Effective mobility framework: A tool for designing comprehensive O&M outcomes research

Orientation and mobility (O&M) can be understood from two perspectives. On one hand it refers to the professional action of O&M specialists on their clients’ behalf and most of these clients have low vision or blindness. According to a number of professional texts, O&M intervention gives priority to safety, efficiency, independence, and gracefulness in travelling to a desired destination (Hill & Ponder, 1976; Weiner, Welsh, & Blasch, 2010). From the clients’ perspective, O&M is holistic, encompassing such everyday actions as moving around the kitchen to make a meal, hanging out the washing, going to work, or shopping. Holistic O&M programs are targeted to the individual client’s needs and might involve practical training in visual efficiency, self-protection, road safety, mobility aid use, decision making skills, or social access, but in doing so can address any specific issues that might undermine the client’s travel confidence (Deverell, Taylor, & Prentice, 2009).

O&M outcome measures are needed to demonstrate the ways that O&M training impact the everyday lives of people who receive services. The other context that calls for evidence of O&M outcomes is the developing field of vision restoration treatments, for example, retinal prostheses (Schneck & Dagnelie, 2011).

The assessment of functional vision and associated performance can be approached from two directions: parts-to-whole, and whole-to-parts (World Health Organization, 2001). Eye care professionals assess the structure and function of the eye, and this assessment contributes parts-to-whole towards an understanding of functional vision. To date, some O&M outcomes research has tended to use this parts-to-whole approach. Travel speed and contact tallies are used as performance indicators on travel routes that are prescribed by researchers, either in laboratory-based or real world environments (Geruschat, Bittner, & Dagnelie, 2012). However, these measures and methods have not yet produced convincing evidence of the functional value of vision restoration treatments or O&M training, even when participants have reported gaining benefit from the intervention they received (Virgili & Rubin, 2010).

In contrast, an O&M specialist tends to work whole-to-parts, beginning assessment by considering the client’s range of activities and participation in the wider community before identifying the micro elements which impact performance. This assessment process generates abundant qualitative data about functional vision and O&M, but these data are difficult to reduce and compare between unique settings, or pre-post intervention. Some degree of standardisation and measurement is needed to facilitate comparison and analysis of data and the challenge is to introduce standardisation without compromising the essential nature of O&M outcomes (Durward, Baer, & Rowe, 1999).

The disjunction between the research designs used to evaluate O&M outcomes to date, and clients’ real-world O&M experiences, suggests that researchers need to consider how O&M is defined and how best to capture each client’s unique experience of O&M, and then explore alternative ways of measuring O&M performance.

O&M action is complex, and is manifested differently according to each person’s unique vision, abilities, circumstances, lifestyle priorities, and choices (Orientation and Mobility Association of Australasia, 2013). Geruschat et al. (2012) proposed that benefits from a retinal prosthesis might be more evident in orientation than mobility, but the very first text documenting O&M techniques noted that when considering functional performance, mobility and orientation can be difficult to separate (Hill & Ponder, 1976). Physical locomotion from place to place helps to build an understanding of the temporal or spatial relationships between significant objects. In turn, an understanding and recognition of surroundings can foster more confident movement. Thus, O&M outcomes research might be approached from the perspective of either orientation or mobility, but needs to encompass both because of the reciprocity between the two.

Physical action is easier to observe than the cognitive processes involved in orientation, making mobility a more tangible construct to assess. The International Classification of Functioning, Disability and Health (ICF) considers mobility both at the micro level of body structure and function including: joint mobility, muscle power and tone, and involuntary movements – as well as the macro level of activities: lifting and carrying objects, fine hand use, walking, moving around using equipment, using transportation, and driving (World Health Organization, 2003). However, Metz (2000) has identified elements of mobility that also incorporate psychosocial factors and participation: “(1) Travel to achieve access to desired people and places (2) Psychological benefits of movement – of ‘getting out and about’ (3) Exercise benefits (4) Involvement in the local community (5) Potential travel, or knowing that a trip could be made, even if not actually undertaken” (p. 150). Metz’s definition is important since it acknowledges that the traveller is always located in a specific social context, whether other people in the environment are nearby or far away (Robson, 2011). However, orientation is a notable omission from both the ICF and Metz definitions of mobility.

