Influence of the built environment on community mobility of people living with visual disabilities: a scoping review

ABSTRACT

Understanding how the outdoor environment shapes the community mobility of people with visual disabilities is key to designing an accessible public realm and facilitating their rights to use outdoor spaces. A scoping review was conducted to explore 1) What aspects of the built environment affect the community mobility of persons with visual disabilities? and 2) How does the built environment affect the community mobility of persons with visual disabilities? Forty-three peer-reviewed publications from 2000 to 2022 were included after conducting database searches, screening of articles, and data charting. Studies focused on micro-environmental features related to sidewalks and crosswalks (e.g. landmarks, curbs, curb ramps, tactile warning/guiding surfaces, and accessible pedestrian signals), and broad environmental factors (e.g. neighbourhood amenities and street layout) and their influence on orientation, wayfinding, and safety. The paper discusses the role of the built environment in 1) posing barriers to outdoor mobility (e.g. potholes, poorly designed curb cuts, obstacles at waist-height or eye-level, poor lighting, inadequate pedestrian signal, complicated street layout), and 2) offering cues (e.g. visual, tactile, auditory, olfactory, kinaesthetic) for spatial perception and navigation. Focusing on how the built environment shapes community mobility is necessary to enhance accessibility through urban planning and design and assistive technology.

KEYWORDS:

• Community mobility
• built environment
• visual disabilities
• blind
• partially sighted
• scoping review

Introduction

Accessibility of the pedestrian environment is critical for the mobility of people with disabilities (Sitter & Mitchell, 2020; United Nations, 2006). The inaccessibility of roads, housing, public buildings and spaces for people with disabilities has prompted the focus on creating inclusive and accessible public spaces and transportation systems (United Nations, 2016). Navigating the pedestrian network involves two components: 1) wayfinding, i.e. ‘goal-directed movement using the cognitive process of identifying a route to reach a destination that is not within sight’ and 2) wayfaring, i.e. ‘embodied multisensorial experience that takes place during travel’ (Prescott et al., 2020, p. 647). Wayfinding requires knowledge of the topology of the sidewalks, crosswalks, and paths between two points. Wayfaring requires mobility skills and knowledge of conditions of the links in the pedestrian network such as slope, surface type, and width as well as safety features such as warning indicators and crosswalk beacons (Barczyszyn et al., 2018; Bolten et al., 2015; Brittell et al., 2017; Karimi et al., 2014; Kasemsuppakorn et al., 2015; Neis & Zielstra, 2014). However, there are personal (e.g. physical, psychological), environmental, and temporal challenges that make navigating the pedestrian environment difficult and dangerous for people with disabilities (Medola et al., 2014; Meyers et al., 2002; Rosenberg et al., 2013; Smith et al., 2016). The impact of mobility and navigation challenges on people with disabilities is also known to be felt through reduced community participation (Beale et al., 2006; Farr et al., 2012).

It is estimated that in 2020, there were 1.1 billion people living with vision loss worldwide, of whom 43 million are blind (The International Agency for the Prevention of Blindness, 2023). For people who are blind or have low vision, navigating the pedestrian environment can be particularly intimidating, especially in novel or constantly changing environments, primarily due to issues of spatial perception, cognition, decision-making and solving. People with visual disabilities perceive and understand the environment differently than sighted people, which in turn influences how they orient themselves and navigate to places. People with visual disabilities have to actively search for and follow cues to determine their location in the environment, identify a safe path of travel, and estimate distances between points along a route (Golledge et al., 1996). Knowledge of these cues, the information they provide and how they are spatially related to each other is acquired through exploration and repetition over time, and constitutes the person’s cognitive map of the environment, i.e. mental representations based on previous experience (Golledge et al., 1996). These maps are generally characterized by different sensory modalities, including auditory, haptic, kinesthetic, and olfactory, but in the case of blind people, particularly people with congenital blindness, physical space and objects are experienced and mentally represented through non-visual sensory modalities (Cattaneo et al., 2008). The amount of spatial information extracted through different sensory modalities varies, e.g. auditory and haptic perception enable people to acquire spatial information sequentially usually at the proximal scale, while visual perception allows for simultaneously acquiring different spatial information at small and large scales, which is why white cane users, for instance, can only acquire a limited amount of spatial information from every cane movement compared to sighted pedestrians (Schinazi et al., 2016).

Differences in the acquisition of spatial information through non-visual sensory modalities impose limits on the knowledge of locations, layouts, and routes for people with visual disabilities (Golledge, 1993). Integrating information from different parts of a walking route can be a difficult cognitive task, which is said to further limit route knowledge and layout comprehension for people with visual disabilities, underscoring the critical importance of route knowledge, including reference points and landmarks along the route that cue spatial decision-making (Golledge et al., 1996). The challenge of learning and remembering layouts and routes means people with visual disabilities favour taking familiar routes (Golledge et al., 1996). Routine is of the essence for safe outdoor mobility for people with visual disabilities, and straying from familiar routes and paths could lead to disorientation and induce fear of becoming lost in the outdoors (Golledge, 1993). While level differences and overhanging and protruding environmental features can be spotted visually and negotiated with relative ease by sighted people, these elements can seriously impact the safety of people with visual disabilities, especially when they are unanticipated and not part of one’s cognitive map.

Transportation planning research shows tensions between planning and design practice in relation to accessibility and the lived experience of people with disabilities, suggesting a lack of knowledge and awareness among built environment practitioners about how accessibility relates to the everyday realities of people with disabilities (Levine & Karner, 2023). Further, it has been suggested that a significant gap in planning research that contributes to inaccessibility is the lack of attention to diversity of disability (Levine & Karner, 2023). Part of addressing this gap involves examining planning and design implications for different subgroups of people with disabilities, including blind and partially sighted people. Exploring how people with visual disabilities interact with the built environment and identifying environmental barriers and facilitators is necessary to improve the accessibility of streets and outdoor spaces (Boys, 2014). Jeffries et al. (2020, p. 270) argue for ‘new ways of understanding place, diversity and inclusion’ and ‘a focus on plurality’ in urban design. This perspective aligns with understanding the mobility needs and challenges of diverse groups of users, and underscores the value of focusing on pedestrian issues experienced by people with visual disabilities. Parkin and Smithies (2012) emphasize the need for designers to know ways in which people with visual disabilities navigate the outdoor environment, noting the differences between how people with visual disabilities and designers view the public realm. Understanding how people with visual disabilities experience space can be a valuable asset to expand designers’ ways of thinking of the public realm (Heylighen & Herssens, 2014).

In this study, we focus on person–environment interactions in the context of outdoor mobility of people with visual disabilities and the ways in which the built environment shapes these interactions. While the body of literature on orientation and mobility of people with visual disabilities is extensive, to our knowledge, there have been no literature reviews that focus on the influence of the outdoor built environment on community mobility of people with visual disabilities. Hence, the aim of this study was to explore the scope and range of extant literature on the community mobility of persons with visual disabilities, focusing specifically on the influence of the outdoor built environment. The review was guided by the following questions: 1) What aspects of the built environment affect the community mobility of persons with visual disabilities? and 2) How does the built environment affect the community mobility of persons with visual disabilities?

Methods

To identify gaps in the current research, we conducted a scoping review. Our scoping review following the process outlined by Levac et al. (2010) for conducting scoping reviews. This framework follows and extends the methodological framework of Arksey and O’Malley (2005) enhancing rigor, reliability, and replicability. The framework includes six stages: 1) identifying the research question/s, 2) identifying relevant studies, 3) study selection, 4) charting the data, 5) collating, summarizing, and reporting results, 6) consultation (Levac et al., 2010). The study follows the reporting guidelines of the PRISMA Extension for Scoping Reviews (PRISMA-ScR) checklist (Tricco et al., 2018) (See Appendix 1 for PRISMA checklist). The academic research databases searched for related peer-reviewed journal articles, conference papers, and book chapters include GEOBASE, TRID, ASTI, PsycINFO, AgeLine, CINAHL, Medline, and Scopus. Keywords used for searches include: ‘vision loss’ OR ‘visual* impair*’ OR blind* OR ‘legally blind’ OR ‘low vision’) AND (environment* OR ‘pedestrian infrastructure’ OR neighbourhood OR neighborhood OR communit* OR ‘public space*’ OR ‘climate’ OR ‘weather’ OR natur* OR geograph* OR topograph*) AND (‘community participation’ OR ‘social participation’ OR ‘mobility’.

Articles included in the review, were selected based on the following criteria: 1) publication date range: 2000–2020, 2) study population: community-dwelling adults with visual disabilities, 3) study focus: the relationship between community-dwelling individuals with visual disabilities and the built environment (focus on outdoor mobility), 4) age of study participants: 18 years and above, 5) English language publications, and 6) place of publication: North America, Europe, Oceania. Follow-up searches were conducted for articles published between 2020 and 2022. Articles focusing on Deafblind participants were excluded.

Using Covidence, article titles and abstracts were independently screened by Research Assistants (RAs) using the keywords to identify a set of full-text articles for review based on the research focus. Three RAs screened the article title and abstracts and reviewed full-text articles. Article titles and abstracts or full-text articles that were not unanimously agreed upon were reviewed and resolved by the lead researcher. Data from eligible studies were collated and summarized in data table charts under the following categories: 1) goals/objectives, 2) research questions, 3) methods, including information about sample characteristics (e.g. older adults), sample size, methodology, 4) key findings. These data were analyzed using an inductive approach and general qualitative coding. A coding framework was developed based on codes assigned to the data charted from the first 10 studies by the three RAs. This coding framework was then applied to the remaining charted data by one of the RAs. The coded data were then consolidated under two broad themes, and narrative summaries were written for each of these themes to elucidate the role of the outdoor built environment in shaping community mobility of people with visual disabilities.

Results

As noted in Figure 1, initial database searches using the aforementioned keywords led to 6448 studies. Removal of duplicates and title-and-abstract screening brought this list down to 241 studies. Through the process of full-text screening, 183 studies were excluded, leaving 43 studies in the final review (Figure 1; see Appendix 1 for PRISMA checklist, and Appendix 2 for data chart). In terms of methods, 11 studies were based on quantitative methods, 28 were based on qualitative methods, and 4 employed mixed methods. In terms of geographic region, 21 studies were conducted in North America, 16 studies were from the Europe, 2 were from Australia, while 4 were from Oceania (New Zealand). While the studies reviewed did not have an explicit focus on policy or practice considerations for supporting the outdoor mobility of people with visual disabilities, some studies included evidence-based recommendations for policy and practice (Barlow et al., 2005; Due & Bierring Lange, 2018; Emerson & Sauerburger, 2008; Emma et al., 2007; Papadopoulos et al., 2020; Petraglia & Boudreau, 2006; Ratelle et al., 2010; Routhier et al., 2021; Williams et al., 2014)

Figure 1. Summary of study search results.

