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Jeffrey Jutai, PhD, C.Psych
School of Occupational Therapy
University of Western Ontario
CANADA N6G 1H1
Ph: (519) 661-2111 ext. 88978
There has been no systematic research to evaluate the quality of life impact of assistive technology. The Psychosocial Impact of Assistive Devices Scale (PIADS) is a 26-item self-rating scale designed to fill the measurement gap in this area. This paper summarizes the results from outcome measurement research using the PIADS and suggests how they can be used to improve the prescription and delivery of assistive technology.
Assistive technology (AT) is designed to provide important functional benefits and improve the quality of life for people who use it. However, research has shown that people will sometimes reject or abandon what seem to be well-designed and functional devices (Cushman & Scherer, 1996; Murphy, Markova, Collins & Moodie, 1996; Phillips & Zhao, 1993; Scherer, 1996). The possible consequences of non-use of prescribed technologies can be very serious. They include the loss of functional abilities of the user, increases in attendant and other care costs, and ineffective use of funds from provider organizations. Assistive technology might be threatening to some people and produce feelings of helplessness, frustration, and loss of control (Kerrigan, 1997). For these reasons, designers and providers need to better understand the psychosocial factors that might determine device adoption, retention and abandonment. Moreover, the field of AT needs measures that can be comfortably included in a comprehensive outcome assessment of AT (Jutai, Ladak, Schuller, Naumann, & Wright, 1996).
Why not use a so-called health-related quality of life measure? A number of published generic and disease-specific "quality of life" measurement scales instruments might be considered for use in assessing AT impact. They have two primary limitations. First, they are too medically oriented. Most assistive devices are not intended to promote health and healing, but rather to improve or restore functional capabilities. Second, they are designed to assess health status or change in health status, and not the impact attributable to any particular form of intervention. They are either not sensitive enough to detect functional or psychosocial changes specific to an AT intervention, or cannot be used with some clients because their functional limitations, although accommodated through AT, are too severe to permit valid assessment using the instrument. In any event, AT is meant to achieve different quality of life outcomes than surgery, physical therapy, and pharmaceutical treatments.
Quality of life is a complex and multidimensional construct. It is dynamic, changing over time and over a person’s life. It arises from a person’s interaction with their environment. It is experienced differently from person to person, but has the same components for everyone. The most important perspective on how AT affects quality of life is the perspective of the device user. We define quality of life impact as the effect of the technology on, "the degree to which a person enjoys the important possibilities of his/her life" (Renwick, Brown, & Raphael, 1994, p.35).
An assistive device will promote good quality of life for the user to the extent to which it makes the user feel competent, confident, and inclined (or motivated) to exploit life’s possibilities. These three key dimensions have been determined empirically to underlie how users perceive the psychosocial impacts of AT.
The Psychosocial Impact of Assistive Devices Scale (PIADS; Day & Jutai, 1996) is a 26-item, self-rating questionnaire designed to measure user perceptions of how assistive devices affect quality of life. The PIADS describes user perceptions along three dimensions: Adaptability (the enabling and liberating effects of a device); Competence (the impacts of a device on functional independence, performance and productivity); Self-esteem (the extent to which a device has affected self-confidence, self-esteem and emotional well being). Scores can range from –3 (maximum negative impact) through zero (no perceived impact) to +3 (maximum positive impact). A number of studies have demonstrated that the PIADS is a reliable, valid, and responsive measure (Day & Jutai, 1966; Day, Jutai, Woolrich & Strong, 2000; Jutai, J., Rigby, P., Ryan, S., & Stickel, S., 2000; Jutai, J., Woolrich, W., Campbell, K., Gryfe, P. & Day, H. (2000), with good clinical utility (Gryfe & Jutai, 1999, 2000; Jutai & Gryfe, 1998). The PIADS is a sensitive measure of the impact of a wide range of ATs, in populations of adults who have various forms of disability and medical condition (Jutai, 1999).
The original validation of the PIADS was through studies of eyeglass users and contact lens users, who were able-bodied apart from their vision problem (Day & Jutai, 1996). Both types of device user reported a positive impact on all three subscales. Contact lens users reported significantly higher impact on Adaptability, Competence and Self-esteem than did eyeglass users, with the largest difference being in the Self-esteem domain. Subsequent research with this population has shown that positive psychosocial impact is sustained over time (Day, Jutai, Woolrich & Strong, 2000), and PIADS scores alone are significant predictors of device retention or abandonment (Day & Jutai, 2000).
