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Augmentative and Alternative Communication

ISSN: 0743-4618 (Print) 1477-3848 (Online) Journal homepage: https://www.tandfonline.com/loi/iaac20

Using eye-tracking technology for communication in Rett syndrome: perceptions of impact

Kelli Vessoyan, Gill Steckle, Barb Easton, Megan Nichols, Victoria Mok Siu & Janette McDougall

To cite this article: Kelli Vessoyan, Gill Steckle, Barb Easton, Megan Nichols, Victoria Mok Siu & Janette McDougall (2018) Using eye-tracking technology for communication in Rett syndrome: perceptions of impact, Augmentative and Alternative Communication, 34:3, 230-241, DOI: 10.1080/07434618.2018.1462848

To link to this article: https://doi.org/10.1080/07434618.2018.1462848

Published online: 27 Apr 2018.

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RESEARCH ARTICLE

Using eye-tracking technology for communication in Rett syndrome: perceptions of impact

Kelli Vessoyana, Gill Stecklea, Barb Eastona, Megan Nicholsb, Victoria Mok Siuc and Janette McDougallb

aAugmentative Communication Service, Thames Valley Children’s Centre, London, Ontario, Canada; bResearch Department, Thames Valley Children’s Centre, London, Ontario, Canada; cMedical Genetics, London Health Sciences Centre, London, Ontario, Canada

ABSTRACT Studies have investigated the use of eye-tracking technology to assess cognition in individuals with Rett syndrome, but few have looked at this access method for communication for this group. Loss of speech, decreased hand use, and severe motor apraxia significantly impact functional communication for this population. Eye gaze is one modality that may be used successfully by individuals with Rett syndrome. This multiple case study explored whether using eye-tracking technology, with ongoing support from a team of augmentative and alternative communication (AAC) therapists, could help four participants with Rett syndrome meet individualized communication goals. Two secondary objectives were to examine parents' perspectives on (a) the psychosocial impact of their child’s use of the tech- nology, and (b) satisfaction with using the technology. All four participants were rated by the treating therapists to have made improvement on their goals. According to both quantitative findings and descriptive information, eye-tracking technology was viewed by parents as contributing to participants’ improved psychosocial functioning. Parents reported being highly satisfied with both the device and the clinical services received. This study provides initial evidence that eye-tracking may be perceived as a worthwhile and potentially satisfactory technology to support individuals with Rett syndrome in com- municating. Future, more rigorous research that addresses the limitations of a case study design is required to substantiate study findings.

ARTICLE HISTORY Received 16 June 2017 Revised 27 March 2018 Accepted 5 April 2018

KEYWORDS Rett syndrome; eye-tracking technology; communication goals; psychosocial impact; satisfaction

Introduction

Rett syndrome, first described by Andreas Rett 50 years ago (Ronen & Rosenbaum, 2016), is a severe, genetically based neurodevelopmental disorder that occurs in approximately 1 in 10,000–15,000 females (Fehr et al., 2011; Rose et al., 2013). In the majority of cases, it is caused by mutations in the MECP2 gene, which normally contributes to synaptic devel- opment and function and is necessary for learning and mem- ory (Amir et al., 1999; Baptista, Mercadante, Macedo, & Schwartzman, 2006; Rose et al., 2013). The disorder is charac- terized by an initial period of typical development, followed by four stages of disease progression. The first stage sees a slowing of development and begins between the ages of 6 and 18 months. In Stage 2, the regression stage, there is a decline in communication, language, and motor skills. Stereotypic hand movements and apraxia also begin to appear during this stage. Apraxia is the inability to plan and carry out a motor response and is often the most debilitating characteristic (Hunter, 2007), significantly impacting speech and manual dexterity. In Stage 3, the pseudostationary, or plateau, stage, difficulties with apraxia continue; however, there may be improvement in communication and motor skills. Stage 3 presentation may persist into the adult years. At 10 years of age or older, Stage 4 may begin, characterized

by increased rigidity, decreased mobility, and for some, a decrease in repetitive hand movements (Bartolotta, Zipp, Simpkins, & Glazewski, 2011; Hagberg, 2002; Lee, Leonard, Piek, & Downs, 2013). With syndrome progression, loss of speech and decreased functional hand use necessitate exploration of alternate communication methods.

According to Byiers and Symons (2013), early clinical lit- erature on Rett syndrome described those affected as having severe to profound intellectual impairment. It has been acknowledged more recently that apraxia and inability to speak would have interfered with effective participation in cognitive assessments and so earlier studies may have failed to give a true picture of cognitive abilities (Byiers & Symons, 2013). Researchers in the field are still working to find an unbiased, accessible way to assess the cognition of individu- als with this condition (Byiers & Symons, 2013).

Recent research indicates that individuals with Rett syn- drome are able to use a range of modalities to communicate with familiar partners. To investigate perceptions of commu- nication abilities, Bartolotta et al. (2011) examined survey responses from 141 parents, teachers, and speech-language pathologists who were all related to, or familiar with, individ- uals with Rett syndrome. Many modes of communication were perceived as important, including eye gaze, vocaliza- tions, body movements, gestures, and augmentative

CONTACT Kelli Vessoyan [email protected] Augmentative Communication Service, Thames Valley Children’s Centre, 779 Baseline Road East, London, Ontario N6C 5Y6, Canada ! 2018 International Society for Augmentative and Alternative Communication

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION 2018, VOL. 34, NO. 3, 230–241 https://doi.org/10.1080/07434618.2018.1462848

communication systems (pictures or graphic symbols), with eye gaze being the most frequently reported access tech- nique. They also found that familiar communication partners who interacted with these individuals on a regular basis were able to identify and describe communication acts that were perceived to be intentional. Often, considerable familiarity with the person communicating and the presumption of competence were required in order to identify and assign meaning to communication attempts (Bartolotta et al., 2011). In a study by Urbanowitz, Leonard, Girdler, Ciccone, and Downs (2016), 15 mothers reported that their daughters with Rett syndrome used expressive communication for a variety of reasons, including expressing discomfort or displeasure, making choices, requesting wanted items or activities, gaining attention, engaging socially, and expressing feelings. Parents and familiar partners often recognize these existing communication abilities. Finding a more reliable way for communication to be understood by all partners is imperative.