The O&M profession both in Australia and elsewhere does not seem to use any established measures of orientation skills. Instruments such as the Rey-Osterrieth Complex Figure Test (Bennett-Levy, 1984) and the Wechseler Block Design subtest (Wechsler, 1976) were both established many years ago and continue to be used in neuropsychology assessments, but both instruments rely on vision to assess spatial perception. In O&M, when a person has poor spatial skills and tends to get lost easily, vision can be used to find landmarks or signs, to follow other pedestrians, or find by-standers to help. However, vision is not crucial for someone with strongly developed spatial skills to gain and maintain a sense of orientation during travel (Golledge, 1999). Other non-visual information about the environment can serve just as well to detail the traveller’s mental map. Such aspects of low vision or blind mobility as spatial cognition are not necessarily obvious to people who can see (Mettler, 2008) and this makes them more challenging to assess. Tests of spatial cognition and orientation skills which do not require vision are needed to gain a fuller understanding of the relationships between orientation, vision, and mobility in O&M performance.

Approaching O&M holistically means considering participation not just specific activities. Here the notion of “life-space” is pertinent; this notion was proposed in 1936 by Kurt Lewin, who was working in the field of gerontology. Life-space refers to the geographical area a person occupies in the course of daily living and can serve as an indicator of activities and participation (Baker, Bodner, & Allman, 2003). An older person’s life-space might be limited to his aged care home and a weekly outing to the local shops, whereas a middle-aged person’s life-space might be much broader because of her career-related travel interstate or overseas.

Loss of mobility reduces opportunity for participation in social activities and work, volunteering, shopping, healthcare visits, and faith-based activities (McCarthy, 2009). Contraction of a person’s physical and social life-space can lead to social isolation, loss of status and confidence, loss of self-worth, depression, and declines in physical wellbeing (Baker et al., 2003; Horowitz, 2004; Oxley & Charlton, 2009; Oxley & Whelan, 2008). O&M intervention seeks to arrest this contraction of life-space and, if possible, to expand a client’s viable travel options, while also teaching and testing the physical and cognitive skills which are needed to make this travel possible (Deverell, Scott, Battista, & Hill, 2014). Vision restoration treatments seek to serve a similar purpose in expanding life-space and, by association, quality of life.

When investigating whether or not new travel skills or life-space expansion have been achieved through O&M training or vision restoration treatments, a clear understanding of what is involved in O&M, to know what to measure is needed. The aim of this study is to ‘re-scope’ “mobility” from the perspective of both O&M specialists and clients, in order to prompt fresh thinking about the design and selection of tasks and measures which might capture O&M outcomes.

At Bionic Vision Australia (BVA), the clinical research team had the challenge of designing O&M research that could demonstrate the functional impact of BVA’s prototype retinal implant (Ayton et al., 2014). The team wanted to capture comprehensive data about O&M action, even if there were areas of performance that were not easy to measure. Prior to developing a research protocol, grounded theory methodology (Strauss & Corbin, 1998) was used to conceptualise effective mobility. Grounded theory is constructed from raw data through a process of constant comparison, thus methods and findings are combined in this report.

The term “effective” was carefully chosen through discussion between BVA team members. Possible seed questions for the study were then piloted with a convenience sample of colleagues and acquaintances (n=13). The research team considered that the term “functional” relates to what people can do, what works and what is useful, and this is preferable to the deficit thinking typically associated with “suffering vision loss.” However, functional performance might be achieved inefficiently or might be only partially effective. In relation to the bionic eye, the BVA research team wanted to consider and measure not just what people do, but what works really well and might constitute success.

