Does aphasia impact on return to driving after stroke? A scoping review

Abstract

Purpose

Stroke can affect driving, an important activity of daily living. Little is known about whether aphasia (language impairment) impacts driving post-stroke. This scoping review explores impacts and perceived impacts of aphasia on driving performance, and the process of returning to driving post-stroke.

Materials and methods

Scoping review using Arksey and O’Malley’s framework, reported using the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Bibliographic databases were searched and international clinical practice guidelines were sourced online. Full-text articles were independently assessed by two reviewers. Results were tabulated and summarised using narrative synthesis.

Results

Forty-three literature sources and 17 clinical practice guidelines were identified. Six studies investigated return to driving with aphasia post-stroke; 37 sources from the broader literature contributed to objectives. It remains unclear whether aphasia impacts fitness-to-drive; however, people with aphasia face barriers in returning to driving due to: (1) uncertainty regarding the role of language in driving; (2) poor awareness and knowledge of aphasia, and (3) communication demands in the patient-journey and assessment.

Conclusions

The current evidence base is limited, inconsistent, and lacking in quality and recency and there is a lack of guidelines to support clinical practice. People with aphasia face barriers in returning to driving; however, it is unclear if aphasia affects fitness-to-drive post-stroke.

Implications for rehabilitation

• People with aphasia, their caregivers and clinicians have identified return to driving as a top 10 research priority.

• We do not know if aphasia affects fitness-to-drive post-stroke, but communication difficulties can make the process of returning to driving more difficult.

• Speech pathologists have an important role in ensuring that driving is discussed with people with aphasia post-stroke.

• Speech pathologists should support the multidisciplinary team to understand and meet the communication needs of people with aphasia throughout the driving evaluation process.

Keywords:

• Aphasia
• post-stroke
• driving
• rehabilitation
• community reintegration

Introduction

Driving post-stroke

Stroke is the leading cause of disability globally [1], and over 80 million people live with stroke worldwide [2]. Stroke may result in impairments in vision, visuoperception, motor control, cognition and behaviour that can significantly affect driving capacity [3–5], with 32–70% of stroke survivors unable to return to driving [6–9].

Driving cessation post-stroke is associated with significant psychosocial consequences including reduced community participation [8,10–15]; decreased social networks [14–16]; decreased meaningful life roles [14,15]; compromised self-identity [12–15]; and increased risk of depression [11].

Research into neuropsychological functions of driving demonstrates the importance of cognition and perception; with the components of executive function, processing speed, visuospatial skills, attention, memory, and mental flexibility, most frequently identified as predictive of fitness to drive [17]. A further common consequence of stroke is language impairment, termed aphasia. People with aphasia, their caregivers and clinicians have identified return to driving as a top ten research priority [18]; however, little is known about whether language difficulties impact driving function.

Aphasia post-stroke

Aphasia can impact all forms of communication including understanding of spoken information, reading, writing, speaking, non-verbal, and other symbolic means of communication [19]. Studies suggest that up to 41% of people will present with aphasia during the acute phase post-stroke [20] and for 34%, this language disability will become a chronic and continuing impairment [21].

Implications of aphasia on the driving task

Despite being a research priority, return to driving for people with aphasia has received limited attention in the literature. There is a lack of high-quality studies to inform the evidence base and clinical guidelines for return to driving for this cohort. A recent systematic review of stroke clinical practice guidelines informing aphasia management, identified an “aphasia-specific” information gap in “return to work, leisure, and driving” [22].

Wolfe and Lehockey [23] articulate logical concerns regarding the potential impacts of aphasia on return to driving:

From a face validity standpoint, drivers benefit from intact language functioning in order to read and understand road signs, potentially communicate with law enforcement, understand oral or visual instructions, read and understand driving laws, and pass written driving examinations. [23,p.523]

However, it is important to consider the evidence for such concerns and whether aphasia impacts day-to-day driving performance and safety.

Implications of aphasia in the process of returning to driving

A further important consideration is the impact aphasia may have on the process of returning to driving. The extant literature identifies barriers to return to driving for all stroke survivors. However, the presence of aphasia may lead to further complications in the patient journey.

International research demonstrates poor knowledge of healthcare professionals regarding legislation and guidelines relating to return to driving post-stroke [24–30]. Thus, health professionals may not be aware of recommendations relating to communication impairment.

A further barrier to return to driving for stroke survivors is a lack of information and education [14,15,31–37], yet those who do receive advice are six times more likely to return [6]. People with aphasia face particular difficulties in accessing healthcare information [38–44]. Health professionals limit conversations with patients with aphasia [44], and people with aphasia receive information for less time and on fewer topics in comparison to stroke patients without aphasia [39]. Accessibility and suitability of written information following stroke [38,40] are further concerns. Thus, people with aphasia may not receive or comprehend essential information regarding return to driving.

People with aphasia may also be disadvantaged by linguistic and communication demands in the assessment process. Whilst the on-road or behind-the-wheel assessment is considered the gold standard for driving [45–48], there is substantial variation in how much this contributes to final recommendations regarding fitness-to-drive, between 5% and 100% [46]. Clinic-based, cognitive assessments also inform decision-making [46,49–51]. Such tests are pen-and-paper or verbal-answer assessments rather than performance-based [46], and therefore require linguistic skills for completion. Participants must retain, understand and follow often complex task instructions with multiple steps or rules [52], thus receptive language difficulties may impact test performance. Pen-and-paper cognitive tests that do not require a verbal response are still significantly associated with auditory comprehension and naming [53]. Where a verbal response is required, expressive language difficulties may prevent a person with aphasia from conveying their answer successfully, thereby influencing task performance. Both receptive and expressive language deficits observed in aphasia may confound performance in off-road driving assessments.

In terms of ecological validity, the on-road assessment is considered the gold standard for driving [48]; however, the assessment process requires language skills which may not be needed in everyday driving. The examinee must retain, process, and quickly respond to the instructor’s verbal directions, without non-verbal cues to facilitate comprehension. The literature discusses the clinical practice of observing driving performance under different environmental conditions, including creating distractions (through intentional general discussion and asking questions) to assess attentional resources and allocation ability [54,55]. The requirement to divide attention to participate in conversation may disadvantage people with aphasia [56,57] and impact test performance and outcomes, despite not being a necessary part of everyday driving.

Research demonstrates poor awareness and knowledge of aphasia internationally, both within the community and amongst health professionals [58,59]. This may lead to inaccurate perceptions regarding the capacity and competence of a person with aphasia [60–62]. Health professionals report anxiety and reduced confidence when interacting with patients with communication difficulties and have inaccurate perceptions of the patient’s level of function [63]. There is a valid concern that language and communication difficulties could be misinterpreted as a lack of capacity or competence in driving assessment. Detailed consideration of the process of returning to driving after stroke highlights several areas of concern and risk of undue disadvantage for people with aphasia, warranting further exploration.

Review objectives

The aim of this review was to explore the question: “Does aphasia impact on return to driving after stroke?” In addressing this question, the authors sought to understand: (1) the impacts and perceived impacts of post-stroke aphasia on the driving task and (2) the impact of aphasia on the process of returning to driving post-stroke.

Materials and methods

Methodology

Preliminary searches revealed limited primary research investigating return to driving with aphasia. As such, a scoping review methodology was selected, to enable the authors to examine the extent, range and nature of the research evidence [64], in order to identify gaps in the literature and support planning and commissioning of future research [64,65–67].

Protocol and registration

The review protocol was developed using Arksey and O’Malley’s five-step methodological framework for scoping reviews [64], with reporting guided by the “Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guideline” [67].

Eligibility criteria

Inclusion criteria were: (1) literature regarding aphasia, or language/communication, in the context of the driving task, or the process of returning to driving post-stroke; (2) published sources including peer-reviewed journal articles and abstracts, book chapters, government reports, and clinical practice guidelines; (3) English language publications.

Exclusion criteria were: (1) literature related to the importance of driving and psychosocial consequences of driving cessation; (2) aphasia, or language/communication impairment resulting from aetiology other than stroke; (3) publications in a language other than English.

No limitations were placed on the date or type of publication. In addition to primary and secondary research evidence, the authors identified commentary or statements of opinion relating to the research topic in position papers and clinical texts. Such discussion was considered important, as this may both influence and reflect current views and practices regarding driving and aphasia post-stroke. Further to the literature search, the authors sourced medical fitness to drive and clinical practice guidelines for stroke from developed English-speaking countries (Australia, New Zealand, UK, USA, Canada, Ireland, and South Africa). All guidelines were included to enable the authors to examine whether aphasia was considered and the nature of any recommendations, to allow for a comparison of international practice.

Information sources

A systematic search of bibliographic databases was undertaken in October 2019 and repeated in March 2022, prior to submission. Searches were conducted in PubMed; CINAHL; Medline; Embase; Scopus; Web of Science; ProQuest Dissertation and Theses and The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library). Secondary search methods were used, including: (1) reviewing references and citations of included literature and (2) hand-searching of key journals identified by the research team. Medical fitness to drive and clinical practice guidelines for stroke were sourced online.