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While the review includes research comparing the pedestrian experience of people with visual disabilities and sighted participants (Guth et al., 2005), as well as studies with samples that included participants with different aetiologies of visual disabilities, there was little research examining the differences in mobility experience based on aetiology (e.g. between blind and partially sighted pedestrians) (Zimmermann-Janschitz et al., 2017). There were no studies that focused on the interplay of visual disability, physical, cognitive, or mental comorbidities, and built environmental factors in shaping the pedestrian experience. Further, the studies in our review did not examine patterns and differences based on gender, race, socioeconomic status, and other identity markers in relation to the role of the built environment in shaping the outdoor mobility of people with visual disabilities.

Most of the studies in the review were exploratory in nature and focus on identifying how different aspects of the built environment support or hinder the pedestrian experience for people with visual disabilities. The articles covered a broad range of mobility-related issues influenced by the built environment, including orientation and wayfinding, pedestrian safety, and interactions between the pedestrian, personal assistive devices, and built environmental features. In terms of aspects of the built environment that were covered in the studies reviewed, most of them focused on sidewalk- and crosswalk-related micro-environmental features that were framed as landmarks for people with visual disabilities (Cohen & Dalyot, 2021; Due & Bierring Lange, 2018; Fryer et al., 2013; Magnus, 2016; McGrath et al., 2017; Sakaja, 2020; Suderman & Redmond, 2015; Williams et al., 2014; Zimmermann-Janschitz et al., 2017). Features that were mentioned often include curbs, curb ramps, and tactile warning/guiding surfaces (Alexander et al., 2014; Cohen & Dalyot, 2021; Hwang, 2022; Nuzzi et al., 2018; Suderman & Redmond, 2015; Zhao et al., 2018), and accessible pedestrian signals (Barlow et al., 2005; Bentzen et al., 2000; Brown & Norgate, 2019; Cohen & Dalyot, 2021; Hwang, 2022). Studies also focused on the role of neighbourhood amenities (e.g. washrooms, transit stops) in shaping outdoor mobility (Cohen & Dalyot, 2021; Suderman & Redmond, 2015). Other studies looked at the mobility of people with visual disabilities in specific types of street layouts, e.g. Shared Spaces (Havik et al., 2012; Magnus, 2016), roundabouts (Cohen & Dalyot, 2021; Guth et al., 2005).

The following sections present key findings that highlight the role of the built environment in two broad areas: 1) Barriers to outdoor mobility, and 2) cues for spatial perception and navigation.

Barriers to outdoor mobility

Barriers reported in the studies reviewed broadly fell into the following six categories:

1. Sidewalk and ground surface quality issues that were found to hinder mobility include cracks, bumps, undulation, unevenness, potholes, and slipperiness (Brundle et al., 2015; Campisi et al., 2021; Jenkins et al., 2015; McMullan and Butler. 2019; Park et al., 2017; Zeng, 2015; Zhao et al., 2018). These surface issues were associated with depth perception problems and the risk of falling (Zhao et al., 2018, Jenkins et al., 2015).

2. Suboptimal-level changes (e.g. small or uneven curbs, minimal separation between adjacent curb ramps, unmarked stairs) (Brundle et al., 2015, Laliberte Rudman et al., 2016, Suderman & Redmond, 2015, Zeng, 2015). In one study, people with age-related macular degeneration found it harder to detect curbs and other drop-offs and obstacles at eye level within a safe distance, thus exacerbating the risk posed by these mobility hazards, while surface-level obstacles were detected more easily at a safe distance (Goodrich & Ludt, 2003). Level changes (e.g. displaced concrete slabs, steps) on the sidewalk, were found to be difficult to detect and need to be highlighted (e.g. with hazard signs or contrast warning) (Nuzzi et al., 2018, McMullan & Butler, 2019). These obstacles exacerbated the risk of falls and injury for people with visual disabilities (Jenkins et al., 2015, Laliberte Rudman et al., 2016). Studies found that people with visual disabilities are more likely to avoid walking in areas with such barriers that they perceive to be unsafe (Montarzino et al., 2007).

3. Waist height or eye-level objects (e.g. tree branches, open doors or windows, windowsills, shelves, railings) that are harder to detect (Magnus, 2016, Montarzino et al., 2007, Nuzzi et al., 2018, Williams et al., 2014, Zeng, 2015, Zhao et al., 2018, Zimmermann-Janschitz et al., 2017). Studies suggest that it is preferred when objects do not interfere with the path of travel and are located in the street furniture zone of the sidewalk (or in the case of overhead obstacles, to be placed at higher heights or within niches), so as to not disrupt wayfinding (Nuzzi et al., 2018, Ratelle et al., 2010, Suderman & Redmond, 2015).

4. Ambient conditions, such as poor lighting (Alexander et al., 2014, Kaminsky et al., 2014, Park et al., 2017) and inclement weather (e.g. snow and ice) (Laliberte Rudman et al., 2016, Magnus, 2016, Routhier et al., 2021, Suderman & Redmond, 2015) hindering the use of built environmental features (e.g. curbs and curb ramps, landmarks). Studies found inconsistent lighting resulted in shadows that exacerbated confusion, as well as challenged the identifiability and distinguishability of environmental features for people with low vision (Jenkins 2015). Bright sunlight was found to hamper the detection of level changes (Zhao et al., 2018).

5. Barriers at street crossing, such as lack of signal, defunct signal, or insufficient crossing time (Gallagher et al., 2011; McMullan and Butler, 2019; Park et al., 2017; Petraglia & Boudreau, 2006) and complex street intersection/crossing layouts (e.g. roundabouts do not afford clear sightlines for pedestrians and drivers and make pedestrian crossing difficult and unsafe) (Guth et al., 2005), and

6. Fixed (e.g. poles, signs, street furniture) and mobile/temporary obstructions (e.g. construction scaffolding, cones, and closures, restaurant furniture, sandwich boards on sidewalk, vehicles, bicycles) (Brundle et al., 2015, Magnus, 2016, Park et al., 2017, Zimmermann-Janschitz et al., 2017). It is suggested that mobile obstacles are harder to locate and remember than fixed obstacles, while temporary obstructions such as sidewalk closures prompt people with visual disabilities to cross the street unexpectedly, leading to confusion and disorientation (Zimmermann-Janschitz et al., 2017).

Studies suggest that objects in the streetscape can sometimes play the dual role of barrier and landmark for blind pedestrians while walking outside (Sakaja, 2020). Research suggests that walking paths that are completely devoid of obstacles and are clear, wide, and open throughout make it difficult to navigate and maintain a straight path of travel due to the lack of boundaries and clues, causing blind pedestrians to lose their direction (Sakaja, 2020; Williams et al., 2014). Hitting objects with a white cane and receiving tactile feedback from the built environment is important to find one’s way around the outdoors (Williams et al., 2014).

Cues for spatial perception and navigation

The literature suggests that people with visual disabilities receive cues from different elements of the built environment that in turn prompt decision-making for outdoor mobility and navigation. These are detailed under the following subheadings:

Tactile cues

Blind and partially sighted people identified landmarks that provide multimodal information, i.e. through the different senses (Fryer et al., 2013). These studies indicated that blind pedestrians found haptic feedback received through vibration, friction, and acoustics (often using a white cane) from tactile cues to be most useful for outdoor mobility (Due & Bierring Lange, 2018; Jenkins et al., 2015; Landry et al., 2010; Lauria, 2017; Papadopoulos et al., 2020). Tactile cues originate from two sources: 1) naturally occurring or pre-existing elements in the streetscape, such as landscaping along the sidewalk or material found along the edge of buildings (Cohen & Dalyot, 2021; Koutsoklenis & Papadopoulos, 2014; Suderman & Redmond, 2015), and 2) purpose-built infrastructure to support navigation for people with visual disabilities (e.g. tactile warning surface on curb ramps and guiding surface on sidewalks). The latter group of tactile cues are most useful for navigation at street crossings (e.g. cues that indicate where the sidewalk meets the road, which way to cross the street, and when to cross), which in turn has important implications for pedestrian safety (Cohen & Dalyot, 2021; Routhier et al., 2021; Williams et al., 2014).

One of the key prerequisites for tactile cues to be used in mobility and navigation decisions is their detectability, which in turn is contingent on sufficient textural/tactile contrast between the environmental feature and its surrounding surfaces (Routhier et al., 2021). Partially sighted people may be able to additionally detect tactile cues with the help of visual contrast between the environmental feature and its surrounding area, which may be compromised due to the presence of snow, moisture, or poor lighting at night (Routhier et al., 2021). Negative characteristics associated with tactile cues include potential slipperiness of material when wet, poor textural contrast, and parts of the tactile features (e.g. bumps) that cause white canes to get stuck (Emma et al., 2007; Routhier et al., 2021). Studies also point to the importance of precise placement and location of tailor-made tactile cues. For instance, textural markings and placement of tactile surfaces on curb ramps should be aligned with the crosswalk, to guide people with visual disabilities effectively and safely along a straight path across the street (Nuzzi et al., 2018; Routhier et al., 2021; Suderman & Redmond, 2015).

Kinesthetic cues

People with visual disabilities are also known to utilize kinesthetic cues, such as change in elevation or slope to guide their path of travel (Suderman & Redmond, 2015). This provides crucial information, for instance, at the street crossing, where a change in slope cues people to their arrival at the intersection and signals the presence of the curb ramp (Suderman & Redmond, 2015). A lack of tactile and kinesthetic cues (i.e. absence of curbs, demarcation between road/bike path and pedestrian path) as seen in streets designed with the ‘Shared Space’ approach can be disorienting, challenging the ability to perceive distinction between pedestrian zone and road and resulting in unsafe situations (Havik et al., 2012; Magnus, 2016).

