A retrospective chart review of the patient population accessing augmentative & alternative communication at an urban assistive technology center

ABSTRACT

The purpose of this study was to 1) identify and describe the population seeking alternative and augmentative communication (AAC) evaluations at an assistive technology (AT) center in the Midwestern United States and 2) describe the AAC device features or services participants identify as most important at their initial AAC evaluations. Charts of 53 participants seeking AAC interventions at an AT center in the Midwestern United States were retrospectively reviewed. Information from the QUEST 2.0 was used to determine what AT features were identified as most important. The majority of participants seen at the AT center had progressive diseases. Across all of the participants, ease of use and effectiveness were identified as the “most important” aspects of an AAC device satisfaction. These findings highlight the importance of determining who is accessing AAC services across AT centers to determine whether barriers to AAC services exist. Moreover, patients report regarding what variables they deem as most important reflect the fact that excellent service-delivery may not overcome the importance of other variables, such as ease of use that impact AAC use.

KEYWORDS:

• adults
• augmentative and alternative communication
• service delivery

Introduction

Assistive technology includes equipment, devices, apparatuses, services, systems, processes, and environmental modifications that improve the quality of life of individuals with disabilities and older adults (Hersh & Johnson, 2008). Augmentative and alternative communication (AAC) is a subset of assistive technology (AT) that provides individuals who are unable to rely on natural speech an alternative way to fully access, participate in, and influence their environment (Beukelman & Miranda, 2013). Nearly 97 million individuals worldwide and five million Americans cannot rely on their natural speech to communicate making them candidates for AAC (Beukelman & Light, 2020). Given that communication is an essential human right (UN General Assembly, 1948), it is critical to ensure that everyone who is a candidate for AAC is able to pursue that option if they choose. An important first step in this process is determining who is pursuing AAC intervention services. With technology playing an ever-increasing role in our lives, it is likely that some, though not all, individuals who are pursuing AAC may have previous experience with technology (e.g., smartphones, tablets). It is possible that these individuals may have already developed specific ideas around what features are most important to them.

A wide array of individuals are candidates for AAC (Beukelman & Light, 2020; Lenker et al., 2005), including individuals with congenital disabilities and individuals with acquired disabilities (American Speech-Language-Hearing, n.d.). For individuals with congenital disabilities, such as autism spectrum disorder and cerebral palsy, the AAC device facilitates language acquisition and literacy development, while also serving as their primary communication system. In contrast, many individuals with acquired disabilities such as cerebrovascular accidents, amyotrophic lateral sclerosis (ALS), progressive aphasia, and traumatic brain injuries have already acquired natural speech and language. For these individuals, an AAC device provides an alternative way to communicate, since they are now unable to rely on natural speech. Although individuals with congenital and acquired language impairments may benefit from AAC, speech-language pathologists (SLPs) do not always recommend AAC systems (Dietz et al., 2020; Fried-Oken et al., 2012; Hustad & Miles, 2010). For example, SLPs typically focus on restoring the natural speech of patients with sudden-onset aphasia and often terminate services once a patient’s natural speech production progress has plateaued (Fried-Oken et al., 2012). Forty-seven percent of the speech-language pathologists (SLPs), working in a variety of clinical settings including private practice (21%), hospitals (17%), and schools (40%), they found that 47% reported that they almost never or rarely recommend use of an AAC system (Marvin et al., 2003). Approximately 33% report that they occasionally recommend the use of an AAC system (Marvin et al., 2003). Yet, even with a limited number of SLPs recommending AAC systems, the need for AAC service delivery may have outpaced service provision (Siu et al., 2010; Sutherland et al., 2005). A survey of AAC use and service provision in New Zealand revealed that 500 children and adults were awaiting initial or follow-up AAC evaluations (Sutherland et al., 2005) and in Hong Kong only 1 of the 599 children who were identified as having little or no functional speech was receiving AAC services (Siu et al., 2010). It is notable that although both studies suggest limited AAC service provision, they were conducted over a decade ago and do not provide information about services in the United States. Within this research study, we sought to begin collecting baseline data regarding who is currently pursuing AAC evaluations by describing the population seeking AAC evaluations at an AT center in the Midwestern United States as well as the features or services participants identify as most important to their satisfaction at their initial AAC evaluations.