Search strategy

The search strategy was drafted by the first author, informed by preliminary reading on the topic and research team discussion, and reviewed and refined by an experienced university librarian. The authors anticipated that much of the literature on neuropsychological fitness to drive would originate from the fields of occupational therapy and neuropsychology; therefore, the decision was made to include broader terms relating to “aphasia”, e.g., communication/language impairment, combined with terms for driving and a medical diagnosis of stroke. The final search strategy for PubMed is provided in Appendix 1.

Selection of sources of evidence

Covidence screening software (Veritas Health Innovation, Melbourne, Australia) was used to manage the screening and selection of sources. Following the automatic removal of duplicates in Covidence, the first author screened titles and abstracts for potential relevancy and ongoing inclusion. Records selected for full-text review were read by the first author (HW) and a second reviewer (AR), who made an independent decision regarding inclusion, using outlined eligibility criteria. All decisions regarding exclusion were recorded in Covidence, with discrepancies resolved through consultation with a third reviewer (SW).

The first author searched references and citations of included literature by hand, identifying any potentially relevant sources not retrieved in the initial selection process. These sources were screened and assessed for eligibility in a replication of the full screening process.

Data charting process

Records selected for inclusion were reviewed by the first author (HW), who identified data pertaining to review objectives: (1) the impacts and perceived impacts of post-stroke aphasia on the driving task and (2) the impact of aphasia on the process of returning to driving post-stroke. Data were charted using bespoke data extraction forms customized from the Joanna Briggs Institute (JBI) methodology guidance for scoping reviews [68].

Data items

Data pertaining to review objectives, including quantitative and qualitative findings, statements of opinion and clinical practice recommendations were extracted. Data relating to source details (author/s, date, country) and source characteristics, including type of evidence (e.g., primary, secondary, statement of opinion) and type of publication (e.g., full-text article, conference abstracts and papers, government report, book chapter) were recorded. For primary research studies and conference abstracts, data regarding research design, participants and aim were extracted. For clinical practice guidelines, recommendations regarding aphasia, or communication impairment in the context of return to driving post-stroke were extracted. The absence of any recommendations was also noted.

Critical appraisal of individual sources of evidence

The Mixed Methods Appraisal Tool (MMAT) [69] was used to appraise the methodological quality of included studies with quantitative, qualitative, and mixed methods designs. The tool has two screening questions, followed by four further criteria to be evaluated to produce an “overall quality score” or “descriptive summary” of study quality [69,p.1].

Two reviewers (HW and HG) discussed criteria and reached a joint decision regarding scoring. The full results (including screening questions and criteria corresponding to study design) are presented, enabling discussion of the methodological quality of included primary research studies.

Synthesis of results

Due to broad inclusion criteria, a range of sources informing review objectives were identified, including: (1) research specifically investigating return to driving with aphasia; (2) incidental findings from the broader literature; (3) commentary or statements of opinion in position papers and clinical texts. To ensure an accurate representation of the extent, range, and nature of the research evidence [64], the decision was made to differentiate between research specifically investigating the topic, and incidental findings and commentary in the broader literature. As such, data were categorised and presented in the following phases:

1. Literature relating to the impacts and perceived impacts of aphasia on the driving task (objective 1); or literature relating to the impact of aphasia on the process of returning to driving (objective 2).

2. Literature from research specifically investigating return to driving with aphasia.

3. Incidental findings from the broader literature that further inform review objectives.

   1. These findings were further grouped into categories describing their contribution to the evidence base.

4. Commentary or statement of opinion on the topic.

Results were categorised and tabulated according to the phases outlined and summarised in a narrative synthesis.

Results

Selection of sources of evidence

A total of 793 records were identified through searches of electronic databases, with a further 132 records identified through secondary search methods. Following the removal of duplicates, a total of 526 citations were screened for title and abstract, with 421 deemed to be irrelevant. A total of 105 sources were assessed for eligibility, with 43 included in this review. See Figure 1 for source selection process and reasons for exclusion. Sources identified through searches of bibliographic databases are presented in Table 1. International medical fitness to drive and clinical practice guidelines for stroke from developed English-speaking countries identified through online searches are presented in Table 2.

Figure 1. PRISMA flowchart [70]: Source selection processes and reasons for exclusion.

A flowchart showing the source selection processes. Sources are separated into those identified via databases and registers and those identified via other methods. Information is displayed across the following phases: identification, screening and included.

Table 1. Source characteristics.