Auditory cues

Another set of studies focused on the role of auditory cues in supporting the outdoor mobility and navigation of people with visual disabilities. Accessible pedestrian signals (i.e. signals that provide visual, auditory, and vibrotactile cues to inform people with disabilities when to cross the street) are crucial sources of support that help people with visual disabilities know when to start crossing the street and determine the direction of crossing (McGrath et al., 2017; Petraglia & Boudreau, 2006) making outdoor travel easier and safer (Cohen & Dalyot, 2021). In the absence of accessible pedestrian signals, people with visual disabilities are not able to easily/effectively determine when cars stop, when they can start crossing, and when they have finished crossing (Brown & Norgate, 2019). However, studies also point to issues with auditory prompts provided by pedestrian signals: 1) presence of surplus auditory cues (e.g. for different crosswalks at the intersection) making it difficult to follow the correct cue, 2) low audibility of signal and noise from surroundings (e.g. traffic, pedestrians) make it difficult to hear the cues, and 3) excessively loud pedestrian signals drown out other important environmental sounds (e.g. sounds of traffic flow that are key for safe crossing) (Jenkins et al., 2015; Magnus, 2016; Montarzino et al., 2007; Nuzzi et al., 2018; Petraglia & Boudreau, 2006). Audio cues were also found to be used by people with visual disabilities to identify the location of certain destinations (e.g. certain sounds associated with the location of local park) (Papadopoulos et al., 2020). Large objects (e.g. bus shelters) alter the movement of air and reflect ambient noise, making them landmarks that provide indirect acoustic cues (Suderman & Redmond, 2015). Auditory cues that provide orientation and wayfinding information are also found in distinctive sounds made by the white cane touching different building façade materials (e.g. wood, glass) (Due & Bierring Lange, 2018).

Visual cues

Some studies suggest that visual cues are useful for the outdoor mobility of partially sighted people, e.g. visual contrast between different environmental features and the balance of light and shade are helpful to detect level changes, such as curbs and stairs, and avoid tripping and falling (Zhao et al., 2018). Depending on ambient light, visual contrast can also be useful for partially sighted people to distinguish between different materials (e.g. grass and concrete) and clearly locate the walking path (Suderman & Redmond, 2015; Williams et al., 2014). Partially sighted people are also found to keep track of the number of environmental features (e.g. stairs, doors, and entrances) encountered en route, as well as changes in the built environment (e.g. construction, closing or changing locations of businesses) to keep their cognitive maps of the environment up-to-date and aid in wayfinding (Williams et al., 2014; Zimmermann-Janschitz et al., 2017).

Some studies also found olfactory cues to be useful markers of locations of different community destinations (e.g. bakeries, restaurants) (Papadopoulos et al., 2020; Sakaja, 2020). These cues were found to be highly preferred along with auditory and haptic cues by blind people (Papadopoulos et al., 2020). There were a few studies that sought to evaluate specific safety and navigation features (Emma et al., 2007; Landry et al., 2010) and accessibility and safety implications of implementing the Shared Space approach (i.e. a design philosophy aimed to create more pedestrian-oriented streets that induce behavioural change in vehicle users by facilitating better social cues and interactions between pedestrians and vehicle users) implemented in urban design (Havik et al., 2012). Future studies should further the focus on evaluating the different elements of the built environment identified in this review, in terms of how well they support the outdoor mobility of people with visual disabilities. For instance, studies could evaluate different mobility, orientation and wayfinding, and safety features in the built environment, particularly, their usefulness before and after redevelopment, as well as how their supportiveness varies depending on geographical context (e.g. between urban, suburban, and rural areas, between neighbourhoods with differing levels of resources or socioeconomic status).

Discussion

This paper focuses on reviewing and integrating findings from the sizeable body of knowledge on the importance of the built environment for the outdoor mobility of pedestrians with visual disabilities. While the literature related to this topic has been reviewed as part of a broader focus on different groups of people with disabilities (Prescott et al., 2020; Stoker et al., 2015), an in-depth literature review of how the built environment shapes the pedestrian experience for people with visual disabilities has not been done to date. We hope that this paper will be a useful addition to the body of knowledge on this topic and serve as a guide for future research on this topic and in related areas.

The studies reviewed heavily emphasized the cueing properties of different environmental features. In particular, tactile cues in the outdoor environment were highlighted, as being important sources of spatial information for people with visual disabilities. The attention to this environmental feature in the literature underscores the role of tactile/haptic cueing for blind people to comprehend spatial information and patterns (Golledge, 1993). The literature also indicated the value of combining different sensorial cues within environmental features, e.g. tactile warning surfaces that provide both textural and visual contrast. The importance of cueing through multiple sensory modalities and designing for redundancy in spatial information is a key accessibility consideration ensuring that people with visual disabilities are adequately supported in detecting different environmental features (Schinazi et al., 2016). Research suggests that people with visual disabilities require spatial information at different levels to aid wayfinding (Golledge et al., 1996). At the proximal level, this involves counting, locating, and identifying micro-environmental features, keeping track of series and sequences of cues, and discerning and avoiding obstacles (Golledge et al., 1996). At the larger geographical scale, this entails knowing the location of near and distant buildings, local terrain and shifts in terrain, and understanding the street layout (Golledge et al., 1996). The studies reviewed focused more on proximal environmental features (e.g. obstacles and barriers in the path of travel, micro-environmental features located near the walking route that serve as audio/tactile/visual cues) that shaped pedestrian experience, with little attention to larger-scale elements that shape mental representations of the outdoor environment (e.g. buildings that serve as landmarks, construction sites that create route disruptions). Future research should seek to expand the focus on different levels of spatial information to get a fuller understanding of the cognitive maps of people with visual disabilities and explore ways in which planning and design can support outdoor mobility for this population through accommodations and modifications at different spatial levels.

Our study indicated little attention to differences in mobility experience based on aetiology. Visual disabilities encompass a wide spectrum of spatial access needs and need to be better accounted for in future research on this topic. Previous studies have shown that blind people use tactile and auditory cues more extensively than people with visual impairment in comprehending spatial information and patterns (Cattaneo et al., 2008). Bredmose et al. (2023) identify differences in urban design elements that are supportive of people with visual impairment (e.g. colour contrast on the edge of steps, visual delineation of walkways and bike lanes) and those that are useful for blind people (e.g. tactile walking surface indicators, tactile delineation between walkway and bike lanes, audible beacon pedestrian signal at crossing). The studies reviewed did not examine differences in the influence of the built environment on the outdoor mobility of people with visual disabilities based on gender, race, socioeconomic status, or other identity markers. Navigation support for people with visual disabilities should consider population-level needs, as well as acknowledge and accommodate individual differences that set people apart from one another in the ways that they interact with the outdoor environment (Schinazi et al., 2016). We believe that adopting an intersectional lens (i.e. how multiple systems of oppression shape the experience of people with disabilities based on different identity markers) (Brinkman et al., 2023) in future studies would not only help generate more nuanced understandings of the mobility experiences of people with visual disabilities but also inform equitable decision-making and planning that caters to disproportionate barriers experienced by minoritized groups of people with visual disabilities.

While it is important to understand that the built environment is but one component in this complex web of person–environment dynamics, it is also important to break down what exactly constitutes the facilitative and hindering characteristics of the built environment and articulate its role in shaping mobility in terms of concrete, measurable attributes. This scoping review is an attempt towards identifying those specific aspects and features of the built environment that are salient for the outdoor mobility of people with visual disabilities. Using this knowledge as our foundation, we are in the process of developing tools to help conduct environment accessibility audits from the perspective of people living with visual disabilities, so as to better evaluate how far the outdoor environment in neighbourhoods is supportive of the access needs and requirements of this population.

Limitations

While our review focuses mainly on the role of the built environment on the outdoor mobility of people with visual disabilities, it is important to view this in the context of other factors. For example, how people use and interact with the various elements of the built environment that have been found to be important for their outdoor mobility will vary in accordance with a host of personal, social, and temporal factors (e.g. aetiology of visual disability, interpersonal dynamics with other pedestrians and road users, the types of activity in the surroundings, weather conditions). For example, how does personal assistance mediate the interactions and relationship between the outdoor built environment and people with visual disabilities? Assisted travel lessens the onus on people with visual disabilities to perform spatial tasks such as obstacle recognition and avoidance or making route decisions at choice points, when compared to people traveling alone (Golledge et al., 1996). In the studies reviewed, one study (Williams et al., 2014) compared the environmental features that were used as navigation cues by people with visual disabilities and the environmental features referenced in verbal navigation prompts provided to the people with visual disabilities by sighted walking companions, pointing to significant differences in comprehension of outdoor spatial information and patterns by the two groups of people. While this aspect of the study was not the focus of our review, this is just one example of the myriad of factors that are a part of the everyday pedestrian experiences of people with visual disabilities and informing how the built environment is negotiated and navigated.

We also acknowledge that the studies included in this review offer perspectives that are limited to North America, Europe, and Oceania that may or may not be transferable to other global contexts. Examining studies conducted in other parts of the world is necessary to generate more diverse and context-specific perspectives on how the built environment impacts outdoor mobility for this population and should be given due consideration in future research.

Research implications

Understanding how the outdoor built environment influences the outdoor mobility of people with disabilities has implications for enhancing access and inclusion in cities through design and planning, given knowledge gaps among built environment practitioners regarding the accessibility needs of people with disabilities (Jackson, 2018). Access work in planning and design that is sensitive to the lived experience of people with visual disabilities should go beyond compliance with accessibility standards and regulations and aim for solutions that reflect what people actually need and require from the built environment for outdoor activity and participation, rather than assumptions of people’s access needs and requirements (Jackson, 2018; Jackson & Everett, 2019; Hallgrimsdottir et al., 2016; Levine & Karner, 2023). Accessibility for people with visual disabilities should not be limited to installing tactile warning and guiding surfaces at street intersections but should account for the wide range of complex spatial decisions required for the entire pedestrian journey. Accessibility considerations for people with visual disabilities should also include measures such as creating a clear path of travel on sidewalks, visual and tactile demarcation around obstacles on the sidewalk, installation of accessible pedestrian signals with auditory and visual cues, and alignment of curb cuts, all of which have relevance for the access needs of other groups of people with disabilities, as well as non-disabled people (Smithies, 2015; Parkin and Smithies, 2012). Seeking the expertise of people with visual disabilities in the research and development of solutions to outdoor mobility challenges should be seen as an important priority in planning and design (Emma et al., 2007).

