies of expertise in cognition have utilised a variety of paradigms from cognitive psychology, including think aloud protocols, categorisation and re-sequencing tasks, and direct tests of knowledge. Across this body of work a number of systematic expert-novice differences have emerged. Experts are typically faster at problem-solving, display superior short-term and long-term memory for material, have superior knowledge of relevant facts (declarative knowledge) and procedures (procedural knowledge), see and represent problems at a deeper, more principled, level, and spend a considerable period of time analysing problems qualitatively before arriving at a solution (Gilhooly & Green, 1988; Glaser & Chi, 1988; Ye & Salvendy, 1996). The expert’s advantage is almost always confined to their particular domain of expertise and not generalisable to other domains. 6 37th Annual Conference Ergonomics Society of Australia Inc. There have been some suggestions that the acquisition of skill may be hastened by providing learners with exposure to the cognitions of experts as they perform the same task or by having the learners adopt the mental models (procedural knowledge structures) of experts but the evidence for such approaches being advantageous is scant (but see Bellenkes, 2000). In practical terms information regarding the knowledge structures of experts is more frequently used in system’s design. Systems may be configured in such ways as to either facilitate all users following the decision-making path of the experts (Hanisch et al., 1991) or to remove, as much as possible, the need for specialist knowledge. Expert-Novice Differences in Action Production: In tasks that are time constrained and rapid responding is important, systematic expert-novice differences are generally evident. Where classical choice reaction time situations are involved (i.e., multiple event options each with a unique associated correct response) experts typically show faster decision-making (information-processing) rates although their speed of responding in situations where there is no uncertainty (simple reaction time) is generally indistinguishable from that of the novice. The faster information processing rates of experts are likely attributable to superior utilisation of event probabilities – any advance knowledge of one event being more or less probable than a competing event reducing the processing load. Importantly, in both choice reaction time tasks and in tasks that require rapid serial responding, experts are constrained in the same fundamental way as novices. The essential relationships between uncertainty and reaction time (the so-called Hick-Hyman Law) and between inter-signal interval and reaction time (the phenomenon known as psychological refractory period) are equally robust in experts as they are in novices. The superior performance of experts in these situations is simply a function of operating more efficiently within the limits of these inherent processing constraints. The most effective means of combating these inherent constraints, of course, is through task modification. The use of highly compatible display configurations and task designs that minimise spatial and temporal uncertainty are effective, and now commonplace, means of eliminating performance impairments associated with choice reaction time and psychological refractory period delays (Proctor & Zandt, 1994; Wickens, 1992). In terms of actual movement production, both the kinematics (patterns) and kinetics (underlying forces) of the movements performed by experts display a greater consistency than is typically evident in the movements of novices. Experts, moreover, more effectively utilise the external forces (such as gravitational and reactional forces) available within some movements. This allows experts to restrict their use of muscular force to only those phases in the movement where it is needed and can be provided effectively (Fowler & Turvey, 1978). Novices, in contrast, tend to supply muscular force more or less continuously throughout a movement, often in opposition to, or as an unnecessary supplement to, external forces. With practice, the underlying neuromuscular recruitment patterns become more discrete as muscular effort is recruited more efficiently. This efficiency underpins the greater fatigue resistance and ease of movement often described in relation to expert performance. Concomitantly, the acquisition of expertise is also frequently accompanied by a transition from initial freezing of many joints, through co-contraction of antagonist muscle groups, to a state of increasingly independent control over joints distant from the prime movement (Vereijken et al., 1992). This progressive freeing of degrees of freedom in movement control permits the subtlety of movement control inevitably associated with the motor performance of the expert. Expertnovice differences in movement control are frequently explicable in terms of the expert’s 7 Better Integration 27-30 November 2001 movement pattern being more biomechanically efficient and this holds true for ergonomic tasks as fundamental as those involved in manual lifting and materials handling (Gagnon, 1997; Gagnon et al., 1996). Some attempts have been made to provide feedback on selected movement kinematics, kinetics or neuromuscular recruitment patterns as a means of accelerating