When we are determining who is pursuing AAC evaluations in the United States, we must also provide a comprehensive description of the population in order to begin to understand how participant-specific traits may impact AAC intervention outcomes (Pennington et al., 2007). Even when participants have the same diagnosis, participant-specific traits (e.g., cognition, fine motor skills) may influence AAC outcomes. For example, when researchers investigated the outcomes of 38 participants with ALS, they found that although people with ALS could benefit from AAC, acceptance of the AAC device depended on the “patients milieu, personality, cognitive skills and the technology of the device as well as early and professional introduction” (Körner et al., 2013, p. 24). In other work, researchers found the primary reasons that participants with ALS rejected an AAC device were associated with the participant’s cognitive impairments (Ball et al., 2004). Together, these studies illustrate the importance of documenting participant-specific traits when conducting research with people who pursue AAC.

In addition to identifying and describing the adult population seeking AAC evaluations, we sought to determine what AT features participants identify as most important to them at the initial AAC evaluation. Technology is pervasive in our society. For most people, smartphones, computers, and tablets play an integral part in their daily lives. As such, adults seeking AAC evaluations are likely to have preconceived notions about what AT features they consider important. While previous research has investigated device satisfaction (Caligari et al., 2013; Ferriero et al., 2012), identifying patients’ initial ideas about the features they consider most important can help researchers and clinicians better understand how these preconceived notions may influence later device satisfaction as well as what SLPs may need to consider and discuss with patients as they make device recommendations.

Objectives

The purpose of this research study is to add to our understanding of who is pursuing AAC services. An understanding of who is pursuing AAC services is foundational to developing, implementing, and sustaining an AT service delivery program based on evidence-based practices. Firstly, we sought to identify and describe the population pursuing AAC evaluations at an AT center in the Midwestern United States. The AT center, where data collection took place, is located in a large, metropolitan area and accepts a wide range of funding sources to assist with AAC procurement. It was predicted that the population pursuing AAC at this particular AT center would be diverse. Secondly, the study sought to identify what AT features or services patients identified as most important to better understand what preconceived notions patients had in their initial AAC evaluations.

Method

This retrospective chart review study received approval from the University Institutional Review Board. Chart reviews were conducted at an AT center in the Midwestern United States. The AT center includes an interprofessional team that provides services five days per week. The AT services are based on the model described by Cook and Polgar (2015), and include seating and mobility, AAC, driver rehabilitation, electronic aids to daily living, computer access, and assistive technology for cognition. The interprofessional team includes a psychiatrist, SLP, rehabilitation engineer (RE), and multiple physical therapists (PT) and occupational therapists (OT). The SLP, RE, OTs, and PTs all have advanced certifications, specifically RESNA assistive technology professional, RESNA seating, and mobility specialist or ADED certified driver rehabilitation specialist. The AT service delivery model is based on a framework where the person who requires AAC is at the center of the process. The service delivery includes multiple phases (from referral and assessment to implementation and follow-along) and takes place over multiple appointments. A closed-loop feedback model is utilized for quality improvement. This center provides AAC device prescription and intervention services for adults with disabilities, as well as for adults with acquired speech and communication disorders due to brain injury, spinal cord injury, stroke, and neurological complications. A member of the research team randomly selected 61 charts from patients who did not have an open encounter at the AT center. The patients had been seen for AAC services at the AT center between the years of 2016 and 2018 and had been discharged from services. Four of the 61 patient charts were not included in the study because they were used by the research team to determine what information was present in the charts, to aid in the development of the coding schema, and to serve as training charts for the research assistants who coded the charts. The remaining 57 charts were reviewed to determine if they met the inclusion criteria for the study. Most adult AAC research has small sample sizes, with many studies including fewer than 10 participants (e.g., Griffith et al., 2014; Hamm & Mirenda, 2006). As such, we determined that 61 charts would enable us to adequately describe the patient population who had been seen and subsequently discharged from the AT center, while also enabling us to develop a coding schema (n = 4) and account for patient charts that would not meet the inclusion criteria for this study (n = 3).