Reference	Country	Type of evidence	Type of publication	Research design	Aim	Participants	MMAT	Obj. 1 n = 38	Obj. 2 n = 21
Research specifically investigating return to driving with aphasia (n = 6)
Donovan et al. [71]	USA	Primary	Government research report	Quantitative non-randomized	To investigate aphasia’s effect on road sign interpretation accuracy and response time	n = 20 (a) + (b) 10 post-stroke with aphasia; (c) 10 neurologically normal controls	✓	✓	✓
Golper et al. [72]	USA	Primary	Full-text article	Quantitative non-randomized	(1) To analyse the self-judgement of driving competency in PWA; (2) to determine which tasks were most predictive of the overall team recommendation regarding returning to driving.	n = 20 (a) + (b) 20 post-stroke with aphasia	✓	✓	✓
Hartje et al. [73]	Germany	Primary	Full-text article	Quantitative non-randomized	To compare performance in a practical driving examination with performance in standardised neuropsychological tests for people with and without aphasia after acute neurological impairment.	n = 65 post-stroke/TBI (a) 53 post-stroke; (b) 34 PWA post-stroke; 2 PWA post-TBI.	✓	✓	✓
Lebrun et al. [74]	The Netherlands	Primary	Book chapter	Quantitative non-randomized	To determine the road sign interpretation skills of PWA.	n = 25 (a) 21 post-stroke; (b) 14 PWA; (c) 4 neurologically normal controls	✓	✓	✓
Mackenzie and Paton [76]	UK	Primary	Full-text article	Mixed methods	(1) To determine views and practice of medical practitioners and aphasia therapists on return to driving with aphasia post-stroke and the experience and effects for aphasic people of resuming or not resuming driving. (2) To compare the road sign recognition ability of PWA with a comparable non-stroke population.	n = 65 (a) + (b) 18 post-stroke with aphasia; (c) 18 neurologically normal controls; (d) 11 medical practitioners, 18 SLTs	✓	✓	✓
Matsko et al. [75]	USA	Primary	Conference poster abstract	Quantitative non-randomized	To explore the use of a numerical communication scoring system and simulated driving exercise as predictors of driving skill in an adult communication impaired stroke population.	n = 25 (a) 25 post-stroke with communication impairments; (b) PWA included but number not specified	✓	✓
Incidental findings/research evidence from the broader literature (n = 29)
Akinwuntan et al. [105]	Belgium	Primary	Full-text article	Quantitative non-randomized	To identify variables that best predict a team’s decision of driving ability in stroke patients from a pre-driving assessment.	n = 104 (a) 104 post-stroke; (b) 16 PWA	✓	✓
Aslaksen et al. [85]	Norway	Primary	Full-text article	Quantitative non-randomized	To examine the predictive value of standardized neuropsychological tests to predict on-road driving performance in patients with cerebral stroke or TBI, and to provide cut-off values.	n = 78 (a) 55 post-stroke; (b) LHD included but PWA not specified	✓	✓
Berger and Mensh [94]	USA	Primary	Full-text article	Qualitative	To use the experiences of a PWA to provide a guide for rehabilitation professionals.	n = 1 post-stroke with aphasia	✓	✓
Bliokas et al. [86]	Australia	Primary	Full-text article	Quantitative non-randomized	To evaluate the ability of a neuropsychological assessment battery to predict on-road outcome measures and explore relationships between individual neuropsychological tests and driving performance in individuals with acquired cognitive impairment.	n = 104 (a) 61 post-stroke; (b) PWA not specified	✓	✓	✓
Breen [92]	USA	Primary	Conference poster abstract	Quantitative descriptive	To investigate the characteristics and rehabilitation outcomes of stroke survivors who return to work.	n = 190 (a) 190 post-stroke; (b) PWA included but number not specified	✓	✓
Breen et al. [91]	USA	Primary	Conference poster abstract	Quantitative descriptive	To investigate the cost, length of treatment and characteristics of stroke survivors returning to work.	n = 96 (a) 96 post-stroke; (b) PWA included but number not specified	✓	✓
Breen et al. [90]	USA	Primary	Conference poster abstract	Quantitative descriptive	To investigate the frequency and characteristics of stroke survivors returning to work.	n = 96 (a) 96 post-stroke; (b) PWA included but number not specified	✓	✓
Fields and Unsworth [17]	Australia	Secondary	Full-text article	Systematic review	To identify the evidence base for including assessment of cognitive and perceptual skills within fitness-to-drive evaluations.	N/A		✓
Franklin et al. [18]	Ireland	Primary	Full-text article	Qualitative	To derive the shared top 10 research priorities of PWA, their carers and SLTs.	Survey n = 46 (a) + (b) 21 PWA; (d)18 SLTs; (e) 7 carers Consensus meeting n = 22 (a) + (b) 10 PWA; (d) 9 SLTs; (e) 3 carers	✓		✓
Howe et al. [95]	Australia	Primary	Full-text article	Qualitative	To explore the environmental factors that hinder or support the community participation of adults with aphasia.	n = 25 (a) + (b) 25 post-stroke with aphasia	✓	✓	✓
Kato et al. [93]	Unknown	Primary	Conference poster abstract	Quantitative descriptive	To introduce a drive recorder system as an evaluation tool for driving ability in real-life situations for stroke patients.	n = 3 (a) 3 post-stroke; (b) 1 PWA	✓	✓
Kerr et al. [116]	UK	Primary	Full-text article	Qualitative	To determine information needs and structure for a website about living with stroke.	n = 12 (a) 12 post-stroke; (b) 5 PWA	✓		✓
Lundqvist et al. [117]	Sweden	Primary	Full-text article	Quantitative non-randomized	To describe a model and clinical guidelines for determining driving fitness for patients with cognitive dysfunction in a rehabilitation setting.	n = 43 (a) 18 post-stroke; (b) PWA included but number not specified	✓		✓
Marino et al. [81]	Italy	Secondary	Full-text article	Systematic review	To identify and summarize scientific findings concerning the relationship between neuropsychological and clinical screening tests and fitness to drive in chronic conditions.	N/A		✓
Marshall et al. [3]	Canada	Secondary	Full-text article	Systematic review	To identify the most consistent predictors of driving ability post stroke.	N/A		✓
McCabe et al. [80]	Canada	Secondary	Full-text article	Systematic review	To evaluate interventions and strategies for community reintegration following brain injury.	N/A		✓
McKevitt et al. [96]	UK	Primary	Full-text article	Quantitative descriptive	To estimate the prevalence of self-reported need in community-dwelling stroke survivors across the UK.	n = 799 (a) 799 post-stroke (b) PWA not specified, but people with self-reported communication problems included.	✓	✓	✓
Nouri and Lincoln [83]	UK	Primary	Full-text article	Quantitative non-randomized	To validate a cognitive test battery, previously found to be predictive of on-road driving performance.	n = 40 (a) 40 post-stroke; (b) LHD damage included but PWA not specified	✓	✓
Nouri [104]	UK	Primary	Full-text article	Quantitative descriptive	To examine the knowledge and opinions of GPs on fitness to drive after a stroke.	n = 155 (d) 155 GPs	✓	✓	✓
Nouri et al. [82]	UK	Primary	Full-text article	Quantitative non-randomized	To produce a cognitive screening assessment to identify which post-stroke drivers would be safe to be assessed on the road.	n = 39 (a) 39 post-stroke; (b) LHD damage included but PWA not specified	✓	✓	✓
Perumparaichallai et al. [84]	USA	Primary	Full-text article	Quantitative non-randomized	To evaluate the cognitive and driving outcomes of a neurorehabilitation program and to examine the relationship between neuropsychological variables and driving outcomes.	n = 128 (a) 36 post-stroke; (b) PWA not specified	✓	✓
Phan et al. [107]	Australia	Primary	Conference poster abstract	Quantitative non-randomized	To discover patterns which lead clinicians to request driving tests after stroke.	n = 82 (a) 82 post-stroke; (b) 27 PWA	✓	✓
Radford and Lincoln [89]	UK	Primary	Full-text article	Quantitative non-randomized	To determine the concurrent validity of the Stroke Drivers Screening Assessment (SDSA).	n = 93 (a) 93 post-stroke; (b) PWA included but number not specified	✓	✓	✓
Rohde et al. [115]	Australia	Primary	Full-text article	Qualitative	To identify similarities and differences between client and therapist goals in rehabilitation for people with aphasia and explore reasons for any differences.	n = 7 (a) + (b) 4 post-stroke with aphasia; (d) 3 SLTs	✓		✓
Sagar et al. [88]	Australia	Primary	Conference poster abstract	Quantitative non-randomized	Exploration of the relationship between a patient’s initial stroke severity score (National Institute of Health Stroke Score/NIHSS) and passing driving test.	n = 81 (a) 81 post-stroke (b) PWA included but number not specified	✓	✓
Schanke and Sundet [87]	Norway	Primary	Full-text article	Quantitative non-randomized	To investigate the correspondence between neuropsychological test results and on-road driving performance among patients with a CT-verified brain damage or documented neurological disorder.	n = 55 (a) 43 post-stroke; (b) 18 PWA	✓	✓
Sjöqvist Nätterlund [114]	Sweden	Primary	Full-text article	Qualitative	To describe aphasic individuals’ experiences of everyday activities and social support in daily life.	n = 20 (a) + (b) 20 post-stroke with aphasia	✓		✓
Stack et al. [50]	Ireland	Primary	Full-text article	Quantitative descriptive	To investigate occupational therapy evaluation practices for fitness to drive after stroke in Ireland.	n = 47 (d) 47 OTs	✓	✓
Sundet et al. [106]	Norway	Primary	Full-text article	Quantitative non-randomized	To identify which neuropsychological measures are prioritised in the decision-making process regarding fitness to drive and to establish cut-off scores for sensitive tests.	n = 72 (a) 72 post-stroke; (b) 20 PWA	✓	✓
Commentary or statement of opinion (n = 8)
Bryer et al. [98]	USA	Commentary/review	Book chapter	N/A	Clinical text on “Driver rehabilitation and community mobility”.	N/A		✓	✓
Finestone and Gershkoff [99]	USA	Commentary/review	Book chapter	N/A	Clinical text on “Driving after stroke”.	N/A		✓	✓
Gershkoff and Finestone [100]	USA	Commentary/review	Book chapter	N/A	Clinical text on “Driving after stroke”.	N/A		✓	✓
Marx et al. [102]	Germany	Commentary/review	Full-text article	N/A	To provide a guideline for the assessment of driving ability after a diagnosis of cerebrovascular disease.	N/A		✓
Pellerito [101]	USA	Commentary/review	Book chapter	N/A	Clinical text on “Driver rehabilitation”	N/A		✓	✓
Taylor [97]	UK	Commentary/review	Clinical guideline	N/A	Historical clinical guideline	N/A		✓
van Zomeren et al. [103]	The Netherlands	Commentary/review	Full-text article	N/A	To evaluate whether anatomical structures in the brain can be related to aspects of the driving task.	N/A		✓	✓
Wolfe and Lehockey [23]	USA	Commentary/review	Full-text article	N/A	To provide a review of relevant research related to neuropsychological assessment of driving capacity and practical guidelines for clinicians.	N/A		✓

Participant key: (a) participants post-stroke; (b) participants with aphasia post-stroke (if known); (c) neurologically normal controls; (d) health professionals; (e) carers.

Table 2. International fitness to drive and stroke clinical practice guidelines (n = 17).

Country	Guideline	Aphasia/communication discussed	Summary of discussion
Australia	Austroads. Assessing fitness to drive for commercial and private vehicle drivers: medical standards for licensing and clinical management guidelines [4]	Yes	Specific comment that aphasia (comprehension of written and spoken language) may impact on fitness to drive (p. 155).^a Further commentary regarding the need for intact comprehension for safe driving (p. 8, 120, 152, 163).^a
	Clinical guidelines for stroke management. Stroke Foundation [131]	No
	Australian Competency Standards for Occupational Therapy Driver Assessors [113]	Yes	Discussion regarding screening communication skills as required for the driving task (Standard 2.11, p. 16).^a Details expectations for the assessment process including the need to follow instructions and obey all road signs and signals (Standard 3.5, p. 21).^b
UK	Driver & Vehicle Licensing Agency. Assessing fitness to drive: A guide for medical professionals [128]	No
	Royal College of Physicians. National clinical guideline for stroke, 5th ed. [109]	Yes	Specifies that persisting language impairment requires referral for on-road screening and evaluation (p. 56).^a Advice that many cognitive tests are not valid for PWA, and on-road assessment may be needed (p. 55).^b
NZ	Waka Kotahi NZ Transport Agency. Medical aspects of fitness to drive. A guide for health professionals [130]	No
	Clinical guidelines for stroke management. Stroke Foundation [131]	No
Canada	Canadian Council of Motor Transport Administrators. Determining driver fitness in Canada [118]	Yes	Specifies that the Mini Mental State Examination and similar tests are sensitive to language ability and education (p. 35).^b
	Canadian Medical Association. Determining medical fitness to operate motor vehicles: CMA driver’s guide ed., 9.1 [108]	Yes	Notes that although aphasia is not an absolute contradiction to safe driving, it requires attention and further evaluation (p. 87).^a
	Canadian stroke best practice recommendations: Rehabilitation, recovery, and community participation following stroke. Part two: Transitions and community participation following stroke [110].	Yes	Specifies that cognitive assessment should include a focus on reading/symbol comprehension (p. 800).^a
Ireland	National Office for Traffic Medicine. Slainte agus Tiomaint: Medical fitness to drive guidelines 10th ed. [129]	No
	Irish Heart Foundation. National clinical guidelines and recommendations for the care of people with stroke and transient ischaemic attack [132]	No
South Africa	South African-Contextualised Stroke Rehabilitation Guideline (SA-CSRG) [111]	Yes	Notes the requirement for sensory assessment, including reading comprehension (p. 105).^a Advises against assessing driving eligibility with cognitive tests if the person’s language impairment would invalidate their results (p. 105).^b
	South African Society of Occupational Medicine. Medical requirements for fitness to drive [133]	No
US	Guidelines for Adult Stroke Rehabilitation and Recovery: A guideline for healthcare professionals from the American Heart Association/American Stroke Association [134]	No
	National Highway Traffic Safety Administration. Driver fitness medical guidelines [135]	No
	Clinician’s Guide to Assessing and Counselling Older Drivers. 4th ed. [112]	Yes	Notes that a Driving Rehabilitation Specialist may be able to determine whether the person has an expressive aphasia, and can therefore interpret written stimuli, such as traffic signs (p. 126).^a Notes that traffic signs may be interpreted based on colour, shape, and symbol recognition (p. 126).^a Notes that PWA who demonstrate safe driving ability may fail to renew their license due to difficulties with the written examination. Advises that the clinician should urge the licensing authority to make reasonable accommodations. (p. 126)^b