the learning of expert movement patterns but as yet there is limited evidence to demonstrate that this is effective (Schmidt & Lee, 1999). Expert-Novice Differences in Attention: It is well documented that one of the defining characteristics of experts is their increased automatisation of actions and their corresponding capacity to apparently handle two or more tasks concurrently with relative ease (Schneider & Fisk, 1983). In the workplace the automatisation of action is best demonstrated through the use of dual-task methodologies. As the name implies, the dual-task method requires people to undertake two tasks simultaneously – a primary task, which is typically the fundamental work task of interest, and a secondary task, which may be a reaction time task, a verbal-cognitive task or another motor task. The dual-task method requires that performance on the primary task be given priority (such that primary task performance remains at the same level in the dual condition as it does when performed alone). If this instructional condition is followed then performance on the secondary task can be used to measure (i) the overall attentional demand of the primary task (more difficult tasks will be associated with poorer secondary task performance), (ii) temporal variation in the attentional demands of the primary task (peak attention demands in the primary task are more or less contemporaneous with troughs in performance on the secondary task), and (iii) the relative attentional demands that common primary tasks place upon different people (Abernethy, Summers & Ford, 1998). Dual-task methods have been used extensively in ergonomics (Wickens, 1992) with consistent demonstration of superior dual-task performance by experts (e.g., Brouwer et al., 1991). Increased automatisation of primary task movement control by experts creates a significant functional advantage for them in being able to attend simultaneously to other surrounding events or concurrent tasks. Automatisation of action is not without its drawbacks however – among these are a greater propensity for automised errors, a reduced conscious awareness of control, and greater resistance to skill modification or correction of ‘in-grained’ movement patterns (Reason, 1990). Interestingly, attempts to reduce task workload by mechanical automation (e.g., by the inclusion of automated aids and decision support tools in aircraft cockpits; Mosier et al., 1997) are also not unproblematic. Expert-Novice Differences in Feedback Utilisation: There is some evidence (Glaser & Chi, 1988) that experts are superior at self-monitoring i.e., they are highly skilled in detecting (and correcting) errors in their own skill production. Novices, in contrast, are highly dependent upon external feedback as the principal basis for error detection and correction. In many ergonomic settings, tasks and machinery are configured so as to provide feedback signals (e.g., warning signals when particular bandwidths of error tolerance have been infringed), thereby removing the demand for human feedback monitoring and, in large part, negating the expert advantage. However, in situations where such feedback provision is not built into the task design, facilitating the development of expert-like self-monitoring may be important. While the existing training dogma is that feedback is essential for learning and the more feedback the better, the regular inclusion of no-feedback practice trials within the skill learning schedule may well be important as a means of fostering skilled capabilities to utilise intrinsic forms of feedback information. 8 37th Annual Conference Ergonomics Society of Australia Inc. 3. SOME CONCLUDING COMMENTS While much is now known about the characteristics that distinguish expert performers from lesser skilled ones, knowledge about how to possibly facilitate the transition from novice to expert is still largely based upon inference. In an era where evidence-based practice is rightfully increasingly seen as important, there is a clear need (and opportunity) for systematically examining the efficacy of the kind of interventions to training, task design and systems development that an expertise model might suggest. There are many compelling reasons for practicing ergonomists to remain conversant with advances in the expertise field, just as there are for expertise researchers to look increasingly at the workplace as an attractive venue for advancing both practical and theoretical understanding of expert performance. 4. ACKNOWLEDGMENTS The ideas presented here have been shaped by discussions (both formal and informal) over many years with colleagues and postgraduate students – although any errors in interpretation are mine not theirs. The funding support of the Australian Research Council, Worksafe Australia, and the Australian Sports Commission is greatly appreciated. 5. REFERENCES Abernethy, B. 1988. Visual search in sport and ergonomics: Its relationship to selective attention and performer expertise. Human Performance 1: 205-235. Abernethy, B. 1990. Expertise, visual search and information pick-up in squash. Perception 19: 63-77. Abernethy, B. 1993. Searching for the minimal essential information for skilled perception and action. Psychological Research 55: 131-138. Abernethy, B. 1999. The 1997 Coleman Roberts Griffith Address. Movement expertise: A juncture between psychology theory and practice. Journal of Applied Sport Psychology 11: 126-141. Abernethy, B. in press. 