Abstract
Little is known about characteristics and driving patterns of drivers with physical disabilities who use vehicle modifications (VMs). We gathered information about, and from, drivers with disabilities who use VMs to better understand their needs and to inform current occupational therapy driver rehabilitation practice. A prospective descriptive cross-sectional analysis of 97 drivers with physical disabilities who used VMs identified that most participants were dependent on wheelchairs for personal mobility and that access to key destinations without independent driver mobility was difficult or impossible. Personal independence facilitated by VM use enhanced community participation, including access to health care and employment. Slightly more than half the surveyed drivers (51%) obtained occupational therapy services for driver assessment and VM evaluation. Participants reported VM safety and maintenance issues, including difficulties obtaining appropriate VMs. Study results highlight the potential value of occupational therapy driver assessments and the need for postimplementation review of VMs.
For many adults, the ability to drive is paramount to enable participation in household, social, and work roles. Driving is considered an instrumental activity of daily living, and changes in driving independence may affect people’s self-perceived health and well-being (American Occupational Therapy Association, 2014; Golisz, 2014). The World Health Organization (WHO; 2009) identified the benefits of personal mobility and road transportation as “increased access to jobs, economic markets, education, recreation and health care, which in turn have direct and indirect positive impacts on the health of a population” (p. 12). Studies examining older driver behavior have found correlations between driving cessation and reductions in out-of-home activities (Marottoli et al., 2000; Ragland et al., 2005). Patomella et al. (2009) explored drivers’ experience after a stroke and found that driving was “a part of the individual’s history and a way of keeping continuity in everyday life’’ (p. 729). Independent community mobility contributes to productivity, quality of life, and community and work rehabilitation and participation for people with disabilities (Pellerito, 2005).
Vehicle design has an impact on ease of use and driver comfort. Herriotts (2005) examined U.K. drivers between ages 60 and 79 yr who used domestic vehicles (N = 1,110) and identified issues with design features related to driver personal mobility, including problems with ingress and egress, and sensory functional limitations. The results underscored the importance of adopting user-centered universal design approaches and clear vehicle design guidelines.
Paine et al. (2007) attempted to develop objective measurement criteria for assessing the suitability of currently available domestic vehicles for older drivers. After considering human factors as well as various safety and usability issues, they concluded that defining optimal universal parameters under all circumstances for all occupants was impossible. They highlighted the importance of considering individual factors such as anthropometry and mobility restrictions when choosing among different standard vehicle configurations. Others have echoed this need for a customized approach to vehicle choice because some parameters that optimize ingress and egress (e.g., for a driver who uses an aide’s assistance to transfer from a wheelchair) may make access to primary vehicle controls more difficult (Ellis & Talbot, 2006).
Role of Occupational Therapy Driver Assessors and Vehicle Modifications
Occupational therapists play an important role in supporting drivers with disabilities to develop or resume driving activities. With appropriate individual ergonomic assessment and the prescription of custom vehicle modifications (VMs), people with limited use of their limbs may be able to drive safely (Di Stefano & Stuckey, 2015). VMs include lowered floors and automatic ramps that provide vehicle access for wheelchair users; simple postproduction add-ons, such as pedal extensions or steering aids; and integrated primary vehicle controls, such as lever brake and acceleration and joy-stick steering systems. In Australia, occupational therapy driver assessors (OTDAs) have supported drivers in attaining independence by means of driver assessment and rehabilitation interventions, including prescribing VMs, since the mid-1980s (Di Stefano & Macdonald, 2010).
Various funding schemes and regulations facilitate Australian drivers’ access to VMs, which might otherwise be impeded because of the substantial costs associated with modifying vehicles. It is essential that VM assessment and provision practices are evaluated to ensure efficient and appropriate service delivery. Prescription should be evidence based and incorporate the needs of this client group so that resources are used effectively and optimal road safety and driver independence outcomes are achieved.