Technological advancements are starting to change the way we understand navigation for people with visual disabilities (Smithies, 2015). Assistive technology can potentially support in all stages of the pedestrian journey, from providing relevant context-specific spatial information ahead of the journey, to assisting with journey planning and optimal route selection to destination, to enabling sensing one’s immediate surroundings and supporting real-time navigation (e.g., avoiding obstacles, crossing streets) to get to the desired destination (El-Taher et al., 2021; Fernandes et al., 2019). Research suggests the need for datasets to be built identifying different obstacles and accessibility information that can inform the work of navigation technological systems at each stage of the pedestrian journey (El-Taher et al., 2021). Our study offers useful perspectives to help initiate this endeavour, underscoring the value of translating knowledge of important built environmental features for the design of navigation technology (Due & Bierring Lange, 2018; Williams et al., 2014). Future research on this topic should seek to build an evidence base for these technological systems that accurately reflects the actual access needs and requirements of people with visual disabilities (Kuriakose, Shrestha, & Sandnes, 2022).

Conclusion

Our review suggests that the built environment shapes the outdoor mobility of people with visual disabilities in a variety of ways and in turn serves to maintain their sense of independence and safety, both of which are important values and priorities associated with walking outside for this population. Understanding how the built environment impacts outdoor mobility through the lens of visual disabilities is important to honour and realize people’s rights to have free access to outdoor spaces and foster inclusivity in our communities. The focus on supporting the outdoor mobility of people with visual disabilities through the enhancement of the built environment aligns with Article 9 of the Convention on the Rights of Persons with Disabilities (CRPD) (United Nations, 2006). The findings from this scoping review are expected to guide researchers and practitioners in furthering their efforts towards the creation of more accessible pedestrian environments for people with visual disabilities.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study has been conducted in the SWAN (Stakeholders’ walkability/wheelability audit in neighbourhoods) project, which is part of the larger project Mobility, Accessibility and Participation (MAP) among people with disabilities, which is funded by the Social Sciences and Humanities Research Council (SSHRC).

Appendix 1

PRISMA Systematic Review Checklist

Table

Item		Explanation	Page number
Abstract	2	See the PRISMA 2020 for Abstracts checklist.
INTRODUCTION
Rationale	3	Describe the rationale for the review in the context of existing knowledge.	3
Objectives	4	Provide an explicit statement of the objective(s) or question(s) the review addresses.	4
METHODS
Eligibility criteria	5	Specify the inclusion and exclusion criteria for the review and how studies were grouped for the syntheses.	5
Information sources	6	Specify all databases, registers, websites, organisations, reference lists and other sources searched or consulted to identify studies. Specify the date when each source was last searched or consulted.	4
Search strategy	7	Present the full search strategies for all databases, registers and websites, including any filters and limits used.	5
Selection process	8	Specify the methods used to decide whether a study met the inclusion criteria of the review, including how many reviewers screened each record and each report retrieved, whether they worked independently, and if applicable, details of automation tools used in the process.	5
Data collection process	9	Specify the methods used to collect data from reports, including how many reviewers collected data from each report, whether they worked independently, any processes for obtaining or confirming data from study investigators, and if applicable, details of automation tools used in the process.	5
Data items	10a	List and define all outcomes for which data were sought. Specify whether all results that were compatible with each outcome domain in each study were sought (e.g. for all measures, time points, analyses), and if not, the methods used to decide which results to collect.	Not Applicable
	10b	List and define all other variables for which data were sought (e.g. participant and intervention characteristics, funding sources). Describe any assumptions made about any missing or unclear information.	Not Applicable
Study risk of bias assessment	11	Specify the methods used to assess risk of bias in the included studies, including details of the tool(s) used, how many reviewers assessed each study and whether they worked independently, and if applicable, details of automation tools used in the process.	5
Effect measures	12	Specify for each outcome the effect measure(s) (e.g. risk ratio, mean difference) used in the synthesis or presentation of results.	Not Applicable
Synthesis methods	13a	Describe the processes used to decide which studies were eligible for each synthesis (e.g. tabulating the study intervention characteristics and comparing against the planned groups for each synthesis (item #5)).	5
	13b	Describe any methods required to prepare the data for presentation or synthesis, such as handling of missing summary statistics, or data conversions.	5
	13c	Describe any methods used to tabulate or visually display results of individual studies and syntheses.	5
	13d	Describe any methods used to synthesize results and provide a rationale for the choice(s). If meta-analysis was performed, describe the model(s), method(s) to identify the presence and extent of statistical heterogeneity, and software package(s) used.	5
	13e	Describe any methods used to explore possible causes of heterogeneity among study results (e.g. subgroup analysis, meta-regression).	Not Applicable
	13f	Describe any sensitivity analyses conducted to assess robustness of the synthesized results.	Not Applicable
Reporting bias assessment	14	Describe any methods used to assess risk of bias due to missing results in a synthesis (arising from reporting biases).	Not Applicable
Certainty assessment	15	Describe any methods used to assess certainty (or confidence) in the body of evidence for an outcome.	Not Applicable
RESULTS
Study selection	16a	Describe the results of the search and selection process, from the number of records identified in the search to the number of studies included in the review, ideally using a flow diagram.	5
	16b	Cite studies that might appear to meet the inclusion criteria, but which were excluded, and explain why they were excluded.	Not Applicable
Study characteristics	17	Cite each included study and present its characteristics.	Presented in data chart
Risk of bias in studies	18	Present assessments of risk of bias for each included study.	Not Applicable
Results of individual studies	19	For all outcomes, present, for each study: (a) summary statistics for each group (where appropriate) and (b) an effect estimate and its precision (e.g. confidence/credible interval), ideally using structured tables or plots.	Not Applicable
Results of syntheses	20a	For each synthesis, briefly summarise the characteristics and risk of bias among contributing studies.	Not Applicable
	20b	Present results of all statistical syntheses conducted. If meta-analysis was done, present for each the summary estimate and its precision (e.g. confidence/credible interval) and measures of statistical heterogeneity. If comparing groups, describe the direction of the effect.	Not Applicable
	20c	Present results of all investigations of possible causes of heterogeneity among study results.	Not Applicable
	20d	Present results of all sensitivity analyses conducted to assess the robustness of the synthesized results.	Not Applicable
Reporting biases	21	Present assessments of risk of bias due to missing results (arising from reporting biases) for each synthesis assessed.	Not Applicable
Certainty of evidence	22	Present assessments of certainty (or confidence) in the body of evidence for each outcome assessed.	Not Applicable
DISCUSSION
Discussion	23a	Provide a general interpretation of the results in the context of other evidence.	6
	23b	Discuss any limitations of the evidence included in the review.	14
	23c	Discuss any limitations of the review processes used.
	23d	Discuss implications of the results for practice, policy, and future research.	15
OTHER INFORMATION
Registration and protocol	24a	Provide registration information for the review, including register name and registration number, or state that the review was not registered.	The review was not registered
	24b	Indicate where the review protocol can be accessed, or state that a protocol was not prepared.	Not Applicable
	24c	Describe and explain any amendments to information provided at registration or in the protocol.	Not Applicable
Support	25	Describe sources of financial or non-financial support for the review, and the role of the funders or sponsors in the review.	16
Competing interests	26	Declare any competing interests of review authors.	16
Availability of data, code and other materials	27	Report which of the following are publicly available and where they can be found: template data collection forms; data extracted from included studies; data used for all analyses; analytic code; any other materials used in the review.	Data chart is provided in a separate file

From: Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ 2021;372:n71. doi: 10.1136/bmj.n71

For more information, visit: http://www.prisma-statement.org/

Appendix 2:

Data Chart

Table

#	Lead author & Publication year	Aim	Population & sample characteristics	Research design & methods	Key substantive or theoretical findings
1	Alexander et al. (2014)	To determine how age-related macular degeneration (AMD) and changes in ambient light affect the ability to negotiate a curb while walking.	Study location: Canada. 10 older adults with AMD (OAMD) and 11 normal-sighted controls.	Quantitative study. Curb negotiation task under normal light, dim light and following a sudden reduction. Questionnaire on perceived effects of lighting on daily living activities.	Participants (OAMD) 1) walked slower in curb ascent but attenuating to light reduction slowed both those with AMD and control, 2) took longer to initiate movement than control in sudden reduction of light conditions., 3) moved using shuffling (cautious walking) during the sudden reduction of light condition. Descent was harder than ascent, particularly for those with AMD who stepped more cautiously, 4) reported greater perceived impairment in navigating daily living activities due to lighting (lower means more impairment) than control group. Those with more perceived impairment had slower gait speed in poorer lighting.
2		To examine the practices used by persons with visual disabilities to learn about their environments and related challenges.	Study location: U.S.A. 9 participants including 4 females and 5 males with visual disabilities for high level learning study. 8 participants including 6 females and 2 males with visual disabilities for point of interest study which emerged from gaps in the prior study.	Qualitative study. First study: semi-structured interviews with observations of exploration strategies in two unfamiliar outdoor spaces. Complemented with focus groups with six O&M experts. Second study: was task based-frequent environment knowledge task and frequent environment exploration task.	First study: Participants took time, build their cognitive map using different information sources. Strategies used include: calling ahead, conversations with sighted friends, internet resources, walking tours, personal navigation guides and cues. Navigation is pragmatic focusing on landmarks and relationships that define a path from one place to another. This includes environmental cues that help solidify relationships between directions and landmarks. Spatial learning was facilitated by four factors, namely: O&M proficiency, navigation aides, changes in the environment and environmental familiarity. Second study: Participants learned to integrate existing places into their cognitive maps slowly. Cognitive maps were created based on participants’ preference for comfort and familiarity and the type of environment. Content-rich environments were preferred. Loyalty to certain brands, emotion ties and good historical knowledge of landmarks helped create preferences. Additional information requirements included accessibility, safety, and business hours.
3	Barlow et al. (2005)	To provide a descriptive analysis of broad measures of safety, orientation, and the need for assistance or intervention for safety in crossing, and implications for O&M instruction.	Study location: U.S.A. 48 participants including 30 men and 18 women aged 20–78, the majority using a long cane or a guide dog.	Qualitative study. Participants were tested and traveled two unfamiliar routes at each of two intersections	Regarding ‘safety’, participants are at risk if they complete crossings after traffic has received a green signal. The longer the delay, the more likely they are to be on the street after the onset of traffic- for all three cities. At crossings where push button activation was required, small number of participants could looked for, found, and pushed the button. In comparison to the crossings where there is enough time to cross and no button, very few participants were able to begin crossing during the walk interval at pedestrian-activated crossings. Regarding ‘orientation’, most crossings began with appropriate alignment and location but 50% ended up outside the crosswalk. Regarding ‘independence’, the majority of decisions were made independently but assistance was requested (53%) for the starting location, 60% for alignment and 73% for determining when to start crossing.
4	Bentzen et al. (2000)	To provide more information than anecdotal on the difficulties pedestrians with visual disabilities experience at signalized intersections.	Study location: U.S.A. 356 Orientation and Mobility (O&M) instructors.	Quantitative study. A survey to obtain information on the difficulties orientation and mobility specialists had observed to be experienced by blind pedestrians at signalized intersections and the causes of difficulties that they considered to be the most important.	About ‘knowing when to begin crossing’, 98% reported difficulties. Causes of difficulties: traffic being intermittent, right turning traffic masking the surge of parallel traffic, too noisy intersection, too far surge of traffic. Regarding ‘crossing straight across the street’, 97% reported difficulties aligning to cross the street. Causes of difficulty: intermittent or sporadic traffic based on time of day/week, offset intersection, no acoustic guideline indicating direction.Regarding ‘Use of pushbuttons’, 94% reported difficulties. Causes of difficulty: couldn’t recognize if they needed to push a button, locating the pushbutton, couldn’t recognize the actuated crosswalk, too far push button. Regarding ‘Use of audible pedestrian signals’, 60% reported difficulties. Causes of difficulty: couldn’t recognize which crosswalk had the walk signal, too quiet or loud signal, couldn’t remember which sound was associated with which crossing, couldn’t localize the sound of an APS, were confused by the sound of an APS for another intersection, confused the signal with a bird sound and vice versa.
5	Brown and Norgate (2019)	To what extent do blind or partially sighted pedestrians perceive (understand in real-time, the perceptions/thoughts/emotions) barriers or facilitators when moving through a shared space.	Study location: UK. 5 participants including 3 totally blind and 2 partially sighted aged 21–54. 3 used a cane, 1 used a guide dog, 1 used a GPS; all had been trained to use their devices.	Qualitative study. 5 case studies involving blind or partially sighted adult pedestrians who walked a designated route through an urban shared space	‘Crossing barriers’ found include: being unaware of informal crossings, unsure if cars are stopping for them, unable to perceive the distance to the other side of the road, unsure when they’ve finished crossing, needing support to cross. Difficulties experienced in ‘distinguishing the road and space to walk’ due to lack of perceived demarcations. To assess the demarcations, canes must go into the road which risks it getting run over. ‘Street furniture’ act as barriers (e.g. veer participants toward the road) but also act as facilitators (e.g. lamp posts help view road boundaries). Participants showed negative reactions, feeling unsafe and scared of wandering into traffic.
6	Brundle et al. (2015)	To explore causes of falls from the perspective of older adults with visual disabilities.	Study location: UK. 54 individuals with visual disabilities.	Qualitative design. Phase 1. 4 focus group and 6 interviews, phase2: 33 interviews.	Participants attributed fall in out-of-home environment to pavements and steps, ramps as hazards, left out dustbins, shop signs, products and hedges. Slipping due to moss, gravel, wet leaves and litter.
7	Campisi et al. (2021)	To evaluate the walkability of urban environments for individuals with visual disabilities based on the Commented Paths Method (CPM).	Study location: Italy. 79 blind and partially sighted persons participated in phase 1. A sub-sample of 21 individuals participated in phase 2 and 3.	Qualitative Study. 1. Survey, 2. Subjective evaluation, 3. Walkability Assessment based on perceptions and feelings.	Analysis revealed a difficulty in movement above all due to the presence of obstacles. The most influencing factors were represented by the surface level variation and its maintenance conditions. The knowledge of the area facilitated the walk generally. But the absence of certain reference points and the correct positioning of urban furniture have created real architectural barriers. Overall, the participants were characterized by negative feelings and emotions, showing negative peaks at the most discontinuous elements (i.e. stairs) or large spaces with uneven characteristics (i.e. the square).
8	Cohen and Dalyot (2021)	To define and categorize spatial criteria for mobility, accessibility, and safety of blind pedestrians.	Study locations: Israel & U.S.A. Interview session one– 1 rehab services manager. Interview session two– 5 Blind people plus 10 O&M instructors Observation session three– 2 Blind people plus 1 O&MI instructor. Interview and observation session four– 6 Blind people. Interview and observation session five– 3 Blind people. Interview and observation session six – OM instructor	Qualitative study design. Series of 1) user-centred, open-ended interviews, and 2) observations of blind participants navigating in urban environment	Linear routes preferred near a road with distinct curb (or other edge definition). Non-linear paths as in roundabouts and paths in parks are difficult to navigate. Complex routes with turns are not preferred. However, participants with guide dogs experience fewer challenges following such routes than people with canes. Shorter routes, where possible are preferred by blind people. Permanent landmarks (e.g. restaurants, traffic lights, trees, bus stops) are meaningful for wayfinding assistance. Street crossing features conveying info in non-visual format about intervals of when to (not) walk are important for participants. Tactile surfaces and accessible pedestrian signals are helpful cues, but participants also manage without them. Uncontrolled crossings are mostly avoided by participants, instead, ones with signals are preferred and considered safer, even if it means walking further to get to them. Intersections with greater number of roads are too complex and not recommended. T-junctions are preferred as they let participants to pay attention to traffic in all directions. Sounds of oncoming traffic on the road convey the direction of moving cars, which serves as a useful orientation cue. Public squares hinder wayfinding as they are often crowded and busy. Intersections with obstacles that prevent drivers from seeing blind pedestrians compromise the latter’s safety.
9	De Winne (2006)	To provide design criteria and recommendations for accessible public spaces	Study location: Belgium	Recommendation and guidelines article)	Designers should be attentive of guidelines, warning markings only at dangerous crossings as square ground crossings, involve colour contrast and rubber paving.
10	Due and Bierring Lange (2018)	The study is on how a blind person goes from A to B and how burden of interactional work involved in avoidance falls on the non-blind pedestrian (Moses effect = pedestrians moving aside for the blind person)	Study location: Denmark. 1 blind person (male; age not specified)	Qualitative study. Video recording of participant’s routine outdoor walks	Participant receives tactile information through the cane while crossing streets (e.g. zebra crossings are elevated strips). Traversing large open spaces can be challenging and cause veering from intended path, especially in case of a lack of tactile features. Shop façade is used by participant as a navigational touch point (a kind of landmark) for orientation and restructuring the straight path of travel after crossing large open space. Cane used to move along the façade and identify its edge (window frame). Raised curb serves as a touch point and identified using the cane. Distinctive sounds of the cane touching wood or glass helps the participant confirm their location and recognize the landmark. When accompanied by guide dog, temporary obstructions in the participant’s path of travel are sensed by the dog and the dog changes the participant’s trajectory and guide them back on track again. In some cases, the guide dog adjusts its position so that the participant can walk on the tactile guidance line.
11	Emma et al. (2007)	To identify structures for guidance surfaces and stop warning surfaces that help blind people who use long white canes to navigate and orient themselves.	Study location: Sweden. Phase 1: 14 blind participants. Phase 2: 8 blind participants	Qualitative study. Phase 1: identifying structures and stop surfaces helping with navigation and orientation using person observation, interviews and video filming. Phase 2: evaluating surfaces that turned out in step 1 to be usable in real traffic settings using test person observation, tape recording, interviews, and an assessment of the functional limitations of the test persons according to housing enabler.	Phase 1: Participants had great difficulty in feeling the difference between guidance surfaces and warning surfaces and a majority didn’t notice the transitions unless it was smooth surface (flat topped rather than rounded dome blisters were better). The canes got stuck on some flat bevel surfaces and guidance surfaces with ribs stopped the cane as well. Smooth bordering surfaces make it easier to feel differences and follow the route. Phase 2: all slab surfaces were able to be detected, with Swedish participants rating theirs as easiest with the Japanese following, English, then Danish. One point on the route however nearly everyone failed to identify it due to the natural guideline before warning surface.