Participants

Researchers reviewed the charts of 57 adults receiving care from an AT center in the Midwestern United States. Because this research study focused on describing the population seeking AAC evaluations and determining what AAC device features or services participants identified as most important at their initial AAC evaluations, the chart reviews focused on episodes of care provided by the SLP at the AT center because at this AT center the SLP is the primary point of contact for AAC evaluations. The SLP pulls in other disciplines for AAC evaluations, as needed, and is responsible for writing the funding report. Researchers obtained information on participant demographics (gender, age, and education), participant characteristics, AAC device status, access method, device prescribed, and participant outcome data during the chart review. Individuals with incomplete medical charts (n = 3) or those who were not prescribed a device (n = 1) were excluded from the study due to inadequate data in the participant’s medical charts. Data are reported for the 53 participants with complete medical records related to the constructs of this study.

Data collection

Researchers obtained the following information from each participant’s chart: diagnosis, physical status, sensory status, oral motor skills, receptive language, expressive language, cognitive skills, social interaction, and primary mode of communication. Sensory status refers to the participant’s current vision, hearing, and physical status. Oral motor skills refer to the use and function of the lips, tongue, jaw, teeth, and the hard and soft palates; this also includes motor speech and vocal parameters. Social interaction refers to the ability of the participant to participate in functional conversation including facial expressions, eye contact, and appropriateness in response.

An initial review of four charts that were not included in the study indicated a need to develop a coding schema that enabled us to account for the variability in the information reported across charts (e.g., differences in the number of assessments, etc). We subsequently determined that creating ratio scores would enable us to broadly capture information about each participant’s speech, language, cognitive, social and motor abilities. Ratio scores were calculated for each participant’s oral motor skills, motor speech, vocal parameters, receptive and expressive language, cognitive functioning, and social interaction. Ratio scores were calculated by dividing the number of skills that were reported to be within functional limits by the total number of measures in that area. For example, in the area of receptive language, the clinician may have assessed up to four different aspects of receptive language. A participant reported to have skills within functional limits for two of the four aspects have a ratio score of .5 (2 areas of receptive language reported to be within functional limits/4 areas of receptive language assessed = .5). However, if only three measures of receptive language were reported on within the chart, the participant would have a receptive language score of .67 (2 areas of receptive language reported to be within functional limits/3 areas of receptive language assessed = .67) Ratio scores ranged from 0 to 1. Information about the patient’s visual and hearing status typically involved self-report. If the patient’s vision and hearing were reported to be within functional limits when the patient wore their glasses or hearing aids, hearing and vision were reported within functional limits.

With regard to AAC device status, researchers coded whether or not this was the first time that a participant was being prescribed an AAC device, the type of AAC device prescribed, and access method. Due to our focus on describing the population seeking AAC as well as the device features or services participants identify as most important, we chose not to report on the specific devices prescribed to the patients. This approach is consistent with Frick et al. (2022) who noted “Though comparisons could be made across specific manufacturers, this information would quickly become obsolete due to rapidly changing offerings by these companies” (p.6). Moreover, this information may take away from the research questions of interest.

Access methods were categorized as follows: direct selection (e.g. touch, eye gaze, head pointing), joystick, or one or two switch scanning. Following training by the primary researchers, two undergraduate research assistants obtained demographic, patient characteristic, AAC device status, access method, and prescription data from each chart. Approximately 20% of the charts (n = 11) were coded for inter-rater reliability, which was calculated to be 92.32% (range = 87% to 95.7%).

The QUEST 2.0 (Demers et al., 1996) was used to determine what AT features were identified as most important at the initial AAC evaluation. The QUEST has been used in previous research measuring AT device satisfaction by asking patients’ what AT features were most important to them (Caligari et al., 2013; Ferriero et al., 2012). The QUEST 2.0 is a 12-item survey, which assesses participant satisfaction across an individual’s assistive technology device and service delivery. The majority of the questions are framed as a Likert scale asking participants to identify the degree to which they are satisfied with a certain aspect of the assistive technology and intervention. The scale ranges from 1, which indicates that the participant was not at all satisfied, to 5, which indicates that the patient was very satisfied (Demers et al., 1996). At the end of the survey participants are asked to select the three items that they consider “most important” from the following list: dimensions, weight, adjustments, safety, durability, easy to use, comfort, effectiveness, service delivery, repairs/servicing, professional service, follow-up services. The QUEST 2.0 has high test–retest stability and adequate validity (Demers et al., 2002). This assessment tool was administered by clinicians at the AT center as part of the standard service delivery process and quality improvement program.