Over the last decade, studies have investigated the use of eye-tracking technology to assess cognition in individuals with Rett syndrome (Baptista et al., 2006; Rose et al., 2013). A recent systematic review concluded that the main purpose of most studies has been to substantiate cognitive abilities (Hirano & Taniguchi, 2015). Research using this technology provided the first empirical evidence that participants with Rett syndrome used eye gaze intentionally and could respond consistently to simple instructions and carry out simple cognitive tasks, such as matching and categorizing pictures (Baptista et al., 2006). Later studies using eye-tracking technology continued to focus on cognition. For example, Djukic and McDermott (2012) found that the participants in their study tended to exhibit a prefer- ence for social stimuli over objects, and Rose and colleagues (2013) established that at least some participants showed recognition of faces and patterns. It has been suggested that eye-tracking technology is a powerful tool for uncovering the potential and hidden cognitive abilities of those with Rett syndrome and for helping to improve their quality of life (Baptista et al., 2006; Hirano & Taniguchi, 2015).

Eye gaze is increasingly being promoted as a method that individuals with Rett syndrome can use to access communi- cation software (Bartolotta et al., 2011; Lariviere, 2015). In a survey of 64 speech-language pathologists in Sweden, 38% included computers with eye-gaze access in their interven- tion and reported that this worked well compared to other high-technology devices (Wandin, Lindberg, & Sonnander, 2015). Increased awareness of the capabilities of individuals who have Rett syndrome, and exploration of alternative ways to access symbolic communication, have resulted in more interest in the use of eye gaze as an access system for inten- tional communication.

Eye-tracking technologies use a person’s eye movements to control mouse functions on a computer. The eye-tracking device projects a low level of infrared light, and a camera on the system captures the angle of the reflection coming back from the user's eye(s) (Wilkinson & Mitchell, 2014). This deter- mines where the user’s gaze is positioned on the computer screen and orients the mouse cursor accordingly. When the user moves his or her eyes around the computer screen, the

cursor moves correspondingly. The eye-tracking system can be set so that when the user holds his or her gaze on a desired location for a specific length of dwell time (e.g., 1 s), a mouse click is activated. The dwell time must be short enough for the user to hold his or her gaze on the desired target, yet long enough to avoid accidental activations. Use of this technology is becoming more commonplace in aug- mentative and alternative communication (AAC) because it offers a more efficient direct-access method of communica- tion for individuals who are unable to use their hands. Such technology may not be accessible to all families or ser- vice providers.

A survey-based study examined families’ perspectives on their children with Rett syndrome’s use of eye-tracking tech- nology to access AAC (Townend et al., 2016). Researchers reported that 10 of the 11 families felt they had seen pro- gress in their child’s awareness, engagement, expressiveness, and understanding of language since using the communica- tion technology. These families indicated high satisfaction with professional support during the initial trial but expressed frustration with lack of ongoing support and with the technology itself. Another study examined the impact of eye-tracking technology intervention on the individualized goals related to daily activities for 10 participants with severe physical impairments without speaking abilities over time, and assessed family satisfaction with the services and the devices (Borgestig, Sandqvist, Ahlsten, Falkmer, & Hemmingsson, 2017b). Each of the participants attained their goals during and post-intervention, and parents’ satisfaction with both the device and services was high.

To date, there has been limited research involving the use of eye-tracking technology by individuals with Rett syndrome specifically for access to communication and to meet com- munication goals. There is also a need to examine whether these individuals continue to enhance their communication abilities over time using eye-tracking technology (Hirano & Taniguchi, 2015). In addition, it would be valuable to better understand the psychosocial impact of and parent satisfac- tion with the use of this technology. Such knowledge could inform decision making when considering use of eye-tracking technology for communication.

The purpose of this study was to explore how the partici- pants with Rett syndrome could use eye-tracking technology for communication purposes. The primary objective was to assess whether using this technology, with ongoing support from a team of AAC therapists, could help them meet indi- vidualized goals related to communication. Two secondary objectives were to examine parents’ perspectives on (a) the psychosocial impact on the participants of using the technol- ogy, and (b) satisfaction with using the technology.

Method

Design

This study used a multiple case study design (Thomas, 2011) for the following reasons: (a) Rett syndrome is a very rare condition, limiting the number of participants who could be recruited, and (b) the participants had been using the eye-

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION 231

tracking technology for varying lengths of time at the incep- tion of the study, therefore, a multiple baseline design was not feasible. Ethics approval was obtained through Western University Health Science Research Ethics Board.

Participants

The participants were children and youth with Rett syndrome receiving services from an AAC clinic in a children’s rehabili- tation center in Ontario, Canada, and their mothers. Participation was offered to the six families of clients with Rett syndrome who were on the AAC team caseload and were using eye-tracking technology at the time of recruit- ment. Four families consented to take part. Each mother- daughter dyad was present during all study visits. The clinical team consisted of a speech-language pathologist and one of two occupational therapists, all with over 20 years’ experi- ence assisting children with complex communication needs to use AAC.

At the beginning of the study, the participants were between 9- and 15-years-old and were at Stage 3 of Rett syn- drome. All four parents classified their daughters to be at Level IV (inconsistent sender and/or receiver of communica- tion with familiar partners) on the Communication Function Classification System (CFCS) (Hidecker et al., 2011). The CFCS classifies everyday communicative functioning on a 5-level categorical scale, with Level I representing the highest level of communicative functioning, and Level V the lowest. The CFCS demonstrates acceptable reliability and validity levels when completed by parents in relation to children with dis- abilities aged 4 years and older (Hidecker et al., 2011).