12	Emerson and Sauerburger (2008)	To assess the ability of people with visual disabilities to reliably detect oncoming traffic at crossing situations with no traffic control.	Study location: U.S.A. 17 women and 6 men with visual disabilities aged 24–67; 9 had congenital vision loss and 13 lost their vision at age 3+ and have normal hearing.	Qualitative study. Blindfolded participants sat at the road side and indicated when they first hear a vehicle from the left or right at 3 residential sites of average residential sound dB. Data was videotaped, a sound-level meter ran continuously. Participants were exposed to 6 scenarios: straight road & no obstacles, straight road & sound obstruction, severe road bend, minor road bend, hill facing afar, heavily treed approach	Straight and no obstacles’ scenario had no detections under 7s and the severe bend and hill had the lowest average detection times. Half the safety margins in the severe bend condition were 0 (not able to cross on time). In the ‘minor bend’ and ‘treed’ scenarios, safety margins decreased with increases in ambient sound. Detection at the ‘severe bend’ and ‘hill’ scenarios degraded at lower sound levels than the straight. Straight road detection times decreased as ambient sound increased. Ambient sound level was the strongest predictor of detection time followed by environmental condition, sound level of the passing vehicle and speed of vehicle. “safety margin“was defined as the difference between the estimated crossing time and the time from when the vehicle was detected to when the vehicle arrived.
13	Fryer et al. (2013)	Comparing descriptions of familiar routes recalled by individuals of varying sight abilities to highlight the differences in navigation strategies.	Study Location: UK. 9 blind and partially sighted who were 1) registered blind for +10 years and independent, 2) experienced as long-cane users, 3) had completed school or college; 9 participants with full sight of comparable age, gender and educational background (Age range of full sample: 31–75 years).	Qualitative study. Individual interviews was used asking participants to imagine taking a familiar journey and to describe the route.	Participants with visual disabilities 1) identified most landmarks as multimodal with some auditory, while fully sighted identified mostly visual with some auditory, 2) noted absence of milestones while fully sighted could not, 3) identified most milestones as multimodal with some body-based then auditory, while fully sighted identified mostly visual then auditory, 4) used more words to describe routes, and used more proximal landmarks/milestones, 5) mentioned obstacles whereas fully sighted mentioned more distal milestones, 6) described more than one landmark at the same location, 7) referenced more to specific distance metrics. Participants with visual disabilities may resort to abstract methods like counting paces in absence of environmental information. Pure auditory information was used rarely by both groups perhaps because sounds can be both helpful and a hindrance. Smell was deemed as unreliable information. Body-based sensory information was reported for few landmarks and milestones and 3 blind participants referred to orientation of bodies in relation to fixed points. Though Street furniture helped orientation, they served as obstacles to be avoided for the most part (especially movable elements).
14	Goodrich and Ludt (2003)	To investigate the mobility performance of legally blind patients with age-related maculopathy (ARM) assessed through their ability to visually detect hazards on a travel path.	Study location: U.S.A. 60 participants with 78.6 average age having ARM. 10% used a cane, 21.7% used a mobility assistive device. Under half of them used sunglasses (filters).	Quantitative study. Distance visual recognition assessment (DVRA) used to examine ability to detect 3 types of hazards (drop-off, obstacle on surface, head-height obstacles) plus participant’s maximum potential visual detection distance (before training and after that).	There is a great diversity of distances at which each hazard is detected. Thus each hazard may place a greater or smaller percentage of travellers at risk of failing to detect the hazard. The percentages of participants having difficulty visually identifying the surface obstacle and the over-hang were smaller than that for the drop-off. The surface obstacle was the most easily detected type of hazard studied. With increase in training and filters, participants improved dramatically with great distances. The number of participants unable to detect the curb declined markedly, the surface obstacle was the most easily detected in all phases, and all subjects could detect the overhang after training and fitting with filters.
15	Guth et al. (2005)	The impact of roundabouts on pedestrian travel of individuals who are blind.	Study location: U.S.A. Experiment 1: 12 people including 6 blind (3 with guide dogs, 3 with canes), 6 normal vision (4 were O&M instructors for the blind), aged 23–56 travelled independently in urban areas- no dogs or canes were used however. Experiment 2: blind adults including 5 dog guide users, 5 long-cane users; the single-lane condition had 4 sighted participants (3 orientation and mobility instructors and 1 optometrist).	Quantitative study. Experiment one: participants tested to identify when they were able to cross three double-laned busy roundabouts. Experiment two: it happened at a (single-lane) roundabout, crosswalk, and an intersection. 30 trials per site for long-canes, 20 trials for dog guide, 60 with no device.	Experiment 1: Gaps were inversely related to traffic volume. Overall blind participants were slower to report crossable gaps and were more likely to indicate a crossable gap in case of insufficient time. They were as likely to miss a crossable gap as to report it while sighted participants reported crossable gaps more than twice as often as they missed them. Blind participants underestimated crossing gaps more often than sighted participants more for busier traffic roundabouts. Sighted participants sometimes pressed the button when a vehicle had cleared in front of them but not the entire width of the area which wasn’t observed in the blind group. Overall, sighted participants had insufficient time on 13.4% of crossing judgments compared to 28.9.% of blind group. Experiment 2: drivers almost always yielded at the campus location but rarely at downtown. At the roundabout, drivers yielded more to pedestrians waiting to cross at entry than those at the exit. Entry vehicles slowed to enter the roundabout and drivers had sight lines on participants but exit drivers were monitoring flow of vehicles more so than participants. Vehicles approaching the exit from the entry lane did not have clear sight lines until they were near the circulatory roadway therefore sometimes they didn’t look until they were close to the crosswalk. Yielding occurred most when pedestrians had a long cane, less when there was a dog guide and least with no device- drivers were however more influenced by the sites themselves rather than pedestrian characteristics.
16	Havik et al. (2012)	to provide a systematic overview of the appearance of Shared Spaces in the Netherlands, and the possible consequences of Shared Space for persons with visual disabilities.	Study location: Netherlands	Mixed Method study. Accomplished an evaluation of the features of shared spaces in terms of alignment with existing guidelines for accessibility which was followed by rating by a group of experts in orientation and mobility to determine the levels of barriers that shared space characteristics had for users with visual disabilities.	Serious common problematic characteristics of shared spaces in the observed locations are: 1) Absence of curbs or any other demarcation between stretches of road that can be perceived in a tactile way, 2) The possibility of cyclists riding on the section used by pedestrians, 3) A walking route that is not marked by a sufficient brightness contrast 4) Insufficient brightness contrast between carriageway and ‘pedestrian zone’ at the crossing, 5) Absence of tactile warnings in dangerous situations (e.g. crossings or stairs), 6) Absence of usable traditional guidance cues or guidance paths, 7) Absence of designated parking places and/or parking that is possible anywhere, 8) low detectability of the entrance and exit of a Shared-Space area. Positive characteristic of shared-spaces include: low speed limits, spaciousness, and good lines of sight that accommodate a good overview of the situation.
17	Havik et al. (2015)	A systematic assessment of wayfinding and navigation in the shared spaces and conventional spaces for people with visual disabilities.	Study location: Netherlands. 25 people including 11 blind and 14 partially sighted individuals with independent mobility.	Mixed methods study. Accompanied walks on 6 routes and a post-walk survey were used.	The navigations and orientation in shared spaces were more negatively experienced by participants with visual disabilities and they had difficulties in moving independently and had lower walking speeds compared to conventional spaces. Shared Spaces have less conventional traffic infrastructure which made it more difficult to navigate. Participants did not feel unsafe at both locations.
18	Hwang (2022)	To identify attitudes towards built environmental factors that facilitate or hinder the mobility of people with visual disabilities and people with physical disabilities	Study location: U.S.A. 46 people with visual disabilities	Qualitative study. Online survey was used.	Factors that represent participants’ attitudes towards the built environment include 1) barrier-free built environment (e.g. clear path to access points such as transit stops, road infrastructure incl. sidewalk, crosswalk, and intersections equipped with assistive devices, such as curb cuts, tactile surfaces, accessible signals), 2) built environment supporting safe travel (e.g. low speed limit, low traffic volume), 3) walkable built environment (e.g. land-use supporting high walkability without needing to use private vehicles). Participants without cars expressed more negative attitudes towards the neighbourhood-built environment in relation to barriers, safety, and walkability.
19	Jenkins et al. (2015)	To explore the role of sensory characteristics of the built environment in the use of public spaces by people with visual disabilities.	Study location: U.S.A. 85 people participated in this study were presidents and committee members of each state’s NFB (the largest organization of blind and low-vision people in the United States).	Qualitative study. Survey (rating and open-ended questions) was used.	Identified barriers include: 1) Population specific design: participants mentioned that often the spaces are designed for the sighted people and excludes the needs of population with visual disabilities which might lead to safety hazards, 2) Extreme sensory backgrounds: loud pedestrian noises mask the auditory signals and information which lead to difficulties in orientation and potential safety risks. Also, hybrid vehicles with little noise and absence of parallel traffic surges at street crossings is confusing for people with visual disabilities to cross the streets. 3) Uneven ground surfaces and objects: cracks, bumps, and drop-offs on the sidewalk cause falling risks. 4) Inconsistent lighting: causes shadows and low contrast signage are confusing for people with visual disabilities. Auditory, olfactory and somatosensory cues were identified to be important for orientation, mobility and participation of people with visual disabilities plus temperature and haptic cues were facilitators of using public spaces.
20	Kaminsky et al. (2014)	To explore the environmental facilitators and barriers to daily functioning of low-vision people due to diabetic retinopathy and the ways they use to adapt to the environment.	Study location: U.S.A. 8 participants with low vision resulted from diabetic retinopathy were selected purposefully.	Qualitative study. Semi-structured interviews, observation of participants’ home environment, and focus groups were applied.	Highly dynamic spaces that change significantly, visual distractions and uncertainty, such as traffic intersections, grocery stores, construction sites, and crowded public events were difficult to predict and navigate. Stairs and curbs were among the problems. Also, poor lighting and lack of contrast caused problems identifying and distinguishing features in the environment.
21	Koutsoklenis and Papadopoulos (2014)	To explore the most frequent haptic cues and the ways by which people with visual disabilities use them and investigate which are the most important for their outdoor wayfinding from their perspectives.	Study location: Greece. 32 individuals with visual disabilities (without other types of disabilities).	Mixed-methods study. Focus groups, questionnaire, and fully structured interviews were used.	Overall, 37 haptic cues were identified by the participants. Changes in the texture of walking surface, sidewalks, bus stops, slopes, curb ramps, walls, parking posts, traffic lights, flower beds, and potholes were the most significant haptic cues for the wayfinding of participants.