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Hillsdale, NJ: Erlbaum. pp. xv-xxviii. Hanisch, K.A., Kramer, A.F., and Hulin, C.L. 1991. Cognitive representations, control, and understanding of control systems: a field study focusing on components of users’ mental models and expert/novice differences. Ergonomics 34: 1129-1145. Helsen, W. and Pauwels, J.M. 1993. The relationship between expertise and visual information processing in sport. In J.L. Starkes and F. Allard (Eds.) Cognitive issues in motor expertise. Amsterdam: Elsevier. pp. 109-134. Hoc, J-M., Cacciabue, P-C. and Hollnagel, E. (eds). 1995. Expertise and technology: Cognition and human-computer interaction. Hillsdale, NJ: Erlbaum. Howard, J.H. and Kerst, S.M. 1981. Memory and perception of cartographic information on familiar and unfamiliar environments. Human Factors 23: 495-504. Leibowitz, J. 1990. The dynamics of decision support systems and expert systems. Chicago: Dryden Press. Kantowitz, B.H. 1989. 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Use of the NAC Eye Mark by radiologists. In A.G. Gale and F. Johnson (Eds.). Theoretical and applied aspects of eye movement research. Amsterdam: NorthHolland. Proctor, R.W. and Van Zandt, T. 1994. Human factors in simple and complex systems. Boston, MA: Allyn and Bacon. Reason, J.T. 1990. Human error. Cambridge, UK: Cambridge University Press. Schmidt, R.A. and Lee, T.D. 1998. Motor control and learning: A behavioral emphasis. (3rd ed.). Champaign, IL: Human Kinetics. Schneider, W. and Fisk, A.D. 1983. Attention theory and mechanisms of skilled performance. In R.A. Magill (Ed.). Memory and control of action. Amsterdam: North-Holland. pp. 119143. Slatter, P.E. 1987. Building expert systems: Cognitive emulation. Chichester, UK: Ellis Horwood. Starkes, J.L. and Lindley, S. 1994. Can we hasten expertise by video simulations? Quest 46: 211-222. Stelmach, G.E. 1982. Information-processing framework for understanding human motor behavior. In J.A.S. Kelso (Ed), Human motor behavior: An introduction. Hillsdale, NJ: Erlbaum, pp. 63-91. Vereijken, B., Emmerik, R.E.A. van, Whiting, H.T.A., and Newell, K.M. 1992. Free(z)ing degrees of freedom in skill acquisition. Journal of Motor Behavior 24: 133-142. Wickens, C.D. 1992. Engineering psychology and human performance (2nd ed.). New York: Harper Collins. Williams, A.M. and Grant, A. 1999. Training perceptual skill in sport. International Journal of Sport Psychology 30: 194-220. Wood, J. and Abernethy, B. 1997. An assessment of the efficacy of sports vision training programs. Optometry and Vision Science 74: 646-659. Ye, N. and Salvendy, G. 1996. Expert-novice knowledge of computer programming at different levels of abstraction. Ergonomics 39: 461-481. 12 37th Annual Conference Ergonomics Society of Australia Inc. Ron Cumming Memorial Lecture Are Ergonomics, Economics and Ethics Mutually Exclusive? Maurice Oxenburgh Consultant and Guest Research Scientist at the National Institute for Working Life (Sweden) ABSTRACT As ergonomists we need to be aware of our clients’ economy – will our recommendations improve working conditions and be cost effective? We need also to be aware of ethics – are we improving the health of workers or just pleasing the client (we need to eat too)? In Dr Oxenburgh’s first book that dealt with cost effectiveness in ergonomics interventions the question arose that if the intervention is not cost effective, do we not do it? In his forthcoming book (written in collaboration with Pepe Marlow and Andrew Oxenburgh) and the subject of his lecture, he deals with this apparent conundrum. 13 Better Integration 27-30 November 2001 14 37th Annual Conference Ergonomics Society of Australia Inc. Getting to Zero-Lift in Washington State Nursing Homes: Researching an Intervention Kathleen A. Rockefeller SHARP, Washington State Department of Labor & Industries, Olympia WA Barbara A. Silverstein SHARP, Washington State Department of Labor & Industries, Olympia WA Keywords: nursing homes, resident handling, ergonomics, intervention research ABSTRACT Researchers in occupational safety and health strive to identify and quantify risks for people at work, while practitioners try to bring about changes in the work environment to improve working conditions. What appears efficacious in the lab or in theory may not always be effective in practice. Careful intervention research plays an important role in attempts to understand this gap. Yet the opportunity to study industry wide interventions is all too rare. This paper describes an intervention study in Washington State that took advantage of a unique opportunity for government and industry to work together in an attempt to address an important health and safety problem. The goal of the study was to assess the implementation of zero-lift programs in nursing homes across the state and to evaluate changes in the incidence and severity of injuries to employees, particularly nursing assistants (NACs). Sources of data and methods of collection will be described, along with a discussion of the process and initial results. 