^a Discussion regarding the role of language/communication in the driving task.

^b Considerations regarding language/communication in evaluation process.

Characteristics of sources of evidence

Of the 43 sources identified through bibliographic databases, only six specifically investigated return to driving with aphasia [71–76]. These studies all employed quantitative [71–75], or mixed [76] methods. Most were published in the late 1900s (n = 4), between 1975 and 1991 [72–75], with the remaining studies published in 2003 [76], and 2015 [71]. Half were published as full-text journal articles [72,73,76]. Remaining studies included a government report [71], book chapter [74], and a conference poster abstract [75].

A further 29 sources provided incidental findings, or research evidence from the broader literature. These included primary research studies (n = 25) (quantitative n = 19; qualitative n = 6) and systematic reviews (n = 4). Eight additional sources were identified which provided commentary or statements of opinion on the topic in position papers and clinical texts.

Further to sources identified through bibliographic databases, medical fitness to drive and clinical guidelines for stroke from developed English-speaking countries were identified (n = 17), with 41% (n = 7) commenting on potential impacts of aphasia on the driving task and 29% (n = 5) on communication requirements in the driving evaluation process, and considerations for people with aphasia.

Critical appraisal within sources of evidence

MMAT scores [69] (Appendix 2) demonstrate the overall low quality of research specifically investigating return to driving with aphasia. One study was identified as high quality [72] scoring 5/5 overall. Two studies scored 3/5 [71,73], and one study 2/5 [76]. The study by Matsko et al. [75] was published as a conference poster abstract with no subsequent publication and received a score of 0/5 due to insufficient detail. The final study [74] did not satisfy screening requirements. A common criterion of concern was that confounding factors that may “distort interpretation of findings” [69,p.1] had not been adequately accounted for in the study design and analysis. Studies providing incidental findings from the broader literature were also appraised using the MMAT, with scores presented in Appendix 2.

Results of individual sources of evidence

Extracted data are provided in a supplementary file. Table S1 presents data for objective one: the impacts/perceived impacts of aphasia on the driving task; and Table S2 presents data for objective two: the impacts of aphasia on the process of returning to driving post-stroke.

Synthesis of results

Results pertaining to objective 1: the impacts and perceived impacts of post-stroke aphasia on the driving task

Most sources (n = 38) related to the first review objective. This included investigation of return to driving with aphasia (n = 6); incidental findings from the broader literature (n = 24) (quantitative n = 18; qualitative n = 2; systematic review n = 4) and commentary or statements of opinion on the topic in position papers and clinical texts (n = 8) (see Table S1). Some current international clinical practice guidelines (n = 7) also discussed the impact of aphasia, or language impairment on driving (see Table 2).

Does aphasia impact on the driving task?

Findings from research specifically investigating return to driving with aphasia (n = 5): Two studies reported people with aphasia or communication impairment demonstrated impaired performance in simulated [75] and on-road [73] driving. Matsko et al. [75]compared informal communication ratings with simulated driving performance for stroke patients (n = 25). Those with communication scores within functional limits performed equally to non-stroke subjects, whereas those with scores below functional limits demonstrated poorer driving performance [75,p.552]. A full-text article was not published. With the limited information provided, there are concerns regarding the methodological quality of this paper, which received an MMAT score of 0/5. Thus, these results must be interpreted with caution.

Hartje et al. [73] compared performance in on-road driving with standardised psychometric test results for participants with aphasia (n = 36) and with acute neurological impairment but no aphasia (n = 29). Significantly fewer people with aphasia passed the on-road test (42%) than those without (72%). There was no correlation between performance in subtests of the Aachen Aphasia Test [77] (Token-Test; repetition; written language; naming and comprehension), or type of aphasia, and driving performance. However, no participants with global aphasia (n = 4) passed [73,p.165–166]. Within the group with aphasia, those who failed the driving test were significantly older, but age did not influence outcomes for participants without aphasia [73,p.170]. Performance in psychometric tests (measuring speed, visual orientation, and visual perception) was not predictive of on-road driving performance, for either the aphasic or non-aphasic group [73,p.165]. Study MMAT scores reflect methodological concerns regarding: (1) completeness of outcome data (criteria 3.3) and (2) accounting for confounding factors in study design and analysis (criteria 3.4). The results must be interpreted with caution, as causality between aphasia and poorer driving performance was not established.

Three studies investigated effects of aphasia on road sign recognition [71,74,76], and found aphasia impacts on accuracy [71,74,76], and response time [71,76]. Mackenzie and Paton [76] reported a significant interaction (p = 0.015) between severity of aphasia and performance in the Road Sign Recognition Test (RSRT) [76,p.113] from the Stroke Driver Screening Assessment [78]. Donovan et al. [71] found participants with aphasia were less accurate and required more time as road-sign language and symbols increased in complexity [71,p.15]. In contrast, Lebrun et al. [74] found severity of aphasia did not influence performance [74,p.64]. Both Donovan et al. [71] and Lebrun et al. [74] observed that both expressive and receptive aphasia could lead to difficulties in road sign recognition [71,p.16;74,p.63]. Importantly, Mackenzie and Paton [76] reported performance in the RSRT did not differentiate between aphasic participants who had (78%) and had not (22%) returned to driving [76,p.112].

A common methodological concern across these studies was that confounding factors were not accounted for in the design and/or analysis. Visual, perceptual, and cognitive factors that may affect performance were not measured or reported on. Indeed, Mackenzie and Paton [76] observed a “distinct trend towards a significant correlation” between performance on the RSRT and the Coloured Progressive Matrices pattern choice test [76,p.113;79], suggesting that non-linguistic skills may underlie performance in the RSRT.

Incidental findings from the broader literature (n = 19): The broader literature provided incidental findings regarding the role of language or aphasia in driving post-stroke (n = 12) and evidence of driving outcomes for people with aphasia (n = 7) (see Table S1).

A systematic review into predictors of driving ability post-stroke reported aphasia was predictive of on-road driving performance (p < 0.01) [3,p.108]. Two further systematic reviews described “communication” [80,p.251] and “language” [81,p.394], respectively, as functions required for driving. More recently, an overview of systematic reviews (n = 14) investigating cognitive and perceptual predictors of fitness to drive reported language function was predictive of driving fitness in 50% (n = 7) [17,p.332].

Primary research studies provided similarly mixed findings. Initially, Nouri et al. [78] found auditory comprehension was not significant in predicting driving test gradings [82,p.113]; however, in a later study, the authors found it was a significant factor in predicting performance [83,p.279]. Verbal working memory has also been found to predict driving performance post-stroke [84,p.3]. In contrast, tests measuring verbal function and verbal memory [85,p.1228]; verbal learning capacity [86,p.483]; auditory attention and verbal function [87,p.118] have been found not to predict performance. One study reported the presence of aphasia did not distinguish between those who passed or failed the driving test [88,p.548]. A further study reported on the role of non-linguistic factors, including visuospatial and executive abilities, in road-sign recognition [89].

The broader literature provided evidence of driving outcomes for people with aphasia. Quantitative research [90–92] and case studies [93] demonstrated that people with aphasia, even those with a severe aphasia [94] are successfully returning to driving. However, there was also evidence of changed driving status for this cohort. One study reported a change in driving status for 44% of participants with aphasia post-stroke [95]. A UK survey of 799 stroke-survivors found those with communication problems (number unknown) reported a significantly higher incidence in changes to transport and travel, than those without [96,p.1401].