The participants in the current study had used a number of communication modes prior to receiving eye-tracking technology, including eye gaze to objects and pictures, body language, moving to a wanted item, and vocalizations (see Table 1 for details). They had been referred to the AAC clinic because these existing modes of communication were not meeting their communication needs, even with familiar partners, consistent with Level IV of the CFCS. All received an assessment of existing communication strengths and needs, following the service delivery pathway for the AAC clinic. As a result of this assessment, it was determined that eye-tracking technology would be an appropriate method to access a speech-generating device (SGD) with dynamic dis- play (TobiiTM1 SGD with either Communicator 4TM (See foot- note 1) or Grid 2TM2 symbol-based communication software). The communication pages on each SGD were individually customized with between eight and 30 locations per page. The display layout varied depending on the size, number of locations, and the area of the screen the person using the system was able to access easily. At the onset of the study participants had been using eye-tracking technology for between 2 and 14 months, and they and their families had

received training in the use of this technology through their involvement with the AAC service.

Measures

Goal Attainment Scaling. Goal Attainment Scaling (GAS) (Kiresuk, Smith, & Cardillo, 1994) was used to develop unique communication goals in the home and to assess progress after a specified intervention period. A primary strength of GAS is its ability to measure change in performance on goals (King, McDougall, Palisano, Gritzan, & Tucker, 1999). It has a 5-point scale, ranging from !2 (typically baseline level) to þ2 (much more than expected outcome) with 0 representing the expected (targeted) level of attainment after intervention. The aim is to have clinically equal intervals between all levels. Being criterion-referenced, goal attainment scaling is poten- tially responsive to small changes that are perceived by cli- ents and families as important for daily function. When carefully implemented, inter-rater reliability between two independent raters assessing goals on the same occasion can be very high (intraclass correlation coefficient ¼ 0.98) (King et al., 1999).

Psychosocial Impact of Assistive Devices Scale. To examine the psychosocial impact of the eye-tracking technology on study participants, the Psychosocial Impact of Assistive Devices Scale (PIADS) (Jutai & Day, 2002) was used. This scale is a 26-item measure that uses a 7-point scale ranging from !3 to þ3. Negative numbers allow for recording of any negative impact the technology may have. The PIADS has been shown to have good-to-excellent psychometric proper- ties (Jutai & Day, 2002). Principal Component Analysis (PCA) identifies three subscales that explain 61.1% of variance: competence, adaptability, and self-esteem (Day & Jutai, 1996). Internal consistency of the scale is high, a ¼ 0.95 for the total score and 0.92, 0.88, and 0.87 for subscales; t-tests (p values from 0.77 to 0.85) indicate scale stability.

Quebec User Evaluation of Satisfaction with Assistive Technology. The Quebec User Evaluation of Satisfaction with Assistive Technology Version 2 (QUEST 2.0) (Demers, Weiss- Lambrou, & Ska, 2002) was employed to evaluate parents’ satisfaction with the eye-tracking technology. This 12-item measure uses a 5-point Likert scale ranging from 1 (not satis- fied at all) to 5 (very satisfied) to evaluate satisfaction. It includes two factors: one about aspects of satisfaction with the device, such as ease of use and effectiveness for meeting needs, and one about satisfaction with services, such as repairs and follow-up services. Psychometric properties of the QUEST 2.0 are good (Demers et al., 2002). Cronbachs’ alpha for the total QUEST is 0.82, and 0.80 and 0.76 for subscales. Statistics indicate stability (Kappas from 0.51 to 0.74) and PCA yields a two-factor solution (48.4% of variance) (Demers, Weiss-Lambrou, & Ska, 2000).

Other tools. The research team developed a Clinical Observation Form for the therapists to record observations during study visits and to assist them later in scoring the attainment of goals. It included information about the home environment, the participants’ health, technical issues, and observed activities and interactions. Three other study-

1Tobii and Communicator 4 are products of Tobii DynaVox, part of the Tobii Group (Tobii AB), Karlsrov€agen 2D, Sweden. www.tobiidynavox.com 2Grid 2 is a product of Smartbox Assistive Technology, Malvern, England. www.thinksmartbox.com

232 K. VESSOYAN ET AL.

specific tools were developed to collect additional descriptive information from parents regarding factors contributing to device use, families’ satisfaction with the eye-tracking tech- nology, and psychosocial impact of device use on study par- ticipants. The Background Information Form included questions about demographics, symptoms related to Rett syndrome, health issues, and communication. The research team also created a Parent Semi-Structured Interview form to obtain information regarding device use and the parents’ perceptions about the eye-tracking technology. Finally, a Parent Observation Diary was designed for parents to cap- ture interactions, levels of prompting, and anecdotal informa- tion about their daughter’s use of the communication technology outside of study visits.

Procedures

Participants were active clients of the occupational therapists and speech-language pathologist members of the research team. Services provided at the AAC clinic are family-driven and needs-based and therefore vary between clients. Services may include assessment, training and supporting family and school teams with functional and operational use of the tech- nology, supporting other aided and unaided AAC strategies, and responding to technical issues. Therapists incorporated these services as needed into the study visits described in the sections that follow and team members were also avail- able between study visits if parents identified additional intervention needs.

The therapists contacted families by telephone to intro- duce the study. Families interested in learning more were mailed a letter of information, an informed consent form,

and a stamped self-addressed envelope. To avoid undue influence for families to participate, a research assistant com- pleted the informed consent process. The assistant also con- tacted the interested parents by telephone within a week to discuss the study and the letter of information, and to answer any questions. The research assistant ensured that parents understood that they were not obligated to partici- pate and could withdraw from the study at any time without impact on the ongoing services they were receiving from the AAC clinic. Parents signed a form providing consent for both themselves and their children.

A therapist contacted parents when the signed consent form was received, to set up the first of five visits with each participant. Together, an occupational therapist and the speech-language pathologist completed these visits in the family home. The overall duration of the study was 12 months. At Visits 2–5, the therapists video recorded the participants using their eye-tracking technology to commu- nicate with a parent for later review. The recording time was defined by how long the participants remained engaged in the interaction. The recordings lasted between 6 and 53 min with a mean length of 27.4 min. One video camera recorded selections made on the Tobii and another recorded the face of the individual using eye-tracking to help interpret intentionality of message selection (e.g., whether they appeared to be looking at the selected mes- sage when it was spoken).