22	Laliberte Rudman et al. (2016)	To understand the process of social participation in daily life of older adults with age-related vision loss and to inform advocacy efforts and services for them.	Study location: Canada. 21 older adults (65+) with age-related vision loss in two Ontario cities.	Qualitative study Employed a grounded theory approach and used interviews, audio diaries, and life space maps to collect data with older adults.	The study found several limitations and facilitators for social participation in the areas of mobility options, physical environmental features, social environmental barriers, and sources of informal supports. Overall, participants reported a decrease in engaging in the social activities such as volunteering, walking or biking, going to movies, eating out, and shopping. Mobility Options including driving, using public transit, and walking/biking was restricted and difficult. Commonly mentioned physical barriers include: slippery surfaces, uneven curbs, inadequately maintained walking surfaces, stairs, and escalators. Several other physical environmental features were described as difficult, frustrating, or impossible to negotiate such as: traffic lights, busy intersections, darkness or inadequate lighting.
23	Landry et al. (2010)	To explore the efficiency and safety of warning tiles, their colours, and materials on blind people in winter conditions.	Study location: Australia. 24 participants with visual disabilities	Quantitative study. Participants were asked to do an experience on an outdoor semi-laboratory site by walking towards the 8 tiles indicated and stopping when detected. A questionnaire about the facility of detection and feelings of safety was also used.	The results showed both polymer and stainless-steel tiles are significantly detectable in winter weather with preference for Armor-tile (made of polymer). None of the results showed which tile was more slippery or safe.
24	Lauria (2017)	To discuss the accessibility to cultural heritage through description of a different tactile typology-Contrasting Walking Surface Materials (CWSM) and describes both negative and positive communicative capacity of the two types of tactile paving (Tactile Walking Surface Indicators and Contrasting Walking Surface Materials).	Study location: Italy. 24 blind participants	Quantitative study. Structured observation method including 4 tests in a controlled environment.	Tactile with the most contrast with the background paving was the most detectable by the blind participants. However, there were no clear relationship between contrast of friction and cue detectability. Some CWSM in the study showed high communicative potential specially when using long white cane. Trained participants were more skilled than the self-taught in detecting tactile cues.
25	Magnus (2016)	To investigate mobility and navigation challenges encountered by guide dogs and their users (e.g. people with visual disabilities)	Study locations: Sweden, Estonia, Germany. 36 guide dog users.	Qualitative study. Semi-structured interviews was used.	Difficult weather conditions (e.g. snow and ice) hinder movement, bury landmarks, and change the way sounds are heard. The absence of curbs (e.g. shared spaces) challenges the perception of a distinction between the pedestrian zone and road. Overhead objects (e.g. open windows, caution tape, tree branches) are difficult to detect from a distance (due to the difference in dogs’ height and their restricted field of vision). Temporary obstructions (e.g. construction, restaurant, or café furniture on sidewalk) can cause confusion and ignorance for the guide dog and the user. Acoustic cues can be lost due to 1) surrounding noise (due to traffic, machines, inclement weather), 2) quiet cars, silent movement of bikes, signals without sounds, and 3) multiple acoustic cues (e.g. beeping of different signals at the same intersection).
26	Maplesden (2012)	To present the travel skills used by people with visual disabilities to raise awareness for professionals working in this area and enhancing the safety of pedestrians with disabilities.	Study location: Australia. This study is based on the experience of the author working or walking alongside people with visual disabilities.	Qualitative study. Specific method is not determined.	Mental imagery of the surroundings is a conceptual skill and important for wayfinding. White vehicles and those with lots of glinting chrome are easier to see than dark cars and grey or metallic colours. Pedestrian facilities within a reasonable distance of busy roundabouts should be planned. Traffic noise help with orientation and quiet motor of an electric bicycle or hybrid/electric car can be a hazard. Detecting quiet vehicles in driveways or parking lots is especially difficult. Halfway refuges do reduce the complexity of judging both direction traffic but do not provide assurances of when it is safe to cross. A device that provides audio and a vibrating pulse is useful to warn to cross. Tactile Ground Surface Indicators (TGSI) are discerned by cane tip or colour contrast. Hazard bumps should be placed exactly opposite the next patch of bumps to walk towards, and a user’s feet should not be pointed towards the centre of an intersection. Above waist height objects can’t be detected by white cane. The boundaries of sidewalks are often helpful to stay on sidewalks. Raised sidewalks are preferred. Uncontrolled right slip lanes pose a danger. A clear building line is important to remain oriented on paths.
27	McGrath et al. (2017)	To explore how the environmental barriers of an ageist and disablist society are produced in socio-political context affecting the experience of older adults with age-related vision loss.	Study location: Canada. Through purpose sampling 10 older adults with age-related vision loss participated in this study, in a mid-sized Canadian city and surrounding rural communities.	Qualitative study. Applied a critical ethnography study (what is and what can be done about it?) using a modified version of Carspecken’s five-stage approach plus a narrative interview, a participant observation session, and a semi-structured interview.	While travelling outside their immediate neighbourhood, the participants reported fear of not being able to see the crosswalk traffic lights and not enough time to pass in busy intersections, fear of falling in different public spaces. Listening for traffic surges, planning trips ahead, using landmarks, visualizing a space, counting steps, using familiar routes, concentrating and being cautious, and asking for help were the strategies they used to overcome the barriers in terms of mobility.
28	McMullan and Butler (2019)	To investigate the self-regulations methods that older adults with visual disabilities used to ensure effective mobility scooter use and explore the barriers to participation, individuals’ strategies for managing their visual limitation, and the community mobility needs of this population.	Study Location: New Zealand. 15 participants aged + 60 with a variety of visual disabilities were part of the study using a purposive sampling.	Qualitative study.Used an interpretive description approach and a combination of go-along participant observation and semi-structured interviews, and optometry reports for data collection.	Self-regulations methods were categorized into 3 themes including:1) Reasons for getting a scooter: unavailability of accessible and affordable transportation options, enhancing their well-being and connection to the neighbourhood, independent travel behaviour, and autonomy, supporting social needs, to access safe space for walking, enhancing confidence, being less stigmatizing than wheelchair, and being easy to use. 2) Risks and barriers associated with using a scooter: many physical feature, personal limitations, and social environmental factors (e.g. change in terrain without contrast warning, collision with pedestrians or vehicles, footpath clutter, inaccessible or unsafe streets, lack of curb ramps and interesting spaces, poor footpath design and condition.3) Strategies used by scooter users: taking the environment, visual disabilities, and managing scooter risks into account. Environmental features to promote the effective use of scooters are:1) designated crossings: traffic lights, zebra crossings or pedestrian islands, 2) flat terrain and gentle slopes, 3) curbs with manageable ramps for street access, 4) parking space for a scooter, 5) pleasant areas, 6) shared pathways with minimal road crossings, 7) underpasses for busy roads.
29	McMullan and Butler (2019)	To answer the research question “what are the experiences of persons with low vision who use mobility scooters?” by providing user’s experiences.	Study location: New Zealand. 4 people with visual disabilities aged + 51 who use scooter regularly were part of this study using maximum variation sampling.	Qualitative study. Used a combination of methods including go-along, and semi structured interviews and a new measure of functional vision for mobility called the vision-related outcomes in orientation and mobility in 3 small and medium sized community locations.	3 themes were found including: 1) Autonomy and well-being: mobility scooters provide participants with more independence in their mobility compared to other means of travel, is protective, joyful, productive and help have different activities (leisure, self-care, etc.), 2) Accessibility: wide footpath, flat terrain, accessible kerbs, enough natural light were noted as facilitators of travelling. ‘Road crossing with audible tactile traffic lights provided a safe travel’. Lack of road crossings traffic lights, footpath damage and dips, driveways, narrow footpaths and entranceways, footpaths without lowered access to the road and footpath furniture were noted as barriers. 3) Community interactions: pedestrians were viewed as obstacles to be respected and footpath users’ movements, especially cyclists and children with skateboards and limited vision were noted as concerning. Participants were positive about asking for/offering help towards pedestrians, as well as entering the scooter’s community.
30	Montarzino et al. (2007)	To identify the personal, environmental, and transportation factors that have an impact on mobility and independence of people with visual disabilities.	Study location: Scotland 66 participants with 80.1 average age. Aetiologies include mostly macular degeneration 40% partially sighted, 8.3% legally blind.	Mixed methods study. Travel diary and questionnaire were used.	Important built environment and transportation factors include availability of crossing facilities to get to bus stops. Important personal factors include age, vision in better eye, and number of years one has lived in current address. Participants reported that during tourist/festival season it is difficult to navigate crowded spaces. Frequently cited issue was inadequate crossing facility which causes change of route. Main road crossings avoided by 83%. Neighbourhoods with crossings are avoided which impact activity level. Feeling of safety at audible crossing was reported; pros – more time to cross, cons – confusing signal sounds for vehicles. Traffic island are not preferred due to the proximity to high-speed traffic. Other identifies barriers include: parked cars, people swinging, doors open, street furniture, bollards, cycle racks, litter bins, public art, designed steps. Participants avoided: uneven pavements, busy hours, unfamiliar places, crowds, minor roads with no crossing facility. Participants reported feeling unsafe walking in unfamiliar places, and at night time. Important predictors of walking distance were reported to be feeling of safety and availability of crossing facilities.
31	Nuzzi et al. (2018)	To explore the use of different environmental aids among people with visual disabilities.	Study location: Italy. 100 individuals with mild, moderate, or severe visual disability or partial or total blindness whose average age was 59.	Quantitative study. Survey questionnaire was used.	Participants reported greater sense of safety in known versus unknown environments. Handrails and acoustic traffic lights considered most useful. Need for improvement was reported for the following features:1) bus stops with audio information signage, 2) lower height of traffic signals for better visibility, 3) acoustic traffic lights, 4) increased audibility of acoustic traffic signal to be heard over traffic noise, 5) sidewalks without level differences, 6) better signage indicating construction work, 7) better tactile guiding/warning surfaces (at crosswalk, parks, gardens), 8) high-contrast signs at crosswalk and street lighting at crosswalk, 9) Hazard signs to be placed at points where there is a sudden level difference, 10) Curb cuts should with lines parallel to, rather than perpendicular to crosswalk, 11) traffic island with tactile surfaces for crosswalks longer than 12 m, 12) barriers above ground (e.g. shelves, window sills, railings) that go undetected by white cane (should be placed) at higher heights or inside niches.
32	Papadopoulos et al. (2020)	To investigate the importance of different spatial information for people with blindness.	Study location: Greece, Cyprus, Turkey, and Germany. 115 adults including 79 with total blindness, 30 with profound vision loss, and 6 with legal blindness aged 18–64 years and 34.82 average age.	Quantitative study. Survey questionnaire was used.	In city centers and neighbourhoods participants cited the location of services, and wayfinding and orientation features as more useful than safety features. Greater importance attributed to features in city centre possibly due to greater complexity versus quiet/low-traffic nature of neighbourhood. Older adult participants ascribe a lower level of importance to location of services, and features for wayfinding and safety than adult participants. Safety features considered important include: traffic lights with audio signal, pedestrian streets/crossings, tactile paving. Different wayfinding features considered important depending on the type of environment (e.g. city centre versus neighbourhood) Auditory cues considered important (bus noises, sounds from park), as well as olfactory cues (bakeries, restaurants) and haptic (tactile paving) which serve as landmarks.