1. INTRODUCTION As knowledge about exposure to risk factors for work-related musculoskeletal disorders increases, occupational safety and health practitioners should try use this information to design and implement effective interventions in order to decrease exposure. Indeed, the National Occupational Research Agenda (NORA) musculoskeletal group identified intervention studies of engineering controls and work organization improvements as a high priority. Yet, intervention research is difficult to do and presents numerous potential problems and pitfalls. Schulte et al (1996) suggest that the challenge inherent in intervention research is to conduct studies that remain credible where rigorous experimental research methods are not feasible. Some of these methodological problems include: lack of a contemporaneous control or comparison group; lack of randomization; lack of a placebo intervention; low statistical power; concerns about reliability and validity of measures; secular trends not accounted for; and traditionally low participation and/or follow up rates. A few additional concerns should be mentioned. Ideally, evidence of intervention efficacy exists prior to studying its effectiveness. There should be a logical mechanism by which the intervention is proposed to work. There should also be an explicit model outlining the proposed process by which the intervention might work. Without a model based on theory and evidence of efficacy, understanding about how an intervention works (or, perhaps more 15 Better Integration 27-30 November 2001 importantly, does not work) is limited. Working with a model helps to target an intervention to specific problems and specific audiences and to suggest what data is needed and methods for data collection. The intervention described here was designed to target the high rates of injury reported by personnel in nursing home facilities. Caring for others is important and demanding work. Among nursing personnel, high rates of musculoskeletal injuries have consistently been reported. These injuries, in turn, appear to be related to patient (resident) handling activities. Biomechanical research presents strong evidence that the physical act of patient handling results in forces the on lumbar spine of the handler that are capable of causing tissue damage. There is additional evidence that reducing these loads on the low back would decrease the risk of injury. To this end, the use of mechanical lifting devices has been encouraged as one means to decrease exposure to these potentially injurious loads. The philosophy of using equipment to minimize the lifting of patients has been termed “zero-lift.” Long-term care facilities, or nursing homes, in Washington State have reported a high incidence and severity of work-related musculoskeletal disorders among their employees. The Department of Labor & Industries (L&I), a Washington State agency, manages the State’s exclusive workers’ compensation system. All employers pay into a state fund, with the exception of those who have qualified for self-insured status. The Department also manages the OSHA plan for the State. The Safety and Health Assessment & Research for Prevention (SHARP) group is located within Labor & Industries, and is charged with researching occupational safety and health concerns, as well as serving as a knowledge resource for the agency. In keeping with its stated goal of reducing work-related hazards, illnesses, and injuries, Labor & Industries developed the Hazard Impact Partnership (HIP) to work with employer groups on strategies to decrease hazards in the workplace and to reduce injuries. Agency data was used to help set priorities by identifying industries with high rates of workers’ compensation claims. Since nursing homes had very high rates and counts for work-related musculoskeletal disorders, the industry became the first target for a HIP initiative. The initiative was composed of several strategies. The primary strategy was a financial incentive to encourage nursing homes to invest in better lifting equipment and to implement zero-lift programs. Labor & Industries offered a one-time, up-front, 15% discount on workers’ compensation premiums to nursing homes that applied for the discount and agreed to its requirements. In return, the facilities would use the funds saved to purchase equipment and to implement related policies, procedures, and training. The study thus took advantage of a unique opportunity for government and industry to work together in an attempt to address an important health and safety problem. The short-term goal of the intervention was to encourage nursing home facilities to invest in equipment for resident handling as well as to implement the components of zero-lift programs. The desired long-term outcome was a reduction in the incidence and severity of work-related musculoskeletal disorders among employees in nursing homes, particularly nursing assistants (NACs). The underlying model for the intervention is illustrated in Figure 1. Table 1 describes the five hypothesized primary components of a successful zero-lift environment, and with their key elements. Data collection sought to obtain information on these 16 37th Annual Conference Ergonomics Society of Australia Inc. components, in order to study the importance of their respective contributions to the outcomes of the intervention. 