Findings from commentary (n = 8): Commentary regarding the impact of aphasia on driving performance is inconsistent. An early guide for medical practitioners in the UK advised while “expressive dysphasia would not prevent ordinary driving… difficulty in understanding oral or visual instructions could clearly cause significant risk” [97,p.100]. More recent clinical texts covering driving evaluation for occupational therapists [98], stroke recovery and rehabilitation [99,100] and assessment in clinical gerontology [101] reported that “aphasia is sufficient to substantially compromise…” “fitness to drive” [98,p.166], and “driving performance”, respectively [101,p.697] and that “aphasia presents a challenge to driving” [99,p.797;100,p.699].

A more recent position paper reported "aphasia is not associated with unsafe driving” and “aphasic drivers do not differ significantly from healthy controls” in standard on-road testing [102,p.3]. The authors reported that only participants with global aphasia have demonstrated unsafe driving, and suggested this may be due to “additional neurocognitive impairments” [102,p.3]. Other papers provided a balanced view, and reported “mixed” [23,p.523] and “unclear” [103,p.22] findings regarding the role of language in driving and the impact of aphasia, respectively.

Reported concerns regarding driving and aphasia included: potential effects of aphasia on road sign recognition and interpretation [23,98,101]; difficulty in understanding oral or visual instructions when driving [23,97]; difficulty asking for or responding to directions or assistance [98,101,103] and communicating with law enforcement [23] and the need for intact language functioning to read and understand driving laws [23].

Does aphasia impact on decision-making regarding return to driving?

Findings from research specifically investigating return to driving with aphasia (n = 2): Golper et al. [72] compared the judgement of people with aphasia regarding their driving competency (n = 20), with the decisions of a multidisciplinary rehabilitation team. They found a significant relationship (p < 0.005) between the team-assigned driver and non-driver groupings and the participants’ own groupings, suggesting that aphasic participants had appropriately judged their competency to drive [72,p.36]. However, different factors contributed to the decision. Variables that distinguished the participants’ groupings included several aspects of communication: verbal expression (ranked 2nd); auditory expression (3rd) and gestural expression (6th). Whereas those distinguishing the team’s groupings included one aspect of communication: reading ability, which was ranked 8th [72,p.36]. Thus, people with aphasia deemed their communication difficulties to impact driving more profoundly, than the multidisciplinary team.

Mackenzie and Paton [76] investigated the views of medical practitioners (n = 11) and speech and language therapists (SLTs) (n = 18). They reported that 82% of medical practitioners believed that in certain circumstances driving with aphasia was contraindicated, and 64% were influenced by the presence of a communication difficulty when evaluating fitness to drive. Similarly, 61% of SLTs felt that, in some circumstances, driving with aphasia was contraindicated. One doctor believed that people with aphasia should retake the National Driving Test (for learner drivers), as did five (28%) of SLTs [76]

Auditory and reading comprehension were concerns for 64% of medical practitioners; around 33% cited road sign recognition specifically. Auditory comprehension and reading comprehension were considered important by 28% and 56% of SLTs, respectively; around 33% considered road sign recognition a concern. Only two therapists (11%) felt speech was a concern, and writing was not considered important by either group [76].

Incidental findings from the broader literature (n = 5): A study examining knowledge and opinions of GPs on fitness to drive post-stroke found that 55% of GPs would recommend those with auditory comprehension difficulties should not drive, and 91% considered “visual comprehension” deficits (which may include reading) incompatible with driving [104,p.102]. A more recent study reported 68% of occupational therapists would address driving in presentations of “mild expressive or receptive aphasia” [50,p.112].

Two studies found aphasia was not significant in predicting final multidisciplinary team recommendations regarding return to driving [105,p.338;106,p.54]. Aphasia was one of three factors “ranked the lowest” in leading clinicians to request driving tests post-stroke [107,p.545].

Do current clinical practice guidelines provide recommendations regarding return to driving with aphasia following stroke?

Some international clinical practice guidelines (n = 7; 35%) discussed the impact of aphasia, language, or communication difficulties on driving post-stroke. Medical fitness to drive guidelines from Australia and Canada, respectively, advised that aphasia “may” impact fitness to drive [4,p.155], and “requires the physician’s attention and further evaluation” [108,p.87]. Clinical guidelines for stroke from the UK recommended those with “persisting disabilities” including “language” should be referred for on-road screening and evaluation [109,p.56]. Stroke guidelines for Canada [110] and South Africa [111] recommended assessment of “reading/symbol comprehension”. American guidelines discussed interpretation of road signs, noting this may not be affected in expressive language deficits; furthermore, signs may “still be interpreted based on colour, shape, and symbol recognition” [112,p.126]. The “Australian Competency Standards for Occupational Therapy Driver Assessors” recommended screening of communication skills “as required for the driving task” [113,p.16].

Results pertaining to objective 2: does aphasia impact on the process of returning to driving post-stroke?

This section presents sources pertaining to the second review objective (n = 21). This includes investigation of return to driving with aphasia (n = 5); incidental findings from the broader literature (n = 11) (quantitative n = 6; qualitative n = 5); commentary or statements of opinion in position papers and clinical texts (n = 5) and recommendations in current clinical practice guidelines (n = 5) (see Table S2).

Findings from research specifically investigating return to driving with aphasia (n = 5): Investigation of healthcare knowledge regarding return to driving with aphasia found 55% of medical practitioners felt guidelines on return to driving with a communication difficulty were not “sufficiently clear” [76,p.113]. Gaps in SLT knowledge were also identified: only two therapists (11%) were aware of the mandatory driving cessation period post-stroke [76,p.114] despite 61% being asked for advice by a client with aphasia, and 44% by a relative [76,p.115]. Donovan et al. [71] noted “very little research has examined the effects of post-stroke aphasia on driving ability”; thus there is a lack of clinical guidance and recommendations relating to driving and aphasia post-stroke, creating a “dilemma” for health professionals [71,p.5]

Clinical practice may pose a further barrier. Mackenzie and Paton [76] reported that even though 82% of medical professionals expressed concern regarding return to driving with aphasia, only 27% sought consultation from SLTs [76,p.114]. Only 17% of SLTs recalled being asked for their opinion, yet 94% felt they should be involved in decision-making, and 89% thought family should be included [76,p.115]. Golper et al. [72] recommended speech pathology expertise to assist in decisions regarding driving candidacy and provide recommendations for testing procedures [72].

People with aphasia have returned to driving without professional consultation [72,76] and imposed their own restrictions on return to driving [72,p.36]. A lack of confidence [76,p.111], economic concerns and family pressure [72] may influence return to driving for people with aphasia. Medical professionals and SLTs have reported seemingly low numbers of people with aphasia post-stroke who wished to return to driving in their respective caseloads [76,p.113–114].

Studies investigating return to driving with aphasia have reported accommodations to reduce language load in assessments including: using questions requiring a “yes/no” answer; supporting comprehension with gesture and; avoiding questions using the words “right” or “left” or names of colours [74,p.64]. Lebrun et al. [74] used a model to assess road knowledge to provide an alternative to verbal responses, and context to assist comprehension [74]. Accommodations for testing vision are reported, including pointing to items in visual acuity and colour vision tests, as an alternative to naming [72,p.36]. Adaptation of written materials is also recommended [72,p.39]. Time restrictions have been shown to impact performance in off-road driving assessment for people with aphasia [76,p.112].

Several overall assessment considerations are reported. Importantly, Mackenzie and Paton [76] noted that “no standardised tests exist for assessment of language components that may be relevant to driving” [76,p.109]. Further, fitness to drive of people with aphasia cannot be adequately judged from performance in psychometric tests alone [73,p.170]. In their early work, Lebrun et al. [74] advocated for “extensive testing, which goes far beyond traditional neurological examination” [74,p.65].

Contributions from the broader literature (n = 10): A lack of knowledge and assessment guidance regarding return to driving with aphasia [82,p.110;103] has also been identified in the broader literature. A UK study found community-dwelling stroke survivors with self-reported communication problems reported significantly higher need for information regarding driving (p = 0.031), than stroke survivors whose communication was unimpaired (16.2% compared to 6.4%) [96]. Qualitative studies also identified a lack of information for people with aphasia [114,p.121], and that return to driving may not be prioritised by carers and SLTs [18,115,p.1305]. A further study suggested that people with aphasia may not pursue return to driving: when discussing information needs post-stroke, two cohorts of stroke survivors without aphasia raised return to driving; however, the cohort with aphasia did not [116,p.1181].

The speech pathologist’s role in supporting people with aphasia to return to driving is discussed, including referring clients, advocating for driving evaluation, targeting communicative aspects of driving-related goals in therapy, and as part of the driving assessment team [115,117,p.621].