First, the team undertook an enquiry with O&M specialists (n=15) to scope effective mobility, then used these ideas to shape a functional vison research protocol known as LoVADA – the Low Vision Assessment of Daily Activities. The LoVADA protocol was piloted with adults (n=40) who had advanced retinitis pigmentosa (<6/60 visual acuity or <10° visual fields). LoVADA will be described in detail elsewhere. In brief, the protocol includes three levels of route travel complexity, a visual integration task using guided travel, an orientation task involving free-roaming mobility, and a free-walking mobility task undertaken without a mobility aid which evaluates visual landmarking, straight line travel, and reorientation. These tasks generated multiple qualitative, quantitative, and graphic data streams, and included the semi-structured interview question: “What do you think makes your mobility effective?”

The draft categories that were derived from initial consultation with O&M specialists were then revised using qualitative data from the pilot LoVADA study. Two streams of qualitative data represented the perspectives of the research team as well as participants’ ideas about effective mobility.

This study was conducted with the approval of the Human Research Ethics Committee at the Royal Victorian Eye and Ear Hospital, Melbourne, and in accordance with the Declaration of Helsinki. Participants gave informed consent to their participation.

This study produced a new tool – the Effective Mobility Framework – through collaboration with international O&M specialists at an international conference and people with very low vision resulting from advanced retinitis pigmentosa. The Effective Mobility Framework includes the elements of Utility, Access, Orientation, Interdependence, Self-regulation, Efficiency, and Pleasure. This is a conceptual tool rather than a measurement instrument, which expands the dimensions of functional performance that might be considered and measured in O&M outcomes research, beyond what was previously captured by measuring speed and contacts in route travel tasks. The Framework informed the design of a centre-based functional vision research protocol, and has potential application to research which is designed to evaluate vision restoration treatments or O&M programs, whether in a centre-based setting or in participants’ more familiar life-space.

The breadth of the Effective Mobility Framework increases the chance of capturing data about the benefit of selected interventions, particularly when using embedded mixed methods (Creswell & Plano Clark, 2011) for data collection. However, the Framework also presents O&M researchers with some significant measurement challenges.

When investigating human performance, researchers’ observations of the participant and interpretation of participants’ comments are inevitably influenced by their own professional and cultural filters (Dillon, 1991). In qualitative research disciplines, researchers are encouraged to identify and bracket their own biases, then seek to be as transparent as possible about these influences when reporting findings (Curtin & Fossey, 2007). These interpretative processes mean that measurement of human performance can never be viewed as solely objective (Robson, 2011) and the selection of performance measures needs to be warranted with individual participants’ comments about their own O&M priorities. Thus, credible O&M outcomes research needs to generate both qualitative and quanititative data, and analyse the two data streams together so that measurement data about a client’s O&M outcomes can be considered meaningful to clients.

Measurement depends on there being stable, universally relevant constructs to measure. The paradox of this study is that in seeking to identify common elements of effective mobility, O&M specialists in the study emphasised the importance of respecting clients’ unique goals and priorities: “effective mobility is different at different life stages” and “different for every person.” For this reason, researchers investigating O&M outcomes would be misguided in seeking to develop a single “gold standard” research protocol. Functional performance in O&M essentially defies standardisation and the client needs to be responsive to the individual demands of his or her lived environment.

Researchers investigating O&M outcomes are thus faced with the reality that cohorts with common visual status and common O&M characteristics are likely to be quite small. Rather than an expectation of developing gold standard methods, a multiplicity of methods and measures is needed that can equip researchers and clients to capture whatever changes in O&M outcomes are relevant to an individual client. In this light, the Effective Mobility Framework should be regarded as a tool to facilitate more comprehensive research design and data generation, rather than a rigid research curriculum where every element must be measured with every person.

Researchers are encouraged to conduct a pilot enquiry with the target cohort to identify the elements of the Framework where benefits of the selected intervention seem most likely to be apparent before selecting or developing relevant measures. This approach is inverse to previous research that has built research tasks around the few existing measures. Interestingly, the only mention of speed in the study was from a client who identified the need to be adaptable to the context: “going slow and concentrating if less familiar; faster if I know the area or feel safe.”