17 Better Integration 27-30 November 2001 TABLE 1: ZERO-LIFT: FIVE PRIMARY COMPONENTS AND KEY ELEMENTS 1. EQUIPMENT Have an adequate # of total lifts, sit-to-stand lifts, and other devices to suit the resident population and staff AND/OR have defined and approved plans to obtain such equipment Have an adequate # of repositioning devices (e.g., low-friction “slipp” sheets, etc.) Processes in place for: o Keeping equipment easily accessible to staff o Keeping equipment charged & in good working condition o Sling cleaning and inspection o Equipment maintenance 2. TRAINING Training on equipment is developed and integrated into overall training and staff development plan Training includes “hands on” practice with opportunities for feedback and coaching Training on equipment is part of orientation AND regular on-going sessions Regular skills check are conducted ALL nursing staff know how to use equipment (not just NACs) Strategies for managing difficult residents offered Assessment of resident function takes into account availability of equipment Up-to-date information on transfer status easily available to NACs 3. POLICIES, PROCEDURES, ENFORCEMENT Have policies and procedures for resident handling, including expected use of equipment o All employees aware of policies o Employees follow policies and procedures o System is in place for correction and coaching; progressive discipline as appropriate 4. INJURY INVESTIGATIONS AND MEDICAL CASE MANAGEMENT o Accidents are investigated to better understand how they occurred o Facility actively involved with the medical case management of workers who are injured o If a third party administrator (TPA) is involved, they know about the equipment available at facility o Alternative “light” duty work available o Physicians know about the equipment available at facility 5. MANAGEMENT COMMITMENT AND EMPLOYEE INVOLVEMENT Funds allocated in the budget for zero-lift program, both for start-up and on-going Employees, especially NACs, are involved with design and implementation of zero-lift Management team understands and supports concept of zero-lift Employees, especially NACs, are involved with selection of equipment Someone is accountable for zero-lift program Employees understand and support concept of zero-lift 2. METHODS The primary sources of data for the study are listed below: 1. Written surveys were developed in order to assess the degree of implementation of zero-lift programs in Washington State. Surveys were mailed to all long-term care facilities in the state meeting the study definition (n=257, 252, and 245 for Years 1, 2, and 3, respectively). The Year 1 survey was considered the baseline survey. Both quantitative and qualitative data were obtained from responses to the surveys. 18 37th Annual Conference Ergonomics Society of Australia Inc. 2. Site visits to facilities were conducted at baseline and one year follow-up to assess the reliability of survey responses and to obtain more in-depth information about resident handling policies, procedures, and programs. Visits were conducted at the facilities receiving the financial incentive (“premium discount” n=34) and at a group of facilities not targeted for the incentive (“comparison” n=20). Interviews were conducted with a number of employees (administrator or director of nursing services, staff development coordinator, members of the safety committee, and nursing assistants). Interviews were focused on obtaining information about resident handling practices at the facilities; however, interviewers also probed for additional information about the overall environment at the facility. Again, both quantitative and qualitative data were obtained, with the interviews providing a particularly rich source of qualitative data. 3. Work sampling observations, using the PATH (Posture, Activity, Tools, Handling) method of work analysis, were recorded at sub-samples of both premium discount (n=8) and comparison facilities (n=8). This was done to learn more about the exposure to postures and tasks during normal work activities. 4. Since nursing assistants are the targeted “end users” for using equipment to handle the residents in their care, we wanted to learn more from the nursing assistants themselves about their feelings and beliefs regarding the use of mechanical transfer equipment. The theory of planned behavior, as suggested by Ajzen (1980), supplied a feasible model to investigate the perceptions of the nursing assistants, and a survey was designed utilizing a framework derived from the model. Although the low response was disappointing, this part of the evaluation provided some intriguing information and ideas for further research. 5. Finally, data about the incidence and severity of work-related musculoskeletal disorders among nursing home employees were obtained from the workers’ compensation database at Labor & Industries. 3. RESULTS The response rates for the surveys were 85%, 96%, and 91%, respectively. From the surveys, a picture of zero-lift environments across the state was obtained. A. EQUIPMENT Over the three-year period of the study, there was an overall marked increase in the amount of mechanical equipment available for handling residents in nursing home facilities in Washington State. As expected, the amount of older manually operated equipment decreased over the same time frame. 