Finally, the broader literature identified potential impacts of aphasia on driving evaluation and rehabilitation. Two studies reported that aphasia may confound performance in off-road assessment due to difficulties understanding instructions [117,p.621] and participating in tests requiring verbal skills [89,p.326]. Lundqvist et al. [117] recommended on-road assessment “to determine whether an individual with aphasia fulfils demands for attention, reaction speed, planning, and understanding and obeying traffic signs” [117,p.621]. Bliokas et al. [86] noted verbal learning capacity impacts the ability to “learn new rules or strategies… and to respond to instructor feedback or subsequent driving lessons” [86,p.483]. People with aphasia have expressed the requirement for a driving instructor specifically trained to accommodate their needs in on-road testing [95,p.1107].

Commentary/statements of opinion regarding driving and aphasia (n = 5): Clinical texts and handbooks [99–101] acknowledged aphasia can influence test performance and even prevent return to driving. Professionals without specific training in communication, (including the Driver Rehabilitation Specialist (DRS) in America, and the Occupational Therapy Driver Assessor (OTDA) in Australia) are responsible for evaluating clients’ communication abilities as part of the overall assessment. The literature described the role of the DRS to “assess the patient’s current communication status”, “anticipate” problems during testing, and “urge the testing or licensing agency to make accommodations for the patient’s needs” [99,p.802–803;100,p.704–706]. Potential difficulties included “completing written or oral examinations and following the driving instructor’s verbal instructions during an on-road assessment” [99,p.803]. It is acknowledged that “some with severe deficits may fail” because they are “untestable” or “necessary accommodations” cannot be provided [99,p.803;100,p.706]. The exclusion of people with aphasia from research [98,p.172;103,p.21] and driver training programs [103,p.22] was also noted.

Recommendations to accommodate the communication needs of people with aphasia included: allowing extra time to complete assessments; waiving the written test; use of multiple-choice questions as opposed to prose or essay responses; tests designed using pictures instead of words and; reading questions and options for answers aloud [99,p.803]. Accommodations for testing vision are also reported, including the use of “visual acuity slides using number stimuli or tumbling Es” [101,p.97].

Clinical practice recommendations (n = 5): Five of the 17 included international clinical practice guidelines discussed considerations regarding language or communication in the assessment process. The “Australian Competency Standards for Occupational Therapy Driver Assessors” [113] noted the requirement to “follow instructions” during the on-road assessment and described the OTDA’s role to ascertain communication skills (expressive and receptive) with the client.

Other guidelines acknowledged the potential impact of aphasia during driving evaluation. The UK stroke guidelines noted: “Many cognitive tests are not valid for people with aphasia for whom on-road assessment may be needed” [109,p.55]. Similar statements are included in the Canadian fitness to drive guidelines which highlighted the sensitivity of the Mini Mental State Examination and similar tests to language ability and education [118,p.46], and the South African stroke guidelines, which recommended health professionals “do not assess driving eligibility with cognitive tests if the person’s language impairment would invalidate their results” [111,p.105]. American guidelines identified potential difficulties with written examinations and highlighted the clinician’s role to “urge the licensing authority to make reasonable accommodations for the… language deficit” [112,p.126].

Discussion

Summary of evidence

Impacts and perceived impacts of aphasia on the driving task

Research investigating return to driving with aphasia post-stroke is limited, lacking in recency and of overall low quality. Only six studies [71–76] have sought to address this topic, and MMAT scores [69] identified concerns regarding methodological rigour and reporting quality (see Appendix 2). Although these studies reported poorer performance of people with aphasia in various aspects of driving, including simulated [75] and on-road [73] driving, and tests of road-sign recognition [71,74,76], confounding factors which may have influenced results were not adequately accounted for. Two studies [71,76] compared people with aphasia with a neurologically normal cohort, whilst the remaining studies [73–75] failed to provide data regarding concomitant stroke sequelae known to impact driving performance.

Investigation of road sign recognition has been prioritised [71,74,76]. Evidence suggests a significant relationship between road sign recognition and performance in on-road driving [78,119], and the concern that road sign recognition may be affected in aphasia is logical, given the requirement to interpret written and symbolic language. However, road sign recognition is influenced by non-linguistic factors [76], including visuospatial and executive abilities [89], and causality between aphasia and impaired road sign recognition has not been established.

Furthermore, research has been conducted in a clinic environment [71,74,76] lacking ecological validity. Drivers use cues from their surroundings to support comprehension of road signs [120], and the physical environment and situational context affect real-world communication in aphasia [121]. Thus, clinic-based assessment is unlikely to represent a person with aphasia’s ability to comprehend and respond to road signs in the driving task.

The broader literature provides mixed findings regarding the role of language in driving post-stroke. An overview of 14 systematic reviews found language function was predictive of fitness to drive in 50% [17]. Primary research studies provide similarly varied findings. Auditory comprehension [83,p.279] and verbal working memory [84,p.3] have been found to predict driving performance post-stroke; in contrast, tests measuring verbal function, memory, and learning capacity were not predictive of fitness to drive [85,p.1228;86,p.483;87,p.118].

Further research is needed to understand whether aphasia impacts fitness to drive. People with aphasia have been excluded from research into driving post-stroke [8,122–125], or their inclusion is unclear. This review identified studies which reported the inclusion of people with left hemisphere strokes but did not specify the number of participants with aphasia [82–86]. The unclear inclusion of people with aphasia is a concern across stroke trials and protocols [126]. Other studies included participants with aphasia but failed to differentiate driving outcomes for this population [87,90–92,127]. The exclusion of people with aphasia from research into driving post-stroke means it remains an area of uncertainty and inconsistency, with a lack of guidelines to support clinical practice.

The literature shows that despite a lack of robust evidence, GPs [76,104], speech pathologists [76], and occupational therapists [50], consider that aphasia may impact fitness to drive. Commentary in clinical texts and handbooks [23,97–103] is characterised by differing interpretations and representations of the limited literature, and at times is inconsistent with the strength of the available evidence.

Concerns regarding driving and aphasia include: effects on road sign recognition and interpretation [23,71,72,74,76,98,101]; difficulty understanding oral or visual instructions [23,97]; interacting with others [72], including to ask for or respond to directions or assistance [98,101,103] and communicate with law enforcement [23] and; the need to read and understand driving laws [23]. Such considerations do not preclude driving in foreign countries, where the language and road sign conventions may not be understood. Additionally, difficulty communicating is not considered a barrier to driving for people with profound deafness, except in the case of commercial licenses [4,108,112,128–130]. Thus, further investigation is needed to understand why these factors might be considered important for people with aphasia.

International fitness to drive and stroke clinical practice guidelines reflect inconsistencies in the evidence base, with some (35%) pointing to the potential impact of aphasia, language, or communication impairment on the driving task; whilst the majority do not mention aphasia specifically. Where aphasia is discussed, the language used is often ambiguous [4,p.155;108,p.87], highlighting the ongoing uncertainty.

Impacts of aphasia on the process of returning to driving

This review also sought to understand whether aphasia impacts on the process of returning to driving post-stroke and identified barriers across the patient journey. Receiving information and education is crucial to return to driving post-stroke. Indeed, those who receive advice are six times more likely to resume driving [6]. However, this review identified a lack of information and guidance [96,114]. People with aphasia may return to driving without professional consultation [72,76], or impose self-restrictions on driving [72,76,116], due to reduced confidence [76] and a belief their communication difficulties may impact driving [72]. Goal setting poses another area of concern, as health professionals, partners, and carers may not understand the importance of return to driving [18], or address this goal with clients with aphasia [76,115].

People with aphasia face barriers due to language and communication requirements inherent in off and on-road components of driving assessment. There is acknowledgement in the literature [73,117] and international clinical practice guidelines [109,111,118], that aphasia may confound performance in off-road cognitive assessments, as such on-road assessment is recommended [109,117]. However, there is a lack of consistency and standardisation in driving assessment processes internationally [46,49–51]. Numerous assessments are used to inform decision-making regarding fitness to drive [46], thus there is a risk that decisions may be based on cognitive assessment results, which cannot be considered reliable for people with aphasia. Communication requirements in the on-road assessment may also disadvantage people with aphasia, including difficulty following the driving instructor’s verbal instructions [99]. Indeed, people with aphasia have expressed the need for a driving instructor specifically trained to work with aphasic clients [95].

Strategies to accommodate people with aphasia and facilitate their participation in assessments have been reported for written tests [72,99,112], and visual screening [72,101], in particular. Other accommodations include reducing the language load in assessment tasks, use of total communication strategies [74] and allowing extra time for assessments [76,99]. The literature emphasises the importance of multidisciplinary evaluation and decision-making for people with aphasia [72,117] including a speech pathologist [72,76,101,115,117] to ensure “optimal conditions for a fair judgment” [117,p.621].

This review identified a lack of clear guidelines to support assessment of return to driving for people with aphasia [76,82]. The literature [72,99], and some clinical practice guidelines [110,111], discuss assessment of language or communication as part of driving evaluation, including assessment of reading or symbol comprehension. However, no robust or reliable evidence exists to support such inclusions and there are no standardised tests to assess aspects of language that may be relevant to driving [76]. People with aphasia will evidently be disadvantaged if assessment of their communication skills unnecessarily contributes to decision-making regarding their fitness to drive.