Study Rationale and Significance
Few studies have examined the experience of drivers with disabilities and their use of modified vehicles, a research gap that severely limits current understanding of this group’s needs. A literature search of relevant databases (Embase, MEDLINE, ProQuest, and CINAHL, limited to January 2000–March 2014) using key terms (including vehicle adaptations, disabled drivers, and vehicle technology) yielded only a handful of studies specifically related to VMs. These studies consistently highlighted the need for further research into driver assessment and VM prescription and provision. For example, Henriksson and Peters (2004) surveyed 793 drivers who used VMs to increase knowledge about VM safety. They found that although drivers with disabilities did not have a greater crash risk than the general driving population, there was a need for improved driver training and VM evaluation to ensure appropriate vehicle adaptations.
Other studies have examined the experience of people with disabilities who use assisted technology devices (see, e.g., Lenker et al., 2013) and their lack of awareness of VMs available to accommodate lower limb impairment (Jones et al., 2010). None of these studies have focused on people’s experiences with VMs. Several studies have also highlighted the benefits of driving a modified vehicle in terms of increased community mobility and work participation (Giordano & Dijkers, 2011; Norweg et al., 2011; Tsai et al., 2014), but little is known about actual assessment of and subsequent driver experiences with VMs. Thus, little appears to be known about driver characteristics, the modifications drivers use, and their safety and experience of usability. Such information would inform driver assessment prescription and review processes, risk management, and VM design while developing the evidence base to support professional practice, funding, licensing, and vehicle registration requirements.
The purpose of this study was to address the paucity of information about the characteristics and user experience of drivers with disabilities who routinely use VMs. We sought to describe their characteristics; document their experience with driver assessment and VMs, including benefits and limitations; understand the role of occupational therapy assessment; and examine self-reported impacts of VM use on personal independence and community participation.
Method
Research Design
This study used an exploratory research approach that is appropriate when little is known about a group or phenomenon (Liamputtong, 2010). A literature review was conducted, and a project advisory group (PAG) was established (including OTDAs, representatives of disability advocacy groups, and drivers with disabilities). The PAG played an important role in project governance by informing and validating the content, development, and distribution of the survey and reviewing and ratifying the analysis and application of the study results (Hickson, 2013).
The descriptive cross-sectional study design was based on a sample of VM users who completed a survey. Before implementation of the survey, we trial tested it with 5 drivers with disabilities. They identified usability issues that were then rectified.
The La Trobe University Human Ethics Committee and the management boards of partnering organizations (Disabled Motorists Australia [DMA] and the Australian Quadriplegic Association [AQA]) provided ethics approval.
Participants and Sampling
To be included in the study, participants had to be older than age 17 yr with a physical disability, have been an active driver using VMs within the past 12 mo, and be fluent in English. Explanatory information provided to participants outlined study governance and goals, selection criteria, and operational definitions of key terms (e.g., what constituted a modified vehicle). Return of completed anonymous surveys was accepted as implied participant consent to meet ethics requirements.
Participants were primarily recruited by means of purposive sampling. DMA and AQA, national advocacy groups likely to include members using VMs, were keen to promote research investigating independent driving. They contributed to PAG activities and assisted in survey promotion, distribution, and collection (AQA, approximately 750 members; DMA, approximately 500 members) over a 9-mo period. These organizations emailed or mailed members with study details and options for completion. Participants could (1) complete the survey electronically and return it to the organization by email for deidentification and collation before it was forwarded to the researchers; (2) print out the survey, complete it, and anonymously mail it directly to the researchers; or (3) directly email the researchers to request that they be mailed a hard copy and a self-addressed, stamped envelope for return of the survey. Each participant received only one invitation.
Convenience and snowball sampling (using hard-copy surveys and postage-paid reply envelopes) were used to maximize recruitment (Hissong et al., 2014). All participants were eligible to receive a movie ticket voucher as a token of appreciation. Participants were instructed, and provided with the means, to return surveys and movie voucher requests separately and anonymously. Anonymity was essential to ensure honest reporting without fear of reprisal or reports to the licensing authority.
Data Collection and Analysis
The survey included 19 items (3 closed, 5 open, and 11 that elicited both quantitative data and free-text responses). Sections addressed driver characteristics, self-reported current general physical and psychosocial health status, medical history of a condition leading to a permanent health disability (fixed-response items based on simplified international categories of health conditions; WHO, 2014), the main health diagnosis that led to VM use, and any other health conditions not previously mentioned. Sections also addressed VM prescription, driving and safety-related experiences, perceived benefits of driving with VMs, recommendations participants wanted to offer to others about VM prescription, and any other VM use issues raised by participants. (The survey is available from the first author.)