19 Better Integration 27-30 November 2001 TABLE 2: DESCRIPTIVE STATISTICS OF NUMBER OF PIECES OF EQUIPMENT REPORTED IN THREE STATEWIDE SURVEYS 1998 1999 2000 MEANS & STD DEV mean sd mean sd mean sd 1.39 1.42 1.28 1.53 0.93 1.30 Hand operated total lifts 1.09 1.52 1.71 1.76 1.95 1.70 Mechanical total lifts 0.34 0.81 0.83 1.41 1.22 1.57 Sit-to-stand lifts When the facilities in the premium discount group were compared to all other facilities, the reported changes were more marked in the discount group, and the difference between the two groups was statistically significant. TABLE 3: MEAN NUMBER OF PIECES OF EQUIPMENT IN THREE ANNUAL SURVEYS REPORTED BY THE TWO STUDY GROUPS hand operated total lifts mechanical total lifts sit-to-stand lifts S1 S2 S3 S1 S2 S3 S1 S2 S3 1.47 0.94 0.58 0.87 1.88 premium discount 2.48 0.17 1.91 2.73 1.38 1.34 0.99 1.13 1.68 all others 1.86 0.37 0.65 0.96 B. POLICIES The presence of policies and procedures is part of standard operations in long-term care facilities, and is required for licensure. In our surveys and visits, there may have been some definitional uncertainly over what constituted a “policy” versus a “procedure” – often, this was defined differently at different facilities, and by different ownership. ALL facilities reported some sort of “standard practice” with respect to handling residents, whether or not this was also termed a policy or procedure. All facilities also reported mechanisms for dealing with unsafe or undesirable actions of employees. Over time, it was seen that as the types of pieces of equipment increased, so did the tendency to state that there were “policies” covering its usage; e.g., if a facility had no sit-to-stand lifts, it would not report having a policy addressing this type of equipment. Once equipment was obtained, then policies were developed and implemented. By Survey 3, the majority of facilities rated themselves as having most of the elements of the policy component. C. TRAINING Like policies and procedures, training of employees is required and is basically built into standard operating procedures. As practices change (e.g., a new piece of equipment is obtained, new regulations introduced), it is expected that employers will train employees. In Survey 3, the majority of the facilities rated themselves as having most of the elements of the training component. D. MANAGEMENT COMMITMENT AND EMPLOYEE INVOLVEMENT This component continued to be an elusive one to capture in measures. Over the three years of the study, it became increasingly apparent that the turnover of management personnel (particularly the administrator, director of nursing services, and staff development coordinator) was related to an atmosphere of stability versus turmoil at a given facility. Management turnover tended to have a destabilizing effect on programs at a facility, including zero lift. Anecdotally, this was expressed by the risk manager for a chain of facilities with seven nursing homes in the premium discount group. He stated that every time 20 37th Annual Conference Ergonomics Society of Australia Inc. there was a change in personnel, he needed to visit the facility to build up support (again) for the zero-lift program. E. WORK SAMPLING OBSERVATIONS The primary task of interest was resident handling. Activities related to this task were defined as “hands on” activities occurring while transferring and repositioning residents, changing their clothes, or administering peri-care. At baseline, for all facilities combined, resident handling accounted for 22.8% of the task observations. Other activities related to caring for residents accounted for another 45.1% of the observations. Clearly, the majority of the nursing assistant’s time is spent in direct care of residents. Postures of the back and shoulder were more likely to be non-neutral during resident handling than any other category of task. With respect to exposure to multiple risk factors at once, postures while handling loads were examined. When nursing assistants were handling loads of more than 23 kgs, back postures were likely to be non-neutral, and this exposure was more likely to occur during resident handling than during any other task. F. NAC SURVEY According to the theory of planned behavior, a person’s beliefs about the outcomes of a behavior will have an effect on the likelihood of the behavior occurring. Nursing assistants were asked about the likelihood of the following outcomes associated with the use of equipment to handle residents in their care. TABLE 4: LIKELIHOOD OF BEHAVIORAL BELIEFS OF NURSING ASSISTANTS How likely or unlikely is it that very somewhat somewhat very using mechanical transfer likely likely likely equipment to move residents will: unlikely unlikely unlikely take more time? 5.6 7.5 8.8 24.4 30.0 23.8 be uncomfortable for resident? 5.7 17.2 14.6 40.8 14.0 7.6 decrease chance of hurting my back? 5.0 6.9 2.5 8.1 18.8 58.8 be noticed by my supervisor? 8.6 15.2 14.6 16.6 27.2 17.9 require help from my coworkers? 