Data analyses

Descriptors were calculated for each variable of interest. To describe the patients being seen at the AT center we calculated the average age of the participants and reported participants educational levels. In addition, we reported the number of participants with each diagnosis and calculated the percentage of participants who were diagnosed with developmental disorders, non-progressive and progressive diseases. To provide insight into the vision, hearing and motor abilities of the patients seen at this AT center, we calculated the percentage of patients who were to have hearing and vision within functional limits as well as the percentage of patients who were reported to be ambulatory, ambulate with difficulty or assistance, and used a power or manually operated wheelchair. Mean ratio scores were calculated to capture the speech, language, cognitive, and social abilities of this sample.

Results

The charts of 53 participants (31 males, 22 females) ranging in age from 24 to 82 years old with a mean age of 53 years (SD = 15 years) met the study inclusions criteria. The participants’ level of education ranged from not completing high school (n = 4) to completing a post-graduate program (n = 1), with the majority of participants terminating their education after receiving their high-school degree (n = 19). Twenty-three participants did not report their level of education. Patients had a variety of primary diagnoses including aphasia as a late effect of stroke/cardiovascular accident (n = 7), primary progressive aphasia (n = 2), ALS (n = 20), anoxic brain injury (n = 1), bilateral hearing loss (n = 1), cerebellar ataxia (n = 1), cerebral palsy (n = 8), head and neck cancer (n = 3), hereditary and idiopathic peripheral neuropathy (n = 1), Huntington’s Disease (n = 4), mental retardation (n = 1), motor neuron disease (n = 1), Multiple Sclerosis (n = 1), Parkinson’s Disease (n = 1), and quadriplegia (n = 1). It is notable that although AAC is not typically recommended for individuals with hearing loss, in this instance an AAC device was recommended because the individual uses American sign language to communicate and often does not have an interpreter with them. Please refer to Table 1 for a detailed reporting of patients’ sociodemographic data.

Table 1. Participant demographic information.

Participant Variables			n (%)
Gender
		Male	31 (59)
		Female	22 (41)
Education
		Less than high school	4 (8)
		High school	17 (32)
		Some college	2 (4)
		College	6 (11)
		Post-graduate	1 (2)
		Not reported	23 (43)
Diagnosis
		Progressive disease	38 (72)
		Non-progressive	10 (19)
		Developmental	5 (9)
Sensory Status
	Vision	WFL	51 (96)
		NWFL	2 (4)
	Hearing	WFL	52 (98)
		NWFL	1 (2)
	Physical	Ambulatory	16 (30)
		Ambulates with difficulty	5 (9)
		Ambulates with assistance	9 (17)
		Wheelchair	23 (43)
	Primary Mode of Communication	Verbal	35 (66)
		Gestures	2 (4)
		Sign	1 (2)
		Low-tech AAC	5 (9)
		High-tech AAC	2 (4)
		Other	4 (7)
		Not reported	4 (8)

WFL = within functional limits, NWFL = not within functional limits.

Ninety-six percent of participants in the sample had vision (n = 51) and 98% had hearing (n = 52) abilities within functional limits. Thirty percent (n = 16) were ambulatory, 26% were reported to ambulate with difficulty (n = 5) or assistance (n = 9), and 43% (n = 23) used a power or manually operated wheelchair. Participants had a mean oral motor ratio score of 0.39 (SD = .23), a mean expressive language skills ratio score of 0.59 (SD = .36), a mean receptive language skills ratio score of 0.88 (SD = .23), a mean cognitive abilities ratio score of 0.99 (SD = .06), and a mean social interaction abilities ratio score of 0.88 (SD = .28).

Although the participants in this study were at the AT center for an AAC evaluation, 66% (n = 35) reportedly relied on their natural speech to communicate. Eighty-eight percent (n = 47) were being prescribed their first AAC device. Eighty-seven percent (n = 46) of this sample currently had adequate motor abilities to access their devices via finger direct selection, 9% of the participants (n = 5) accessed their device via eye gaze,1 % (n = 1) accessed the device via switch, and 1% (n = 1) participant’s access method was yet to be determined.