Visit 1. Parents completed the background information form and identified the level on the CFCS that they felt matched their daughter’s communication performance. The parents completed the Psychosocial Impact of Assistive Devices Scale (PIADS) (Jutai & Day, 2002) and shared chal- lenges and areas for improvement with respect to using the

Table 1. Participant communication characteristics.

Participant Age at onset of study

Technology use prior to study (in months)

Significant communication partners Communication modes prior to eye gaze technology

1 15 13 Immediate family Approaches person and touches to get attention Extended family (occasionally) Indicates “yes” by winking her eye School team Indicates “no” by turning her head away Peers and buddies Uses eye pointing to select pictures on a frame Respite workers Asks to go on swing by standing at the door

Indicates “thirsty” by standing at the sink Walks to a desired item

2 15 14 Family Walks up to people if she wants to talk Extended family Yeh indicates wanting to engage in conversation Peers at school Indicates “yes” by looking straight at a person Teachers Indicates “no” by looking down Educational assistants Indicates desire to eat by standing at end of the table Personal support workers

Community helpers Indicates basic needs and choices via eye pointing to up to

four objects, pictures, symbols, or text Special services at home Looks at partner’s verbally labeled hands to make choice

3 9 4 Family Vocalizes to get attention Peers Reaches for items Educational assistants Eye pointing to objects or pictures

Walks with a wanted item Signs MORE, ALL DONE Step-by-StepTMa

4 10 2 Family Squawking Extended family Eye gaze to objects Teachers Picture symbol book via eye gaze or partner assisted Bus driver BIG Step-by-StepTMa (e.g., for book reading)

Details on communication partners and communication modes from background information form. aStep-by-Step and BIG Step-by-Step are products of AbleNet Inc., Roseville, MN, USA. www.ablenetinc.com

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION 233

eye-tracking technology. Through discussion, parents and therapists reviewed each participant’s existing communica- tion skills, identified areas of desired improvement, and col- laboratively established two new communication goals for the study. Collaborative goal setting helps to ensure the goals are meaningful to the child and family (King et al., 1999). All parents selected one goal to extend their daughter’s reasons for communicating, targeting communica- tion functions (e.g., asking questions, commenting) that they were not using. The second goal for each participant varied but included initiating interactions with others, increasing length of novel utterances, and navigating between commu- nication pages on their device. See Table 2 for the specific goals. Attainment of these goals was set as level 0 on GAS.

Following a family-centered service delivery model (Law et al., 2003), parents and therapists agreed on the perceived baseline level of performance for each participant. Rather than collecting baseline data, the parents described the exist- ing communication performance for each goal, and this level of performance was categorized as the baseline (–2). Parents were asked to consider a realistic time frame for their child to reach the expected outcome (0). All selected a 6-month time frame for both goals. The therapists scaled the goals and consulted with a researcher trained in GAS to ensure the levels met the specific requirements. Parents worked on the goals with the participants at home. It was anticipated that it might be difficult to directly observe goal attainment during subsequent visits that were to be video recorded. It was therefore suggested that, between study visits, the parent observation diary be completed for any 10-min period, once a week. The therapists described how to collect information about the use of the eye-tracking technology in the diary. They also consulted with the parents regarding potential strategies to promote communication (e.g., assuming compe- tence, following their daughter’s lead, acknowledging, and assigning meaning to communication attempts) and help the participants meet their goals.

Visit 2. After 6 months, the same two therapists who had completed Visit 1 re-visited the home for goal review. They recorded videos of the study participants using their eye- tracking technology. The QUEST 2.0 was left for the parents to complete confidentially. The parents completed the PIADS a second time. Following this visit, both therapists observed the videos together, completed the clinical observation form, and scored the goals. The two therapists together scored the goals of three participants. To assess inter-rater reliability, they scored the goals of the fourth participant separately and there was 100% agreement between therapists on these goals. To further assess inter-rater reliability, a randomly selected goal for each participant was independently rated by a non-treating therapist (i.e., not part of the clinical research team) and compared to the rating provided by the two therapists on the clinical team. This approach has been used to assess inter-rater reliability in past research using GAS (King et al., 1999). It is recommended that an independ- ent rater be someone not involved in treatment or goal set- ting (Kiresuk et al., 1994), that is, the independent rater is blind to the established baseline and therefore will not be biased by this knowledge when making a follow-up

assessment. The role of the independent rater is not to assess improvement or lack of it, but rather to provide their perception of performance at a specific time point that can be compared to the original rater. There was 50% agreement between the therapists on the clinical team and the non- treating therapist on the scores for the four randomly selected goals.

Visit 3. Within 1 week of the second visit, the same two therapists again recorded a video of each participant using eye-tracking technology for communication. This allowed the therapists to account for day-to-day variations in perform- ance that can be evident for individuals with Rett syndrome (Bartolotta et al., 2011), as well as the possibility of other fac- tors affecting communication, such as pain, fatigue, environ- mental distractions, and technology breakdown. Each participant’s performance on their GAS goals at either the second or third visit that was deemed by the parent and therapists to be closest to their typical abilities was used as the follow-up score. The sealed envelope containing the completed QUEST 2.0 was collected by the therapists and delivered directly to the research assistant for analysis. At the end of the visit, parents completed a semi-structured inter- view with one of the therapists.

Visits 4 and 5. Communication interactions were video recorded again at Visit 4 (3 months after Visit 3) and Visit 5 (a further 3 months later). This was done to assess goal main- tenance over time. The same therapists then viewed the vid- eos, completed the clinical observation form, and scored the goals.