Quantitative data, analyzed using IBM SPSS Statistics (Version 21; IBM Corp., Armonk, NY), provided descriptive statistics (means, standard deviations, and percentages) for continuous variables. We used χ2 tests to analyze nominal data, with p < .05 regarded as significant. Free-text responses were transcribed verbatim into the database. Direct quotes from these responses were matched to respondents’ demographic details and are included here when relevant.
Results
Participant Characteristics
Ninety-seven completed surveys were returned. Response rates could not be calculated because the DMA and AQA databases do not record the member characteristics required to establish the proportion of members meeting study eligibility criteria. Not all participants completed all survey items.
Drivers (N = 97) were mostly male (66%), age 61 yr or older (64%; mean age = 62.36 yr, standard deviation = 12.29), living with one or more other persons (68%), and in a metropolitan area (72%). The majority rated their physical health as good or very good (67%), with onset of their disability ranging from 2 to 69 yr ago. The major health conditions drivers reported were spinal neurological damage (n = 55), polio (n = 18), musculoskeletal (n = 18), and other neurological (n = 6). These conditions resulted in both legs being paralyzed (52%) or restricted functionally (27%) or with further back or trunk restrictions (32%). The most common other diagnosed health conditions (which did not necessarily affect the need for VMs) were arthritis (21%), vision loss (12%), and hearing loss (10%). Almost all drivers used a wheelchair for mobility (97%) and reported driving as their preferred transport method (90%).
Driving Behavior
The majority of participants drove daily or almost daily (55%). Most independent driving trips (71%) were <1 hr long. Apart from a preference to drive to places that had parking spaces for people with disabilities, most drivers never or only sometimes applied self-regulatory driving practices (e.g., avoided driving under certain weather or traffic conditions) to accommodate disabilities (Table 1).
Driving Patterns (N = 97)
Without independent vehicle mobility, most drivers found it very difficult or impossible to access key destinations: employment (71%; N = 58), family or friends (59%; N = 95), or medical (53%; N = 95) and retail (50%; N = 94) facilities (note that percentages are based on the total number of respondents replying to individual item options). Participants overwhelmingly reported that VMs enabled community participation and independence: “I would not have lived to the maximum of my life if I could not drive” (female participant, age 62). When participants did not want to drive (N = 97), they preferred to ride with friends or family as drivers (47%) or to pay for a taxi (36%). A substantial percentage of participants (27%) indicated they would cancel or postpone plans if they did not want to drive.
Vehicle Modification Provision and Role of Occupational Therapy Assessment
Ninety-five participants responded to items relating to choice of or sources of advice regarding VMs. Sources of advice for VM selection were OTDAs (35%), occupational therapists (37%), driving instructors (20%), vehicle modifiers (23%), and local mechanics (10%). Five reported they independently designed or arranged installation of their own VMs.
In response to the item “What is the most important aspect of making sure the modification is matched to drivers’ needs?” 11% recommended input by occupational therapists. Several reported positive occupational therapy experiences: “[I] took the advice of a very good OT at rehab” (male participant, age 68), “I had help from my OTs and physiotherapist” (male participant, age 75), and “a good OT that can help with driving lessons” (female participant, age 62).
Fifty-one percent of participants reported undergoing an OTDA-specific assessment. This group was more likely to undertake lessons with an instructor and practice using VMs (p < .05). OTDA assessment was not significantly associated with increased opportunities to talk to others about VMs (Table 2). Only 3 participants of the total 97 reported trying out different types of modifications or seeing them in other people’s cars.
OTDA Assessment Variables (N = 97)
Note. OTDA = occupational therapy driver assessors; VMs = vehicle modifications.
Experience of Vehicle Modifications
Participants used different types of VM, including hand controls, steering aids, ramps or hoists, and modified foot controls (Table 3). Most required one (n = 39) or two (n = 28) or, less frequently, three or more VMs (n = 26). Those with spinal cord injuries were more likely to use hand controls (χ2 = 7.51, p < .05). A higher proportion of those with musculoskeletal disorders or amputations were likely to use foot-control VMs than those with spinal cord injury, polio, or neurologically related diagnoses (χ2 = 8.85, p < .05).