The QUEST 2.0 survey was given to participants at their initial evaluation appointment to determine the device features and/or services participants identify as most important. 30 of the 53 participants responded to the QUEST 2.0 survey (refer to Figure 1). The questions on the QUEST survey considered satisfaction with the overall assistive technology device (questions 1 through 8) and satisfaction with the services of the intervention (questions 9 through 12). The final question on the survey asks the participants to identify which 3 of the 12 given parameters of satisfaction they deem to be the most important. Five participants completed the entire survey, three participants completed the majority of the survey (although within each section they may have left a couple of questions in the satisfaction with device or satisfaction with services sections unanswered). The QUEST survey assumes the individual has experience with the device and is not a first-time user. Because the majority of participants were first-time device users, only five complete QUEST surveys were available. Therefore, for this study, we focused on what variables participants identify as most important. Twenty-five of the 30 participants identified “easy to use” as an item of most importance, 15 identified effectiveness, 13 identified weight, 11 identified durability, and six identified dimensions and follow-up services as an item of most importance. Three participants identified comfort, adjustments, and repairs/servicing as an item of most importance. Only one participant identified service delivery as an item of most importance.

Figure 1. Percentage of patients who identified each of the following parameters as being of being the top most important.

Discussion

The purpose of this pilot study was to 1) identify and describe the population seeking AAC evaluations at an AT center in the Midwestern United States and 2) describe the features or services participants identify as most important at their initial AAC evaluations. This center provides AAC device prescription and intervention services for adults with acquired speech and communication disorders due to brain injury, spinal cord injury, stroke, and neurological complications as well as adults with developmental disabilities. As such, we predicted that the population being seen at this particular AT center would be diverse. Although a wide variety of individuals with acquired disabilities such as cerebrovascular accidents, ALS, progressive aphasia, and traumatic brain injuries require AAC (Lenker et al., 2005), the chart review revealed that, contrary to our predictions, the majority of patients seeking AT services at this particular AT center were diagnosed with progressive diseases.

It is important to note that although the majority of patients seeking evaluations at the AT center have progressive diseases, there were notable differences across these individuals. Twenty of the patients had a diagnosis of ALS, four had a diagnosis of Huntington’s disease, two had a diagnosis of primary progressive aphasia and the remaining two patients had diagnoses of Multiple Sclerosis and Parkinson’s disease. Although these are all progressive diseases, the progression and associated symptoms vary. Multiple Sclerosis – a central nervous disease that impacts the brain, spinal cord and optic nerves – follows four different disease courses (National MS Society, n.d.). Like Multiple Sclerosis, ALS is a nervous system disease that affects the brain and spinal cord. Although the signs and symptoms of ALS vary from person to person, disease the disease progression looks similar over time. The disease progresses until it eventually affects an individual’s control of the muscles needed to move, eat, speak and breathe (Mayo Clinic, n.d.). These examples illustrate how even when working with patient’s who fall under a general disease category (e.g., progressive diseases) the needs of each individual and progression of the disease may vary within and across disease type. As such, SLPs may not rely on a one-size-fits all approach to AAC device prescription or treatment.

Although we predicted that the AT center that served as the research site for this study would see a wide variety of patients because it is located in a large metropolitan area and accepts a wide range of funding sources to assist with AAC procurement, there are multiple reasons that the patient population being seen at this AT center is less diverse than we predicted. Firstly, it is possible that SLPs in the greater metropolitan area are, consistent with previous research (Fried-Oken et al., 2012), focusing on restoring their patient’s natural speech production. The finding that the majority of the patients seen at this center have progressive diseases may also be a reflection of the SLP’s relationships with different referral sources. It is estimated that 1 in 250 people in the United States are living with aphasia (NIDCD, 2015) and 5 in 100,000 people in the United States are living with ALS. Yet, 13% of the individuals in this research study had a diagnosis of aphasia and 37% had a diagnosis of ALS. This may be due to the fact that the SLP who provides AAC services at this AT center is also the SLP in a motor neuron disease clinic, enabling her to proactively educate providers (nurses, nurse practitioners, physicians, physician assistants) and patients about communication needs with disease progression and (consistent with current recommendations) prescribe AAC devices in anticipation of disease progression. Since AAC services are dependent on the referral sources, it may be that providers working with patients with non-progressive diseases are unaware of the services provided at this particular center. Future research should continue to work to identify which patient populations are accessing AT services, who is referring these individuals and what, if any, barriers may serve to prevent individuals from accessing services.