Data analysis

The GAS scores were analyzed for progress and maintenance. Therapists used the clinical observation form to count instan- ces of communication related to an identified goal. For example, if the goal was to increase communicative func- tions, the therapists tallied each observed function during the video recording to score the goal on the scale. If the time described in the scaling was for a period longer than the video recording (e.g., 3 to 4 times daily), therapists asked parents about the level of the goal parents thought had been attained. As with collaborative goal setting, obtaining input on ratings from parents is valid because both are based on a consensus involving individuals who are know- ledgeable about the child and invested in ensuring that the child makes real gains (King et al., 1999). Typically, achieving the expected level (0) on a GAS goal is considered successful goal attainment (Kiresuk et al., 1994); however, even small changes in performance can be meaningful. A minimal clinic- ally important difference (MCID) represents the smallest change in a measure that is considered worthwhile (Iyer, Haley, Watkins, & Dumas, 2003). Clinicians can provide useful information about amount of change that is minimally important (Iyer et al., 2003). Therefore, an MCID was judged by the study team to be a 1-level change on the GAS scale.

The baseline and follow-up scores of the three domains (competence, adaptability, and self-esteem) of the PIADS were compared for each participant to see if using the eye-

234 K. VESSOYAN ET AL.

Table 2. Participant goals.

Participant Goals Score Scaling

1 Will select messages on her Tobii (See footnote 1) device for an increasing number of reasons

!2 P will occasionally use messages on the Tobii to request items or to share information (two functions).

!1 P will use an increasing number of communication functions on the Tobii when prompted within natural contexts throughout the day (two or more functions).

0 P will independently use an increasing number of communication functions on the Tobii, within natural contexts throughout the day (two to three functions).

1 P will independently use an increasing number of communication functions on the Tobii, within natural contexts throughout the day (four to five functions).

2 P will independently use an increasing number of communication functions on the Tobii, within natural contexts throughout the day (six or more functions).

Will initiate an interaction with others by selecting an appropriate message on the Tobii

!2 P will occasionally initiate an interaction with another person by standing close to them, or by moving to where the Tobii is situated.

!1 P will select a message on the Tobii when a familiar communication partner asks if she has something to share.

0 P will independently initiate an interaction with a familiar person by selecting a message on the Tobii once per day.

1 P will independently initiate an interaction with a familiar person by selecting a message on the Tobii 2 to 3 times per day.

2 P will independently initiate an interaction with a familiar person by selecting a message on the Tobii more than 3 times per day.

2 Will ask questions with increasing frequency !2 P will ask a question selected from the greetings page on the Tobii. (“How are you?”, “What’s new?”, and “What should we do?”) fewer than 2 times daily.

!1 P will ask a question selected from any page on the Tobii twice daily. 0 P will ask a question from any page on the Tobii 3 to 4 times daily. 1 P will ask a question from any page on the Tobii 5 to 6 times daily. 2 P will ask a question from any page on the Tobii more than 6 times daily.

Will increase the length of novel utterances by using two or more core words in a meaningful message

!2 P will select pre-stored phrases and sentences from a variety of pages on the Tobii.

!1 P will select individual words from a new page with core words on the Tobii to say a meaningful message.

0 P will combine two core words on the Tobii to say a meaningful message. 1 P will combine three core words on the Tobii to say a meaningful message. 2 P will combine four or more core words on the Tobii to say a meaning-

ful message. 3 Will combine two words together in a meaningful

utterance using the Tobii device !2 P will select single words from a variety of pages on the Tobii.

!1 P will sometimes (five or less times per day) combine two words on the Tobii in a meaningful utterance when prompted.

0 P will often (more than 5 times per day) combine two words on the Tobii in a meaningful utterance when prompted.

1 P will sometimes (5 or less times per day) combine two words on the Tobii in a meaningful utterance without prompting.

2 P will often (more than 5 times per day) combine two words on the Tobii in a meaningful utterance without prompting.

Will use words or phrases on the Tobii device to comment

!2 P will select words from a variety of pages on the Tobii to make requests only.

!1 P will sometimes comment (5 or less times per day) using the Tobii when prompted.

0 P will often (more than 5 times per day) comment using the Tobii when prompted.

1 P will sometimes comment (5 or less times per day) using the Tobii with- out prompting.

2 P will often (more than 5 times per day) comment using the Tobii with- out prompting.

4 Will navigate independently between familiar pages (both forward and backward) on the Tobii

!2 P will select a navigation button with eye gaze to move forward to another page. Communication partner uses navigation buttons to move back to previous or main page.

!1 P will move back one page using eye gaze with prompting from a facilitator. 0 P will move back one page independently using eye gaze. 1 Without prompting, P will move back more than one page using eye gaze. 2 P will use eye gaze to consistently select navigation buttons to independently

change pages, moving either forward or backward. Will communicate for an increasing number of rea-

sons (increased communicative functions) !2 P will independently use messages on the Tobii to request items (e.g., food),

talk about feelings and to comment in a structured activity. !1 P will use messages on the Tobii for communicative functions other than

what is listed above, with direct prompting from a communication partner. 0 P will independently use messages on the Tobii for more than three reasons

in a structured activity. 1 P will independently use messages on the Tobii for more than three reasons

in either a structured activity or spontaneously. 2 P will spontaneously use messages on the Tobii for more than three reasons.

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION 235

tracking technology led to any perceived change in psycho- social functioning. An MCID in any domain was judged by the study team to be represented by a 0.50 score change. Although this is a small difference on the scale, given the dif- ficulties that girls with Rett syndrome have with communica- tion, the team felt this interval difference could represent an important change.

Descriptive information from the parent semi-structured interview and the parent observation diary provided add- itional details considered to be related to the psychosocial impact of the eye-tracking technology on participants. The scores provided by each parent for the two components (Assistive Device and Services) of the QUEST 2.0, as well as the total score, were tallied and the average scores were cal- culated. The findings of this standardized measure were com- pared to what parents reported about the technology in the parent semi-structured interview.