8.9 21.0 12.7 18.5 19.1 19.7 Frequency of responses in category It has been suggested that feelings of self-efficacy, or beliefs about one’s ability to perform a given behavior, are also important determinants of behavior. The nursing assistants were asked a numbers of questions about their perceived abilities to handle situations associated with the use of equipment to handle residents in their care. Overall, they indicated feeling quite confident when the situation required their own personal knowledge and skills (knowing how to use the equipment and being able to explain to residents what they were doing), but were less confident when the situation involved factors more out their immediate control, such as being able to find the equipment when needed. So, while the low response limits the ability to generalize, the results of this survey contain some intriguing clues and avenues for further investigation. For example, the data suggested that supervisors and coworkers might not provide as important motivation for the use of equipment as is sometimes suggested. In addition, it appears that barriers to use of the equipment as perceived by the nursing assistants differ from those perceived by management 21 Better Integration 27-30 November 2001 personnel; for example, while the issue of requiring more help is frequently suggested as a problem by management, a good 43% of the nursing assistants felt the use of lifting equipment would be unlikely to require more help from coworkers. G. WORKERS’ COMPENSATION DATA Data on injury claims filed by workers in nursing homes were extracted from the workers’ compensation database at Labor & Industries. Trends for incidence and severity were analyzed and compared. Initial results were encouraging and further analysis is currently underway. The risk manager for a chain of nursing homes that had facilities in the premium discount group shared information about their individual results. Payback on their investment in appeared to take place within 6-12 months after receipt of the funds. 4. DISCUSSION Implementation of a zero-lift environment requires both the requisite equipment and an atmosphere where its use is expected and facilitated. If the presence of equipment is to have a chance at affecting risks of injury, the equipment must be used correctly and consistently. It is important to consider environmental barriers to the implementation of health and safety programs. The long-term care industry is currently in a state of constant pressure and change. Maintaining adequate staffing is a severe challenge. High rates of turnover of both management and staff make it difficult for programs to achieve stability. Residents are sicker and reimbursement levels are less. Individuals in the industry perceive a number of critical barriers to decreasing injuries related to resident handling. Researchers and practitioners need to understand these views from the perspective of those in the industry if efforts to improve working conditions are to be successful. Attempting to address these barriers will take creativity along with relevant data and participation of employees. This study attempted to address and minimize some of the problems that can plague intervention research. “GETTING TO ZERO” STUDY Had a comparison group No randomization Two other interventions offered & studied Job modification Distribution of information on zero-lift (video package) Low statistical power Adequate statistical power Reliability and validity of measures Mixed; some stronger than others Secular trends not accounted for Workers’ compensation data available for analysis of trends Low participation and follow-up Excellent response rates for surveys rates Minimal loss for follow-up site visits Confounding variables Controlled in analysis: size of facility, baseline claims rates and amount of equipment, staffing, geographic region POTENTIAL PROBLEM No control or comparison group No randomization No placebo intervention 22 37th Annual Conference Ergonomics Society of Australia Inc. 5. CONCLUSIONS Nursing home facilities in Washington State did take advantage of a financial incentive to purchase additional lifting equipment and to implement components of a zero-lift environment. In theory, the use of these devices should decrease exposure to potentially injurious forces inherent in resident handling and hopefully decrease injuries to workers in nursing homes. Although the claims data on injuries need to be followed for a longer period of time, initial results are encouraging. The use of qualitative techniques provided insights that would not have been available by the sole use of quantitative methods. The integration of both quantitative and qualitative techniques should be encouraged in future studies. Learning more about what key decision makers consider convincing and adequate evidence would be invaluable to occupational safety and health practitioners. Researchers should consider theories of health and safety behaviors as another means to understanding outcomes in intervention research. In this study, it was people who bought equipment, enforced policies, conducted training, and used equipment. A better understanding of the roles of individuals in interventions could improve the ability to design and implement effective interventions that reach the desired goals. 6. ACKNOWLEDGMENTS Washington Health Care Association National Institute for Occupational Safety and Health Department of Work Environment, University of Massachusetts Lowell 7. REFERENCES Ajzen I, Fishbein M, 1980, Understanding attitudes and predicting social behavior. (Englewood Cliff, New Jersey: Prentice-Hall, Inc.) Banaszak-Holl J, Hines MA, 1996, Factors associated with nursing home staff turnover. The Gerontologist, 36 (4), 512-7. 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