Participants’ Experience With VMs
Note. Each driver could use more than one type of VM. M = mean; N/A = not applicable; SD = standard deviation; VM = vehicle modification; WC = wheelchair.
“Other” includes right foot support, cruise control, postproduction additions of automatic window up–down switches, scooter trailer, ROHO® back cushion, lowered suspension, power seat, modified gear stick, and driver air bag deactivation.
The majority were mostly satisfied or very satisfied with VMs used (see Table 3). However, when subsequently asked to report on VM issues, 28 reported safety concerns, and 37 reported breakdown concerns. Participant comments indicated several serious matters, such as “[I’m] aware of the need for maintenance and checking to get optimum performance; have had a collision—inability to apply brakes due to lack of maintenance,” “Velcro steering glove coming off during sharp turns,” “hand control broke,” “accelerator pedal can sometimes drop off,” “modification detachable and has sometimes fallen off,” and “sometimes pedal can fall off while driving.” Six participants reported using very old, potentially unsafe VMs. One stated, “Had same controls for 26 years, concerned about safety” (male participant, age 46). In addition, 3 participants reported using hand controls that no longer met national standards.
Exploration of the relationship between receiving an OTDA assessment and reporting VM-related concerns showed a statistically significant difference for participants who reported concerns with the mental effort involved in VM use. However, no difference was found for other factors (Table 4).
Concerns Related to VMs
Note. Participants noted whether they had a concern with each of their modifications as listed in Table 3 (up to four modifications). Issues for any VMs were recorded as “concerns.” No concerns and nonresponders (n = 8) were recorded as “no concerns.” OTDA = occupational therapy driver assessor; VM = vehicle modification.
Discussion
The participants in our study were mostly older men for whom VMs and driving independently were key enablers supporting community engagement and access to family and friends, employment, and health services. The majority did not self-regulate their driving, other than to consider the availability of parking at destinations. Charlton et al. (2006) surveyed 656 older Australian drivers and also found that participants did not self-regulate their driving, except for limitations in functional ability (e.g., poor night vision resulted in self-imposed limitations on night driving). This finding suggests the possibility that the functional limitations of the drivers surveyed in our study are largely addressed through their VMs, removing the need to self-regulate.
Respondents may, however, have considered only their primary disabilities when answering the self-regulation survey item because the item wording referred specifically to the accommodation of their disabilities. If other factors unrelated to the VMs affected participants’ driving abilities (such as vision impairment), they may well require or already apply other types of self-regulation (e.g., limiting night driving). Whether this was the case is unknown because of the limitations associated with self-reports. Future research could further explore this possibility.
Driving assessments aim to evaluate the driving behavior of drivers with a wide range of health conditions and consist of off- and on-road assessments (Korner-Bitensky et al., 2006). OTDA involvement in driving assessment is an important component of VM provision. In Victoria, Australia, legislation specifies OTDAs as suitable to conduct competency assessments of drivers with medical or disability-related issues. Such assessments are usually a prerequisite for legal use of VMs (Di Stefano & Ross, 2018).
We found that some drivers had adopted VMs several decades before the availability of OTDA driving assessments, and a small number had self-prescribed or self-fitted VMs. Those drivers who did have an occupational therapy assessment were more likely to have received driving lessons, potentially improving their driving and VM safety. A higher proportion of participants who received a driving assessment had concerns about the mental effort needed to operate controls than those who had not been assessed. This finding is not surprising because drivers with both cognitive and physical impairments are more likely to be referred for an OTDA assessment. Benoit et al. (2009) reported an increased demand on drivers’ perceived workload when driving with VMs, reinforcing the need for formal OTDA assessment with attention to matching cognitive demands to user capacity, customized training to integrate and automate new skills, and reassessment when health or disability status changes.