33	Park et al. (2017)	To identify and prioritize key issues in the outdoor journeys of people with visual disabilities.	Study location: New Zealand. 17 participants (6 with total blindness, 11 with partial blindness aged 45–64.	Qualitative study. Semi-structured interviews were used.	Key identified issues include: 1) Obstruction on footpaths (due to recycling bins, cars, low-hanging branches, undulating footpaths, defunct audio signals, poor street lighting, lack of footpath/crossing), 2) Barriers from construction (footpath closure, cones obstructing footpath, removal of tactile surfaces, noise)
34	Petraglia and Boudreau (2006)	To explore the mobility needs of people with visual disabilities.	Study location: U.S.A. People with low vision and blindness. Sample size and characteristics are not reported.	Qualitative study. Focus group and field survey were used.	Locator tones are important; particularly at ‘skewed’ intersections (not perpendicular). Right turn on red cause for concern. Locator tone should still be used even if there are two push buttons on the same post; tones should be out of phase to make them discernible. Crossing in a straight line is challenging – Locator tone can serve as beaconing to maintain one’s path. Beaconing to be avoided at free right turn lane and split phasing. Crossing time tends to be insufficient. Too many audio cues (for different directions at the intersection) can be overwhelming and difficult to follow. Tone preferred over voice to avoid comprehension difficulties associated with verbal prompts. Need for a standard tone that provides clear message. Traffic sounds could diminish the audibility of audio prompts at the crosswalk and vice versa. Tactile messages at the pole (at crosswalk) would require time to read. Braille messages would take longer to read. Pushbuttons to activate signal that do not provide confirmation (e.g. tone) can pose challenge to initiate crossing. It might be difficult to hear this tone due to traffic noise. Hence, despite the presence of accessible pedestrian signal, people experience delay in recognizing onset of pedestrian interval.
35	Ratelle et al. (2010)	To explore the accessibility needs of people with visual disabilities and develop a user-friendly tool.	Study location: U.S.A. People with visual disabilities.Sample size and characteristics are not reported.	Qualitative study. Tool validation (Details of validation methods are not specified).	Street furniture should be grouped in the same area and outside pedestrian zone; next to the street. Number of sidewalk ramps should be minimized to avoid veering outside pedestrian zone into street. Pedestrian zone of width 1500 m is appropriate; could be wider as needed but not too wide to avoid disorientation. Exterior stairs adjacent to pedestrian zone should be detectable by cane. Accessible pedestrian signal should eliminate risk of misinterpretation and pedestrian-vehicle conflict.
36	Routhier et al. (2021)	To evaluate the usability of detectable warning surfaces installed in Quebec City (Canada) with people with visual disabilities.	Study location: Canada. 19 individuals including 12 females and 7 males.	Qualitative study. Interviews were used for two locations: bus stops and intersections.	Challenges reported for using warning surfaces at bus stops include 1) closeness of warning surfaces to the road, 2) risk of colliding with the mirror on the side of the bus, 3) not being deep enough, 4) long distance between the location of warning surfaces and bus door. Benefits reported include: 1) improving participants positioning while waiting for the bus, 2) increased feeling of safety. At intersections, most participants referred to the utility of the installed warning surface and how it made it easier for them to get around. Participants proposed strategic locations to install warning surfaces mainly at busy intersections and main arteries. With respect to the detectability of the surfaces, the use of contrasting visual and/or tactile aspects depend on both the environmental context (e.g. wet VS dry surface, time of day) and the characteristics of individuals’ visual abilities. The degree of detectability of the warning surfaces in winter was raised as a concern since weather condition in Quebec is a significant factor (snow, ice, slush, salt, gravel, etc.).
37	Sakaja (2020)	To analyze the conceived space generated through the mobility practices of white cane users with visual disabilities.The study focused on spatial experiences and ways in which blind and severely partially sighted persons conceptualize (‘see’) urban space.	Study location: Croatia. 17 blind white cane users with varying histories of blind/visual disabilities	Qualitative study. Interviews were used to investigate participants’ experiences in navigation, encountered barriers, and their feelings.	Landmarks are the most frequently mentioned spatial element (both those distant and close) using touch, hearing, and smell for more close landmarks. Physical objects can be both barriers and landmarks (help avoid collision but can also cause falls). Sound can indicate direction and smells can indicate way (e.g. chocolate factories, fast food shops). Naming of streets, places are important to ask for help. Paths/routes are taken if familiar, creating a specific fragmented knowledge about the city. Choice of route is determined by accessibility and safety with tram transport as preferred. Edges are boundary breaks in continuity; if cutting across the route, they are barriers, especially in lanes without traffic lights. Edges that go along the direction of moving however serve as facilitators. Lateral edges as directional guides can be auditory to help partial sighted persons to identify all elements (traffic noises). Without edges, cane-users can’t maintain direction. Nodes are junctions and concentrations; large junctions have a lot of noise and traffic from either direction can be chaotic/disorienting (e.g. Plazas). Districts are places of a particular identity; blind people generate fragmented images of the city, making districts in their heads.
38	Suderman and Redmond (2015)	To understand how people with visual disabilities navigate signalized intersections.	Study location: Canada. Sample size/characteristics not reported (This study presents the results of research conducted by the City of Winnipeg over the 5-years)	Review and continuous dialogue with various stakeholders including the Mayor’s Access Advisory Committee, Canadian National Institute for the Blind (CNIB) and the visual disabilities Resource Network.	Building edges provide pedestrians with known landmark. Examples of edge: 1) Grass: universally understood and easily detectable for wayfinding, 2) Paved stone edge banding that provide sufficient visual contrast. Clear path of travel wider than 1.5 m. Path of travel should be free of obstacles (e.g. fire hydrants, streetlights) that disrupt wayfinding; should be moved to the amenity zone closer to the curb. Conflict may arise when pedestrians have to cross bike lane to get to transit stop, but having exclusive bike lanes makes for more comfortable sidewalk experience. Establishing a straight-line path ahead of time may not be possible in urban (particularly downtown) streets, thus requiring well oriented detectable warning surfaces to identify crossing alignment. Midpoint reference provided by traffic island/refuge may be helpful to cross wider roads. Sidewalk slope leading up to the ramp is a commonly accepted cue of change in elevation, should be 3–5%. There should be a raised curb (at least 2.3 m) between adjacent curb ramps at the corner of the intersection. If there is minimal separation, curbs should be continuous as smaller raised curbs pose tripping hazard. Large objects (e.g. bus shelters) alter the movement of air and reflect ambient noise, making them landmarks.Traffic sounds help in establishing straight path of travel to cross skewed intersections.
39	Wiciak et al. (2013)	To explore the effect of environmental sounds on orientation and mobility of blind and partially sighted people.	Study location: Poland. 244 individuals including 77 blind people and 167 partially sighted people aged 13–30 years.	Quantitative study. Survey questionnaire was used.	Noise from traffic (although some traffic sounds are helpful), engine roar, and construction machinery had negative effect on participants while pedestrian signal, and sounds characteristic of a place (e.g. church bell) had positive effect. Whereas the effect of wind and snow on sound reception more important for blind people, effect of fog is more important for partially sighted people. Effect of temperature and rain on sound reception is important for both groups.
40	Williams et al. (2014)	To explore navigation from the perspective of people with visual disabilities and the differences between navigation cues used by people with visual disabilities and cues used by people without visual disabilities.	Study location: USA Study 1: 18 individuals aged 30–66, with visual disabilities Study 2: 6 people with visual disabilities	Qualitative study. Focus groups, diary, observations of navigation by people with visual disabilities with sighted guides were used.	Stairs and doors are counted and used as landmarks to cue navigation. Tactile features, (e.g. slope and bumps on curb cut) indicate that there is an intersection. Not every object in/around the path of travel is an obstacle. The optimal path of travel is not necessarily one that is clear, wide, and open throughout. Wide open spaces are difficult to navigate because of lack of boundaries and cues. Boundaries are important for people with visual disabilities. Without boundaries, they can lose their direction. Role of boundaries (e.g. grass, fence) as cues for people with visual disabilities is in maintaining a straight path of travel. People with visual disabilities don’t mind hitting objects at cane level – that tells them to go around it. These are important ways of receiving feedback from the environment. However, overhead objects are a problem as they are hard to detect. When there is adequate sunlight, partially sighted people can detect contrast between grass and sidewalk.
41	Zeng (2015)	To explore the mobility experiences of people with visual disabilities.	Study location: Germany. 97 people with visual disabilities aged 19–63 with average of 38.3 years.	Quantitative study. Survey questionnaire was used.	Barriers include: 1) lack of audio information at transit stop, 2) unknown stairs, 3) roadside holes, 4) obstacles above waist level.
42	Zhao et al. (2018)	To understand the challenges experienced by people with low vision and how they cope with them when navigating surface level changes	Study location: U.S.A. 14 people with low vision aged 28–70 years.	Qualitative study. Structured interview and observation of navigation task performance were used.	Information needed to detect surface level change include: 1) how far it is, 2) how surface changes (e.g. direction, up/down), 3) position of level change, and 4) the depth of the surface change. Depth perception required to navigate surface level changes (e.g. potholes, steps, curbs) could be difficult for participants. Navigating steps and curb were the most challenging for participants. Outdoor stairs were the hardest for participants to detect. Visual highlights are the main cues to identify level changes rather than tactile feedback. Cues used to identify surface level changes include lighting and shading, colour, and texture. Shadows were an effective visual cue and relied on more than colour contrast. Shadows that cause illusions of stairs were however misleading. Bright sunlight could hinder detection of level change. Curbs were more challenging to detect than stairs. The absence of railing added to the challenge and increased risk of fall. Strategies to detect curb include: 1) occlusion cues (e.g. looking at car wheel by curb and knowing the presence of curb from seeing that the lower part of the wheel is blocked), and 2) shadows of the curb on the street or bending of shadow of branches over the curb. Surplus of shadows may be distracting rather than helpful.
					Painted (yellow) highlights helped in interpreting the location of the curb. Participants preferred walking on curb cut rather than stepping over curb to cross the street. Crosswalk lines and tactile domes with contrasting dark colour help indicate the location of curb cut at a distance. Participants take care while walking on surface level changes such as cracks, holes, and unevenness. Grouting lines give illusion of depth change. Obstacles (e.g. hydrants, poles, cones, trash cans) present on the side of the sidewalk were avoided by sticking to the centre of the sidewalk. Low obstacles were challenging.
43	Zimmermann-Janschitz et al. (2017)	To understand the mobility barriers and orientation cues that are used by people with visual disabilities.	Study location: U.S. 89 participants with blindness and vision loss in three age groups of > 20, 20–40, >50 years.	Quantitative study. Survey questionnaire was used.	Mobility barriers include: 1) fixed (signs, posts, streetlights, benches) and mobile (signs, adverts, racks) obstacles on sidewalks; 2) obstacles at/above waist height (not detectable by cane), 3) construction sites (scaffoldings, signs, sidewalk holes and cracks, closed sidewalk). Orientation and navigation cues include: 1) accessible pedestrian signals, 2) surface conditions, 3) the number of entrances to be passed, 4) stairs, 5) curbs, 6) fences, 7) walls. Participants who are partially sighted used the remainder of their vision to look for cues, such as 1) eye-catching buildings, 2) interplay of light and shadow, and 3) landmarks