Results

Goal attainment

Goal Attainment Scaling scores from each of the visits are pre- sented in Table 3. Communication interactions were deemed by parents and therapists to be typical during the second visit for all participants; therefore, it was not considered necessary to use performance on the third visit as the follow-up score. Three participants were perceived to have achieved a minimal clinically important difference (i.e., þ1) on both goals when

assessed by the therapists on their clinical team. Participant 1 exceeded expectations for both goals. Participant 2 met the expected level on one goal but not on the other, yet still achieved a minimal clinically important difference. Participant 3 met the expected level on one goal and exceeded expectation on the other. Participant 4 met the expected level on one goal but did not progress on the other. Ratings on the four ran- domly selected goals, scored by the non-treating therapist at the second visit, differed from the ratings of the therapists on the clinical team for two participants.

According to the therapist ratings, Participants 1, 2, and 3 continued to improve on their goals at Visit 4. At Visit 5, Participant 1 maintained improvement on both goals. Participants 2 and 3 maintained improvement on one goal and regressed one level on the other. Participant 4 continued to have no improvement on one goal at Visits 4 and 5, regressed to a less than expected level on her other goal at Visit 4, and returned to her baseline score at Visit 5.

Psychosocial impact

Participant 3 was perceived to have achieved a minimal clin- ically important difference on all three domains of the PIADS from Visit 1 to 2, in the areas of competence, adaptability, and self-esteem. The other participants were rated as having achieved a minimal clinically important difference on at least two of the domains at the second visit. See Table 4 for PIADS scores. The number of parent observation diary entries over the course of the study varied between families (i.e., 5, 17, 34, and 37 total entries). The findings indicate an overall positive psychosocial impact of using the eye-tracking technology. One parent talked about learning more about her daughter’s interests, commenting that she was able to “share about [the] day at school.” Another reported that with the device, her daughter was “more engaged,” and another said that her daughter felt “a sense of empow- erment” related to being able to make autonomous deci- sions. Table 5 includes findings from the parent interviews and observation diaries.

Parents’ satisfaction with technology and service

All four parents rated their satisfaction at either 4 (quite satis- fied) or 5 (very satisfied) for both the eye-tracking technology

Table 3. Goal Attainment Scaling results for participants across time.

Visit 1 (baseline) Visit 2a (6 months after

first visit) Visit 2b (6 months after

first visit) Visit 4 (3 months after

second visit) Visit 5 (6 months after

second visit)

Goal 1 Participant 1 !2 1 1 2 2 Participant 2 !2 0 0 1 0 Participant 3 !2 0 — 2 1 Participant 4 !2 !2 0 !2 !2

Goal 2 Participant 1 !2 1 — 2 2 Participant 2 !2 !1 — 0 0 Participant 3 !2 1 2 2 2 Participant 4 !2 0 — !1 !2

Minimal clinically important difference represented by 1-level change. aSecond visit scores were used (as opposed to third visit scores) for all participants since performance at second visit was deemed typical of communication ability for all participants. bScores for randomly selected goals scored by non-treating therapist.

Table 4. PIADS results: psychosocial impact of eye-tracking technology.

Participant Sub-domain Visit 1 Visit 2 Increase

1 Competence 1.33 2.00 0.67 Adaptability 0.83 1.67 0.84 Self-esteem 1.88 1.75 !0.13

2 Competence 1.50 2.00 0.50 Adaptability 1.83 1.17 !0.66 Self-esteem 1.13 2.25 1.12

3 Competence 1.00 2.17 1.17 Adaptability 0.83 2.00 1.17 Self-esteem 0.88 1.50 0.62

4 Competence 0.67 1.25 0.58 Adaptability 0.50 1.83 1.33 Self-esteem 0.88 1.25 0.37

PIADS: Psychosocial Impact of Assistive Devices Scale. The PIADS sub-domain scales range from !3 to þ3. For the purposes of this study, an increase of 0.50 from baseline to follow-up was considered clinically meaningful.

236 K. VESSOYAN ET AL.

and services, with somewhat greater satisfaction indicated for services. The QUEST 2.0 average scores across the four parents were 4.47 out of 5 (range: 4.00 to 4.88) for satisfaction with the assistive device, 4.88 out of 5 (range: 4.75–5.00) for satisfaction with services, and 4.63 out of 5 (range: 4.38–4.83) for total sat- isfaction. When asked what aspects of service were most important to them, all parents chose ease of device use. Other areas of importance included device effectiveness, professional services, follow-up services, and device durability. Parent com- ments provided at the third visit reflected what they felt to be the biggest benefits and disadvantages of using a device accessed via eye-tracking technology. Parents also commented on changes they would like to see with respect to the device and its use, as well as factors contributing to their daughters’ success. See Table 6 for details.

Discussion

Individuals with Rett syndrome have more to say than they are able to express using speech and other natural modes of communication. Advances in technology have opened up avenues for access to language via eye gaze, which is noted as a strength for many of these individuals. There is still little documented evidence to support this access method for aided communication, and it remains unattainable for many families due to cost and limited availability. Due to limita- tions in the design of this study, the evidence that the partic- ipants were able to use eye-tracking technology to help meet their communication goals is preliminary and tentative. Likewise, the study design limits any inference about whether participants were able to maintain, or continue to improve, their performance on individualized goals. Although

Table 5. Communication and psychological adjustment: parent interview and observation diary comments.

Question Parent comments

What can your daughter communicate now that she couldn’t before receiving the device?

“So many things. Food/activity choices, tell how she’s feeling, say what’s wrong, share photo albums and videos, choose own music and videos, share about day at school, keyboard, letters of alphabet, commenting.”

“Participates in conversations. Can say when she wants a break.” “More specific needs e.g., something hurts – now identifies what hurts.” “Can ask for what she needs e.g., arm braces. Will ask for her headphones if it’s

too noisy.” “Expresses emotions: able to say ‘thank you’ or ‘I love you.’ ” “Giving opinion, making statements, asking questions.”

What is different now since receiving the device? “Sense of empowerment, listening to her, acknowledging her, positive sense of control.”

“Feels more empowered because gets what she wants (attention, objects, needs fulfilled).”

“Found out that she has a sense of humor.” “Very appropriate with her comments.” “Less frustration. She is more content/satisfied to say feelings.” “Has improved peer relationships. Helps with inclusion.”