In addition to identifying and describing the population accessing AAC services at this AT center, we also sought to determine the features participants identify as most important at their initial AAC evaluations. To our knowledge, this is the first study to explicitly answer this question; previous research using the QUEST (Caligari et al., 2013; Ferriero et al., 2012) only reported device satisfaction. For the patients in this study, ease of use was rated as a most important feature by the highest percentage of individuals. This finding suggests that as participants trial different devices, clinicians should consider how intuitive a particular system is for that individual. After ease of use and effectiveness, weight and durability were both identified as important variables. The finding that weight was an important variable may be directly linked to participants’ characteristics. Thirty-two of the participants in this study were ambulatory, including those who reported difficulty or needing assistance with ambulation. For these participants, especially those who were reported to ambulate with difficulty, the weight of an AAC device may directly influence participants’ access to the device. If an AAC device is too heavy, the participant may choose not to carry it. This will subsequently limit their access, and, subsequently, overall use of the AAC device. This may, in turn, lead to device abandonment.

Unexpectedly, service delivery was an item of most importance for only one of the respondents. It is unclear why only one patient selected service delivery as one of the given parameters of satisfaction he or she deemed to be the most important. It is possible that participants expect to be able to learn to use the device effectively themselves with little to no training (hence the majority of participants indicating ease of use as a variable of most importance). If this is the case, it may be important for clinicians to educate people who require AAC about AAC service delivery and how the delivery may support learning to use the device and integration into daily life. More specifically, people who require AAC may be unaware of the online and phone support that exists from AAC device manufacturers because they did not yet need to use it. It is also possible that they do not have experience with AAC service delivery because they require AAC for the first time or they are comparing the service delivery models in AAC to consumer electronics service delivery. Ensuring that people who require AAC know when and how to reach out for support from manufacturers and service providers could reduce device abandonment. Finally, it is important to keep in mind that if an AAC device is difficult to use, difficult to transport (due to variables such as weight) and not effective, individuals may not fully adopt the AAC system. Moreover, these are most likely challenges that excellent service delivery will most likely may not be able to overcome and may result in device abandonment.

Study limitations

Although this study provides important information about patient characteristics and patient preferences in terms of AAC devices and services, the results should be interpreted cautiously. The finding that the majority of patients seeking treatment at this particular center have progressive diseases may be due to our use of random chart selection. It is possible that randomly selecting charts yielded a more homogenous population than is actually seen at the clinic. In addition, although we hypothesize that it is possible that the homogeneity observed in this sample may have been a due to the SLP having a relationship with practitioners in a motor neuron disease clinic may have resulted in increased referrals by this particular clinic, we did not directly collect this information. Future research should explicitly examine who is referring patients for AAC evaluations to determine whether there are differences in referral practices based on whether practitioners’ have relationships with SLPs to elucidate whether a lack of AAC knowledge is a referral barrier. Finally, these findings are from one AT center in a large metropolitan area in the Midwestern United States. In order to generalize these results, it will be important for additional studies to be conducted at other AT centers throughout the United States.

Clinical implications

Although indirect and at best preliminary in nature, the results from this study highlight the potential importance of SLPs developing strong relationships with clinics that serve individuals who may benefit from AAC. As such, SLPs should work to foster these relationships and educate practitioners who work with individuals who may benefit from AAC about the benefits of AAC with the hope that this education may decrease barriers to AAC access. The results from the QUEST survey serves to emphasize how critical it is for clinicians to consider how intuitive a particular system is for an individual. Moreover, these findings indicate that the physical properties of the device (i.e., weight and durability) are of utmost importance for ambulatory AAC consumers. As such, it may be important to have patients walk around with the device to ensure that the weight is appropriate and research device durability prior to recommending a particular device.

Conclusions

This study found that the majority of individuals being served at this AT center were diagnosed from progressive diseases rather than the diverse set of individuals we predicted would be accessing these services. This finding highlights the importance of determining who is accessing AAC services in other AT centers to determine if everyone who could benefit from AAC and is interested in trialing AAC devices has access to these services or whether barriers to AAC services exist. For the individuals being seen at this center, ease of use, effectiveness, and weight were the three parameters of satisfaction they deemed to be the most important. Future research should continue to determine who is accessing AAC services and, if specific patient populations are not accessing services, what are the barriers to accessing AAC services. In addition, researchers should continue to explore what patient-specific variables influence the successful implementation of AAC devices and services.

Acknowledgments

We would like to acknowledge Peyton Galbreath for assistance with editing and formatting the manuscript. We would also like to acknowledge the Assistive Technology Center at The Ohio State University Wexner Medical Center for their ongoing support of outcome measures in clinical practice.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research did not receive any funding.