Stakeholder awareness and understanding of aphasia will influence driving outcomes. Poor awareness and knowledge of aphasia amongst health professionals [58,59] may lead to language and communication difficulties being misconstrued as a lack of capacity or competence [60–62] during driving evaluation. Without a good understanding of aphasia, those involved in driving assessment for this population will not have the knowledge or competency to appropriately assess communication needs, anticipate linguistic requirements and potential difficulties with the assessment process [99], and facilitate the participation of people with aphasia. Ineffective communication between health professionals, key stakeholders, and people with aphasia [63] may create a further barrier for this population in return to driving after stroke.

Limitations

This scoping review focussed specifically on discussion of driving and aphasia post-stroke. Evidence from other aetiologies including traumatic brain injury, dementia, and specific language impairment could provide further information about the role of language in driving; however, such studies were not included in this review. The broad search strategy enabled inclusion of incidental findings from the broader literature, and commentary or statements of opinion pertaining to driving and aphasia post-stroke. The authors acknowledge that this strategy may not have identified all references to driving and aphasia in the extant literature; however, this review has established important and novel themes for future research. Discussion regarding the importance of driving for people with aphasia and the consequences of driving cessation for this population was considered beyond the scope of this review; however, this is an important area, warranting further research.

Conclusions

People with aphasia, their families and clinicians have identified return to driving after stroke as a top 10 research priority [18]. This scoping review provides a comprehensive, holistic, and original review of the literature on driving and aphasia post-stroke and identifies important considerations for future research.

Previous investigation of this topic is limited, lacking in recency, and of overall low-quality. Future research should account for confounding factors in driving outcomes for people with aphasia, including visual, perceptual, and cognitive impairments. Future studies should also aim for ecological validity, recognising the significance of situational context in real-world communication in aphasia. Further research is also needed to understand current perspectives regarding driving with aphasia, including the origins and rationale for these beliefs. It is not possible to estimate the number of people with aphasia who are not able to return to driving and future research should attempt to quantify the extent of this problem.

People with aphasia face unique barriers in return to driving post-stroke due to a complex interaction between uncertainty about the role of language in driving, low levels of awareness and knowledge of aphasia, and linguistic and communication demands in the patient-journey and evaluation process. Future research must explore the patient journey for people with aphasia in returning to driving after stroke to understand these barriers and identify factors which may support this population to return to driving. Finally, future research should aim to understand the lived experience of driving loss post-stroke for people with aphasia and consider the unique challenges and impacts that this population may face in managing driving cessation.

Disclosure statement

Helen Wallace, PhD Candidate, Queensland Aphasia Research Centre, The University of Queensland. Mrs. Wallace has no relevant financial or nonfinancial relationships to disclose. Dr. Hannah Gullo, Conjoint Research Fellow, Occupational Therapy, employed by The University of Queensland. Dr. Gullo has no relevant financial or nonfinancial relationships to disclose. Professor David Copland, Professorial Research Fellow employed by The University of Queensland. Financial - No relevant financial relationship exists. Nonfinancial –Director, Queensland Aphasia Research Centre; Co-director Centre of Research Excellence in Aphasia Recovery and Rehabilitation, Australia. Annette Rotherham, PhD Candidate, Queensland Aphasia Research Centre, The University of Queensland. Mrs. Rotherham has no relevant financial or nonfinancial relationships to disclose. Associate Professor Sarah Wallace, NHMRC Emerging Leadership Fellow, employed by The University of Queensland. Financial - National Health and Medical Research Council NHMRC Emerging Leadership Investigator Grant. Nonfinancial – Collaboration of Aphasia Trialists Research Officer.

Additional information

Funding

This work was supported by the Australian Government Research Training Program Scholarship awarded to Helen Wallace and National Health and Medical Research Council NHMRC Emerging Leadership Investigator Grant awarded to Associate Professor Sarah Wallace.

Appendix 1.

Search strategy for PubMed

(((((((((((((aphasia[Title/Abstract] OR aphasic[Title/Abstract]) OR dysphasia[Title/Abstract]) OR dysphasic[Title/Abstract]) OR "language disorder"[Title/Abstract]) OR "language impairment"[Title/Abstract]) OR "communication disorder"[Title/Abstract]) OR "communication impairment"[Title/Abstract]) OR "cognitive communication"[Title/Abstract]) OR "aphasia"[MeSH Terms]) OR "language disorders"[MeSH Terms]) OR "communication disorders"[MeSH Terms]) OR "rehabilitation of speech and language disorders"[MeSH Terms]) AND (((((((((driving[Title/Abstract] OR drive[Title/Abstract]) OR driver[Title/Abstract]) OR "motor vehicle"[Title/Abstract]) OR automobile[Title/Abstract]) OR car[Title/Abstract]) OR "automobile driving"[MeSH Terms]) OR "drive"[MeSH Terms]) OR "motor vehicles"[MeSH Terms]) OR "automobiles"[MeSH Terms])) AND ((((((((stroke[Title/Abstract] OR "cerebrovascular accident"[Title/Abstract]) OR CVA[Title/Abstract]) OR "brain injury"[Title/Abstract]) OR "brain injuries"[Title/Abstract]) OR "head injury"[Title/Abstract]) OR "stroke"[MeSH Terms]) OR "brain injuries"[MeSH Terms]) OR "craniocerebral trauma"[MeSH Terms])

Appendix 2.

MMAT scores

Table

Part A: Research specifically investigating return to driving with aphasia (n = 6)
Quantitative non-randomized studies (n = 5)
Reference	Aim	Participants	Screening question 1: research question	Screening question 2: data address research question	3.1. Participants representative of target population	3.2. Appropriate measurements	3.3. Complete outcome data	3.4. Confounders accounted for	3.5. Intervention/exposure as intended	MMAT score/5
Donovan et al. [71]	To investigate aphasia’s effect on road sign interpretation accuracy and response time.	n = 20 (a) + (b) 10 post-stroke with aphasia; (c) 10 neurologically normal controls	Yes	Yes	Yes	Yes	Can’t tell	No	Yes	3/5
Golper et al. [72]	(1) To analyse the self-judgement of driving competency in PWA; (2) to determine which tasks were most predictive of the overall team recommendation regarding returning to driving.	n = 20 (a) + (b) 20 post-stroke with aphasia	Yes	Yes	Yes	Yes	Yes	Yes	Yes	5/5
Hartje et al. [73]	To compare performance in a practical driving examination with performance in standardised neuropsychological tests for people with and without aphasia after acute neurological impairment.	n = 65 post-stroke/TBI (a) 53 post-stroke; (b) 34 PWA post-stroke; 2 PWA post-TBI.	Yes	Yes	Yes	Yes	Can’t tell	No	Yes	3/5
Lebrun et al. [74]	To determine the road sign interpretation skills of PWA.	n = 25 (a) 21 post-stroke; (b) 14 PWA; (c) 4 neurologically normal controls	No	Can’t tell	Yes	Yes	Yes	No	No	N/A (3/5)
Matsko et al. [75]	To explore the use of a numerical communication scoring system and simulated driving exercise as predictors of driving skill in an adult communication impaired stroke population.	n = 25 (a) 25 post-stroke with communication impairments; (b) PWA included but number not specified	Yes	Yes	Can’t tell	Can’t tell	Can’t tell	No	Can’t tell	0/5

Table

Mixed methods (n = 1)
Reference	Aim	Participants	Screening question 1: research question	Screening question 2: data address research question	5.1. Adequate rationale for mixed methods design	5.2. Components effectively integrated	5.3. Outputs of integrated components adequately interpreted	5.4. Divergences and inconsistencies adequately addressed	5.5. Components adhere to quality criteria	MMAT score/5
Mackenzie and Paton [76]	(1) To determine the views and practice of medical practitioners and aphasia therapists on return to driving with aphasia caused by stroke and the experience and effects for aphasic people of resuming or not resuming driving. (2) To compare the road sign recognition ability of PWA with a comparable non-stroke population.	n = 65 (a) + (b) 18 post-stroke with aphasia; (c) 18 neurologically normal controls; (d) 11 medical practitioners, 18 SLTs	Yes	Yes	No	No	Yes	Yes	No	2/5

Table

Qualitative component of Mackenzie (2003) study
Reference	Aim	Participants	Screening question 1: research question	Screening question 2: data address research question	1.1. Qualitative approach appropriate for RQ	1.2. Data collection methods	1.3. Findings derived from data	1.4. Interpretation of results substantiated by data	1.5. Coherence between data sources, collection, analysis, and interpretation	MMAT score/5
Mackenzie and Paton [76]	To determine the views and practice of medical practitioners and aphasia therapists on return to driving with aphasia caused by stroke and the experience and effects for aphasic people of resuming or not resuming driving.	(a) + (b) 18 post-stroke with aphasia; (d) 11 medical practitioners, 18 SLTs	Yes	Yes	Yes	Yes	Yes	No	No	3/5