Has your daughter said anything using her device that has surprised you? Please describe.

“‘I love you.’ Commenting about her brother, ‘He is cool.’ ” “Says things that express personality (e.g., ‘I don’t like that noise.’)” “Crying – thought she would say something hurts and she said ‘Thank you’, ‘I

love you.’ ” “Shows she is following the conversation.” “Emotions/humor.”

What difference do you think it would make to your daughter and your family if the device were no longer available?

“Huge difference – like her voice was taken away from her.” “It would be a little lonely.” “Family has learned more about communication systems. Would find it

difficult.” “Big difference. Challenge.”

Is there anything noteworthy/remarkable/exciting that happened while your daughter was using her device today?

“Went over to Tobii1 independently told us ‘something’s wrong’, ‘I’m cold’ 3 times, and was shivering; we wrapped her up with a blanket at table and she smiled about this.”

“Independently asked me ‘What did you do today?’ on chat page.” “Independently said ‘What I did at school’, ‘smart board’ and ‘music’ accurate

according to class notes.” “Brother came home while she was writing and she picked ‘L’ and insisted (by

‘yes’ smiles) the word was love” “More engaged than usual – sustained interest. Enjoyed the game of taking

turns writing words.” “We introduced pages this week and she is very excited about all the new

options. She’s experimenting a lot – most interested in different faces.” “Independently to chat page and ‘Tell you what I did at school’; choices

matched communication book news of day.” “Independently to keyboard; independently chose letter “m” assisted facilitation

of spelling m-o-m.” “Was experimenting with core words on her own and talking a lot when alone

in her room.” “Face lit up when she realized she could ask to ‘snuggle’ – great big smile.” “Facilitated going to activities page as she was standing at back door asking to

go out; She independently chose ‘Outside’ and ‘Go out on deck’. Independently ‘Tell you what I think’, ‘I like this’, ‘Can we do it again?’, ‘I like it when you talk to me.’ ”

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION 237

there was perceived improvement on the agreed goals, the procedures for collecting baseline data were different to the procedures at subsequent visits and there is a risk that rater bias may have influenced goal attainment rating. It cannot be definitively stated that there was actual goal attainment. Nevertheless, a perception of change in communicative abil- ity is important, even if unsupported by clear or robust evi- dence of measurable change, as it can bring about higher expectations and provide motivation for communication part- ners to increase their engagement with individuals with sig- nificant communication difficulties (Borgestig, Rytterstr€om, & Hemmingsson, 2017a). In turn, this may result in more com- munication opportunities and the ongoing further develop- ment of communication skills (Borgestig et al., 2017a).

When describing participant communication abilities at the beginning of the study, parents identified a limited num- ber of communication modes that were used, including eye gaze to objects, pictures or symbols, body language, and vocalizations. In a study assessing forms and functions of pre- linguistic behaviors for 120 children and adults with Rett syn- drome, Didden and colleagues (Didden et al., 2010) found that the majority used prelinguistic communicative behaviors, with eye gaze identified as the most common form. Symbolic forms of communication were rarely used. Familiar communi- cation partners may be able to interpret the basic intent of a person’s communication when these unaided modes are used, but not the specific content expressed. For example, an individual may gaze at a door to indicate a desire to go somewhere but there may not be a way to convey where. Unfamiliar communication partners may not be attentive to the eye gaze or aware of how specific body movements or vocalizations may reflect message intent.

The use of eye-tracking technology to access vocabulary that could be used for a greater range of communication

purposes and understood by a wider audience may take indi- viduals with Rett syndrome one step closer to autonomous communication: “Being able to say whatever I want to say, to whoever I want to say it to, whenever I want to say it” (Porter & Burkhart, 2012). Parents in the current study reported that since receiving the device, their daughters were able to communicate to achieve a wider range of func- tions than they could before, for example, to make choices, share opinions, and express needs and emotions. In addition, peer and other family relationships were said to have improved. Although these changes cannot be attributed to the introduction of eye-tracking technology, parents’ percep- tions of such improvements are still important.

Quantitative data based on the parent reports suggest that the eye-tracking technology may have had a positive effect on at least two of the psychosocial domains for each participant. These findings were supported by the parents’ descriptive comments, which indicated that they perceived a positive influence of the device on psychosocial functioning of participants. Parents expressed now being able to get to know their daughters’ needs, feelings, and interests. While these reports and views may be valid, it must be noted that they may also have been influenced to some extent by parents’ investment in the study or by a desire to maintain good relationships with the clinical members of the research team. It is interesting to note that although one participant achieved the expected outcome on only one of her goals by Visit 2 and no measurable goal attainment over time, the family still indicated that they were highly satisfied with her use of the device. For example, this family reported that peo- ple outside of the home commented on how well their daughter was able to interact using the technology. Clinically, although individuals may not be meeting all of their goals in specific areas, it is important to look at their

Table 6. Device use: parent interview comments.

Question Response

What is the biggest benefit of having the device up to this point? “To give her a voice or a say, empowering and valuing her” “Getting to know daughter and her personality” “Able to hear more of her specific thoughts” “Progressed in education with it, very helpful at school”

What contributes to your daughter’s ability to use the device successfully? “Participating in a preferred activity” “A favorite communication partner” “Being well-rested” “Receiving prompts to use the device” “Motivation, music, mood” “No technical issues” “Good health” “Decreased pressure and increased emotional connection”

Have there been any disadvantages to having the device? Please describe. “Not portable, can't use it in other venues” “Not practical due to physical set up” “Not being able to train with everyone” “Can’t take it anywhere; not usable in all situations”

If there was one thing you could change about the device, what would it be? “Make access with eye gaze more efficient” “Voices (i.e., little girl’s voice)” “More portable (thinner and lighter)” “Have apps on the device” “Response time, not as fluid as it is meant to be”

If there was one thing you could change about how your daughter uses the device, what would it be?