Another study examined whether the constructs measured by the PIADS are the same when the scale is applied to users of assistive devices more commonly associated with disability and rehabilitation, such as wheelchairs (Jutai, Gryfe, & Day, 2000). The sample consisted of clients receiving services at a large, hospital-based assistive technology clinic who had a variety of diagnoses including degenerative disease, and brain or spinal cord injury. Factor analysis revealed that essentially the same items that defined the three PIADS subscales in the eyewear study were the items defining the factor structure of the scale for wheelchair users. In other words, the PIADS appears to be measuring the same key dimensions of perceived impact across different populations of device user.
The most extensive clinical investigations using the PIADS have included wheelchairs (manual and powered), voice-output communications aids (VOCAs), computer-assisted writing aids, and electronic aids to daily living (EADLs; known formerly as environmental control devices (Jutai, 1999). Devices designed to support communication and occupational productivity, such as VOCAs and writing aids, seem to produce significantly higher PIADS ratings than wheelchairs, especially on the Competence and Self-esteem subscales (Gryfe & Jutai, 1998). For wheelchairs, the scale appears to be remarkably sensitive to differences in perceived impact associated with manual versus powered models, and the various options for independent control and postural support (Gryfe & Jutai, 2000). Wheelchair options that give the user greater independence in comfort and mobility are perceived as making a bigger impact on quality of life. EADLs seem to make a similar positive impact on both the perceptions of users and the expected benefits reported by nonusers (who have been prescribed EADLs but have not yet received them) (Jutai, Rigby, Ryan & Stickel, 2000). Also, the impact described by EADL users is stable over time.
The PIADS appears to be sensitive to important differences among diagnostic groups in perceived quality of life impact of assistive technologies (Jutai & Gryfe, 1999). When asked to rate their wheelchairs within the first three months of use, users who have a degenerative disease or condition such as amyotrophic lateral sclerosis (ALS) report significantly smaller positive impact than users who have had a brain or spinal cord injury, especially in the Self-esteem domain. The implication is that users with an acquired, but static disability are more likely to perceive that a wheelchair helps improve quality of life than users with a condition that produces deteriorating health.
The PIADS seems to be a responsive measure, that is, able to detect clinically important change over time (Jutai & Gryfe, 1999). PIADS scores of users with ALS were examined at three points in time - before (baseline), within three months, and six months after receiving an assistive device (wheelchair, VOCA, writing aid). The difference in pattern of response to AT intervention across the three device categories was dramatic. The mean baseline scores for wheelchair users for the PIADS subscales were zero or negative, suggesting that this group had little expectation that a wheelchair would improve their quality of life. At first and second assessment however, mean ratings had significantly increased above zero. VOCA users had a small expectation for positive impact, and a response to device use similar to that of wheelchair users at the two follow-up times. Writing aid users began with the expectation that there would be an appreciable positive impact on quality of life. Their ratings increased only slightly after three and six months of device use. A possible explanation for these findings is that those people who are likely to receive these devices more readily anticipate the functional and psychosocial benefits of VOCA and writing aid technologies. Wheelchairs, on the other hand, are more closely associated with the stigma of disability and poor prognosis than the other two technologies in the minds of potential users. With time to adapt to the device, wheelchair users are able to enjoy more of life's possibilities than they might have anticipated. The PIADS can give AT researchers and service providers useful information to help design and prescribe technologies that more effectively match the needs and expectations of users.
A recent study has examined user-caregiver agreement on the PIADS (Jutai, Woolrich, Campbell, Gryfe, & Day, 2000). There was surprisingly good user-caregiver agreement on PIADS ratings for wheelchairs, walkers, writing aids and electronic aids to daily living. Group ratings obtained by proxy, from caregivers, were very consistent with those obtained through user self-report.
Our research suggests that assistive technologies may produce distinct and predictable impacts on user feelings related to quality of life. The PIADS allows for immediate comparisons of devices and users along the same psychosocial dimensions.
The Ontario Ministry of Health and Long-term Care through the Ontario Rehabilitation Technology Consortium has provided funding for this research.
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