Table

Quantitative non-randomized component of Mackenzie (2003) study
Reference	Aim	Participants	Screening question 1: research question	Screening question 2: data address research question	3.1. Participants representative of target population	3.2. Appropriate measurements	3.3. Complete outcome data	3.4. Confounders accounted for	3.5. Intervention/exposure as intended	MMAT score/5
Mackenzie and Paton [76]	To compare the road sign recognition ability of PWA with a comparable non-stroke population.	(a) + (b) 18 post-stroke with aphasia; (c) 18 neurologically normal controls	Yes	Yes	Yes	Yes	Yes	No	Yes	4/5

Table

Part B: Contributions from the broader literature (n = 25).
Quantitative non-randomized studies (n = 12)
Reference	Aim	Participants	Screening question 1: research question	Screening question 2: data address research question	3.1. Participants representative of target population	3.2. Appropriate measurements	3.3. Complete outcome data	3.4. Confounders accounted for	3.5. Intervention/exposure as intended	MMAT score/5
Akinwuntan et al. [105]	To identify variables that best predict a team’s decision of driving ability in stroke patients from a pre-driving assessment.	n = 104 (a) 104 post-stroke; (b) 16 PWA	Yes	Yes	Yes	Yes	No	Yes	Can’t tell	3/5
Aslaksen et al. [85]	To examine the predictive value and provide cut-off values for standardized neuropsychological tests to predict on-road driving performance.	n = 78 (a) 55 post-stroke; (b) LHD included but PWA not specified	Yes	Yes	Yes	Yes	Can’t tell	Yes	Yes	4/5
Bliokas et al. [86]	To evaluate the ability of a neuropsychological assessment battery to predict on-road outcome measures and explore relationships between individual neuropsychological tests and driving performance.	n = 104 (a) 61 post-stroke; (b) PWA not specified	Yes	Yes	Can’t tell	Yes	Yes	No	Yes	3/5
Lundqvist et al. [117]	To describe a model and clinical guidelines for determining driving fitness for patients with cognitive dysfunction in a rehabilitation setting.	n = 43 (a) 18 post-stroke; (b) PWA included but number not specified	No	Can’t tell	Yes	Yes	Yes	No	No	N/A (3/5)
Nouri et al. [82]	To produce a cognitive screening assessment to identify which post-stroke drivers would be safe to be assessed on the road.	n = 39 (a) 39 post-stroke; (b) LHD included but PWA not specified	Yes	Yes	Yes	Yes	Yes	No	Yes	4/5
Nouri and Lincoln [83]	To validate a cognitive test battery, previously found to be predictive of on-road driving performance.	n = 40 (a) 40 post-stroke; (b) LHD included but PWA not specified	Yes	Yes	Yes	Yes	Can’t tell	No	Yes	3/5
Perumparaichallai et al. [84]	To evaluate the cognitive and driving outcomes of a neurorehabilitation program and to examine the relationship between neuropsychological variables and driving outcomes.	n = 128 (a) 36 post-stroke; (b) PWA not specified	Yes	Yes	Yes	Yes	Can’t tell	No	Yes	3/5
Phan et al. [107]	To discover patterns which lead clinicians to request driving tests after stroke.	n = 82 (a) 82 post-stroke; (b) 27 PWA	Yes	Yes	Yes	Yes	Can’t tell.	Can’t tell.	Can’t tell.	2/5
Radford and Lincoln [89]	To determine the concurrent validity of the Stroke Drivers Screening Assessment (SDSA).	n = 93 (a) 93 post-stroke; (b) PWA included but number not specified	Yes	Yes	Yes	Yes	Yes	Yes	Yes	5/5
Sagar et al. [88]	Exploration of the relationship between a patient’s initial stroke severity score (National Institute of Health Stroke Score/NIHSS) and passing driving test.	n = 81 (a) 81 post-stroke (b) PWA included but number not specified	Yes	Yes	Yes	Yes	Can’t tell	Can’t tell	Can’t tell.	2/5
Schanke and Sundet [87]	To investigate the correspondence between neuropsychological test results and on-road driving performance among patients with a CT-verified brain damage or documented neurological disorder.	n = 55 (a) 43 post-stroke; (b) 18 PWA	Yes	Yes	Yes	Yes	Can’t tell	Yes	Yes	4/5
Sundet et al. [106]	To identify which neuropsychological measures are prioritised in the decision-making process regarding fitness to drive and to establish cut-off scores for sensitive tests.	n = 72 (a) 72 post-stroke; (b) 20 PWA	Yes	Yes	Yes	Yes	Can’t tell.	Yes	Yes	4/5

Table

Quantitative descriptive studies (n = 7)
Reference	Aim	Participants	Screening question 1: research question	Screening question 2: data address research question	4.1. Sampling strategy	4.2. Sample representative	4.3. Measurements appropriate	4.4. Risk of nonresponse bias low	4.5. Statistical analysis	MMAT score/5
Breen [92]	To investigate the characteristics and rehabilitation outcomes of stroke survivors who return to work.	n = 190 (a) 190 post-stroke; (b) PWA included but number not specified	Yes	Yes	Yes	Can’t tell	Yes	Yes	Yes	4/5
Breen et al. [91]	To investigate the cost, length of treatment and characteristics of stroke survivors returning to work.	n = 96 (a) 96 post-stroke; (b) PWA included but number not specified	Yes	Yes	Yes	Can’t tell	Yes	Yes	Yes	4/5
Breen et al. [90]	To investigate the frequency and characteristics of stroke survivors returning to work.	n = 96 (a) 96 post-stroke; (b) PWA included but number not specified	Yes	Yes	Yes	Can’t tell	Yes	Yes	Yes	4/5
Kato et al. [93]	To introduce a drive recorder system as an evaluation tool for driving ability in real-life situations for stroke patients.	n = 3 (a) 3 post-stroke; (b) 1 PWA	No	Can’t tell.	Can’t tell	Can’t tell	No	Can’t tell	No	0/5
McKevitt et al. [96]	To estimate the prevalence of self-reported need in community-dwelling stroke survivors across the UK.	n = 799 (a) 799 post-stroke (b) PWA not specified, but people with self-reported communication problems included.	Yes	Yes	Yes	Yes	Yes	Yes	Yes	5/5
Nouri [104]	To examine the knowledge and opinions of GPs on fitness to drive after a stroke.	n = 155 (d) 155 GPs	Yes	Yes	Yes	Yes	Yes	No	Yes	4/5
Stack et al. [50]	To investigate occupational therapy evaluation practices for fitness to drive after stroke in Ireland	n = 47 (d) 47 OTs	Yes	Yes	Yes	Yes	Yes	Can’t tell	Yes	4/5

Table

Qualitative studies (n = 6)
Reference	Aim	Participants	Screening question 1: research question	Screening question 2: data address research question	1.1. Qualitative approach appropriate for RQ	1.2. Data collection methods	1.3. Findings derived from data	1.4. Interpretation of results substantiated by data	1.5. Coherence between data sources, collection, analysis, and interpretation	MMAT score/5
Berger and Mensh [94]	To use the experiences of a PWA to provide a guide for rehabilitation professionals.	n = 1 (a) + (b) post-stroke with aphasia	No	Yes	Yes	Can’t tell	No	No	No	1/5
Franklin et al. [18]	To derive the shared top 10 research priorities of PWA, their carers and SLTs.	Survey n = 46 (a) + (b) 21 PWA; d)18 SLTs; (e) 7 carers Consensus meeting n = 22 (a) + (b) 10 PWA; (d) 9 SLTs; (e) 3 carers	Yes	Yes	Yes	Yes	Yes	Yes	Yes	5/5
Howe et al. [95]	To explore the environmental factors that hinder or support the community participation of adults with aphasia.	n = 25 (a) + (b) 25 post-stroke with aphasia	Yes	Yes	Yes	Yes	Yes	Yes	Yes	5/5
Kerr et al. [116]	To determine information needs and structure for a website about living with stroke.	n = 12 (a) 12 post-stroke; (b) 5 PWA	Yes	Yes	Yes	Yes	Yes	Yes	Yes	5/5
Rohde et al. [115]	To identify similarities and differences between client and therapist goals in rehabilitation for people with aphasia and explore reasons for any differences.	n = 7 (a) + (b) 4 post-stroke with aphasia; (d) 3 SLTs	Yes	Yes	Yes	Yes	Yes	Yes	Yes	5/5
Sjöqvist Nätterlund [114]	To describe aphasic individuals’ experiences of everyday activities and social support in daily life.	n = 20 (a) + (b) 20 post-stroke with aphasia	Yes	Yes	Yes	Yes	Yes	Can’t tell.	Yes	4/5

Participant key: (a) participants post-stroke; (b) participants with aphasia post-stroke (if known); (c) neurologically normal controls; (d) health professionals; (e) carers.