The effective mobility concept map identified some constructs which are tangible and easy to measure. For example, it is obvious in the Utility category whether a person has arrived at the intended destination or achieved a chosen task. However, many tacit psychosocial elements, for example, resilience, pleasure, anxiety, or comfort call for further qualitative investigation before researchers can understand the best way to approach their measurement in the context of O&M action. Rather than leaving these difficult-to-measure elements out of the research design, the team recognised the value of capturing qualitative data about difficult constructs in the form of video, noted observations, a written record of clients’ self-talk, and contextual descriptions during O&M tasks, as well as more formal interview responses. These data enabled the team to further consider and develop measures that are meaningful to participants, not just to researchers.

Ordinal scales with clearly defined increments were trialled in the LoVADA protocol and showed some promise as a viable approach to measuring functional performance. These scales enabled multiple behaviours of functional interest to be incorporated into a measure, so that the integrated nature of functional performance could be captured holistically. For example, attempting to isolate and measure body positions, facial expressions, confidence, tension, social self-monitoring, and socially invasive behaviours was a daunting task, yet these constructs combined neatly into a posture/kinesics scale which eliminated the need for extensive description. Several performance scales were developed in collaboration with clients during the LoVADA study and as such capture constructivist data rather than the singular subjective opinion of self-report generated with Likert Scales. The value of each level on an ordinal scale is not consistent and Stevens (1946) who wrote the seminal paper on measurement scales noted that this inconsistency limits the statistical analyses which can be employed with ordinal data. The performance scales developed in the context of the LoVADA protocol will be reported in detail elsewhere.

The LoVADA pilot demonstrated the usefulness of the Effective Mobility Framework in directing the generation of rich data about O&M performance using standardised tasks in a centre-based context. However, the research team learned that data about O&M performance is not necessarily the same as data about O&M outcomes. Many of the LoVADA participants commented that they performed less effectively in the unfamiliar LoVADA venues than they would function in their familiar life-space, so findings from clinical trials are not necessarily transferrable to functional contexts. It remains to be seen whether the Effective Mobility Framework can be used to shape O&M outcomes research in the client’s life-space which better represents the clients’ everyday O&M experiences.

The Effective Mobility Framework has been informed by multiple perspectives including collaboration with international O&M specialists, input from LoVADA participants, and from the multidisciplinary BVA team which included optometrists, ophthalmologists, occupational therapists, and orthoptists, in addition to an O&M specialist. The categories identified in the Framework are sufficiently broad to accommodate variations in O&M cohorts or research contexts. However, the expert groups consulted were relatively small and much of the grounded theory analysis was undertaken by one person. There may yet be constructs which have not been included, and the domains in the Framework are likely to vary in importance from one client to the next. The Framework might need further amendment as a result of feedback from people who are blind, who have a greater degree of useful vision than the LoVADA participants, or whose vision issues are congenital rather than adventitious in origin.

Understanding the relationship between mobility, orientation, and vision continues to be challenging for researchers. Orientation became a category on its own in the Effective Mobility Framework, but vision did not. Mettler (2008) suggested that people who are fully sighted can be inclined to attribute greater importance to vision in relation to O&M than is necessarily warranted. However, none of the O&M specialists in the effective mobility forum mentioned vision. O&M specialists are used to working with people who have no vision, so this group of professionals likely regarded vision as optional rather than essential to effective mobility. This view is emphasised by O&M phenomenology (Berndtsson, 2009) and demonstrated in the practice of blind O&M specialists (Ferguson, 2007). Conversely, several clients in the LoVADA pilot emphasised the usefulness of their light perception only in effective mobility, suggesting that every little bit of vision is valuable. Considerably more research is needed to understand how best to measure the process of sensorimotor integration during O&M undertaken by people with very low vision.

The Effective Mobility Framework has already proven useful in supporting more comprehensive design of O&M outcomes research in the LoVADA protocol than has previously been reported, as well as prompting the development of new measures of functional performance. The Effective Mobility Framework also opens up new possibilities for structured research investigating activities and participation within participants’ more familiar life-space.