We found no association between OTDA assessment and other factors such as opportunity to trial or discuss VMs or the number of reported safety or breakdown concerns, and only 11% mentioned the occupational therapists’ contribution to matching drivers’ needs with VMs. The positive association found between OTDA assessment and lessons or practice with using VMs suggests that OTDA involvement is important, but the data suggest OTDAs’ role should routinely encompass facilitating access to other VM users and broader VM choices. Although the majority of participants had used VMs for at least 20 yr, we did not specifically elicit information about the model or recency of VM upgrades, only the total years of use. The potential for old mechanical VMs to affect vehicle safety was identified several decades ago (Turner-Stokes et al., 1996). The proportion of participants using obsolete technology is possibly much higher than our results indicate. As a 62-yr-old male participant (who reported 32 yr of VM use) stated, “Recently I attended a Disabled Motorists Association meeting about new adaptions available—I had no idea!” Several authors have advocated that drivers receive sufficient training in the safe use and maintenance of VMs and for mandatory evaluations after VM installation to ensure correct installation and driver proficiency (Pellerito, 2005; Stav, 2004).
Limitations
The results of our study should be interpreted considering the following limitations. Although the use of convenience and snowball sampling methods provided confidential access to the relevant population, it has an inherent bias: Participants may not be a representative sample. Drivers with disabilities who are members of advocacy organizations may be more likely to be proactive and informed regarding VM access. Our findings, however, did not support this possibility; many study participants were not fully informed about VM options. Participants’ age may have influenced their access to OTDA services and VMs as well as their overall knowledge of VMs. Drivers who underwent rehabilitation many decades ago may not have had access to OTDA services or to means (such as the Internet) to acquire updated VM information. It is also likely that in the past fewer drivers had VMs compared with the present. Research with a larger group of younger drivers with disabilities using VMs may produce different results. In addition, we did not screen drivers for significant cognitive limitations; we instead relied on the Driver Licensing Authority periodical medical review process to exclude such drivers from licensure and, hence, from meeting survey inclusion criteria.
Another limitation was the many open-ended survey questions, which in some instances resulted in small response numbers, limiting analyses to predominantly descriptive statistics. As is common with self-report, anonymous surveys, although we asked participants to reply only once, we have no way to verify that participants did so, other than to advise that no duplicates were detected when survey data were transferred to SPSS. In addition, we relied on self-report health and self-regulation information, which may have resulted in underreporting of health or other behavioral or cognitive changes. Seeking input from a collateral source (e.g., doctor, caregiver, spouse) would have enhanced health data reliability. Moreover, because of participant burden considerations, we had to omit additional survey items of interest (e.g., VM nonuse).
Implications for Occupational Therapy Practice
The results of our study have the following implications for occupational therapy practice:
Facilitating access to VMs for people with disabilities is crucial to supporting independence in mobility and community participation.
There is a need to increase awareness of VMs (and emerging technologies) among health professionals, drivers with disabilities, and the public.
OTDAs have a potentially valuable role in ensuring both initial VM prescription (including providing access to trial VMs) and postimplementation review and maintenance to ensure ongoing safety and optimum driver–vehicle fit.
Generalist occupational therapists should routinely inquire about clients’ driving status to ensure drivers with disabilities have regular reviews of their capacity and VMs.
Occupational therapists need to actively promote the OTDA role in VM assessment and prescription and ongoing management of drivers with disabilities to other health professionals and stakeholders.
Conclusion
To our knowledge, this study is unique in its focus on the experience of Australian drivers with physical disabilities who use VMs. We identified new information about VM users, how VMs support community participation, and issues and gaps related to the provision of VMs. This article contributes to greater understanding of the experience of drivers with physical disabilities and can inform professional guidelines and funding to improve VM prescription efficiency and effectiveness. The study also highlights the importance and potential value of OTDA initial and ongoing interventions related to VM provision and highlights possible areas for improvement and research.
Footnotes
Acknowledgments
We thank the participants who completed the surveys; project advisory group members; Oliver Black, for data analysis assistance; and VicRoads, Disabled Motorists Australia, and the Australian Quadriplegic Association, for their in-kind support. We also thank the reviewers for their helpful feedback. Funding for this study was received from the Institute for Safety, Compensation and Recovery Research supported by the Transport Accident Commission and WorkSafe Victoria. Research knowledge translation was also supported through a Churchill Fellowship undertaken by the lead author.