“Feels tedious sometimes – if not reliably/consistently picking up eye gaze, wish she could choose letters and spell on keyboard”

“To be able to use it more independently – not having to have Mom bring device but maybe walk up to it to use it”

“More responsive, so that she could have more of a conversation”

238 K. VESSOYAN ET AL.

functioning within the context of the family and social envi- ronments outside of the home (Batorowicz, Campbell, von Tetzchner, King, & Missiuna, 2014).

There are several possible explanations for the perception that one individual had such limited success in meeting her goals. These may include that she had not had her device as long as the other participants, and therefore had not yet developed some of the basic skills required for communica- tion success. It may have been that the goals were too diffi- cult, that interest was not sustained on the goals, or perhaps, that the ratings were less reliable for this participant at or subsequent to baseline. The study design did not collect spe- cific information from families that might have provided insights as to why goal attainment may not have been achieved as expected. Future studies may focus on factors limiting goal attainment.

Parental satisfaction

Borgestig et al. (2017b) talk about the importance of satisfac- tion with respect to sustained use of technology over time. All parents in the current study reported being highly satis- fied with both the eye-tracking technology and the related service they received from the AAC team, indicating that they may continue to support the use of the eye-tracking in the future. With respect to the communication technology, families reported that ease of use, effectiveness, and durabil- ity were particularly important, as were professional and fol- low-up services. The one other study that has reported on satisfaction with services related to the use of eye-tracking technology with individuals who have Rett syndrome found that parents would have liked more hands-on and intensive support over a longer time period (Townend et al., 2016). These researchers concluded that greater input from know- ledgeable AAC professionals was essential in order for indi- viduals and their families to maximally benefit from using the eye-gaze technology for communication. The AAC team in the current study was available to consult with families on an as-needed basis over the 12 months of the study, and families reported being most satisfied with services delivered in this manner. It is possible that this service-delivery approach could have resulted in the same gains, regardless of the mode of communication being used. What seems important to note is that this intervention, including both the services delivered and technology provided, was highly valued by the families. This satisfaction alone may account for their positive perception of change.

Borgestig et al. (2017a) noted that families learned more about their children’s personalities, sense of humor, and feel- ings toward other people through their use of gaze-based assistive technology. Similarly, in the current study, parents described some of the biggest benefits of using the technol- ogy as “getting to know [daughter] and her personality” and being “able to hear more of her specific thoughts.” See Table 6 for more parent comments. Personal and environ- mental factors identified by parents as contributing to these successes included motivation, consciousness (i.e., being well-rested), mood, health, and familiar and attentive

communication partners. These factors were identified in another study as influencing communication abilities using modalities other than eye tracking (Baptista et al., 2006). Prompting from communication partners was also seen as an important factor contributing to success, although all parents reported observing initiation of communication by their daughters.

Disadvantages of the device included lack of portability, accessibility, and responsiveness. Many newer eye-tracking technologies are peripheral or integrated into smaller devices that can be used across more environments. Communication software and overall computer processing is also constantly being improved. These enhancements to eye-tracking tech- nology can only serve to increase access to communication opportunities for those with Rett syndrome.

Limitations

The perceived improvement on the goals might be related to a number of factors, including that eye gaze is a strength for individuals with Rett syndrome and that eye tracking cap- italizes on this natural ability. Goals were set in collaboration with the families, who knew the participant’s preferences and their communication opportunities throughout the day, potentially contributing to establishment of highly meaning- ful and motivating goals. However, a major limitation of this study is that the treating therapists were also involved as researchers and had existing ongoing clinical relationships with the families. This may have introduced significant pres- sure on families to participate and unduly influenced their responses on study measures and in interviews. Despite assurances that non-participation and the nature of their responses would not impact the provision of regular clinical services, it is not possible to determine to what extent this relationship affected findings.

It must also be acknowledged that there is a significant risk that goal rating may have been biased in favor of improvement due to the dual roles played by the therapists in this study and their relationship with families. It is typically recommended that the therapist who sets the levels for goal attainment should not be the one involved with the client, yet it is acknowledged that this is difficult to maintain in a clinical setting (King et al., 1999). Treating therapists being involved in setting the goal levels is defensible when a researcher with expertise in GAS is involved in the review of the goal attainment levels but an independent therapist rates the goals (King et al., 1999). In order to measure goal attain- ment reliably, baseline and subsequent ratings should be established in the same manner. In this study, reliability could have been improved if the baseline had been set by reviewing the videos and talking to parents, as happened in later visits.

There were also differences in how the treating and non- treating therapists were able to rate the goals, given that non-treating therapists only viewed the videos. Additionally, there was only 50% agreement between the therapists pro- viding clinical services and the non-treating therapist on per- formance of one randomly selected goal, at one point in

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION 239

time, for each participant. On the two goals where there was no agreement, the non-treating therapist rated goal attain- ment higher. The fact that the therapists on the clinical team scored the goals lower may indicate that they had been overly careful in trying to avoid bias by under-estimating goal ratings and so inadvertently introduced reverse bias. Differences between therapists’ scores on two goals could have also been influenced by the fact that the treating thera- pists made observations directly in the home environment and may have been sensitive to environmental influences on the interaction (e.g., cueing). These therapists were also able to confirm ratings after consulting with parents on their per- ceptions. These and other reasons for lack of agreement across raters remain speculative.

Future studies involving individuals with Rett syndrome should take into account what has been learned in this study regarding goal scaling and scoring. It has been suggested that goals are more likely to be attained when they are set by the person who is working toward the goal and are there- fore intrinsically motivating (Borgestig et al., 2017b). In this study, because the participants had limited communication skills, goals were set collaboratively by parents and thera- pists. These goals may not have been important to the par- ticipants, which may have affected their engagement.

Another limitation was that the participants had already been using eye-tracking technology for varying periods of time at the start of the study. Those who had been using a device longer and were potentially more skilled in its use may have had a better chance of attaining their goals. All of the goals set at the beginning of the study were new goals that had not previously been worked on, thus, they were all starting from the same place in terms of individualized goals.

The descriptive information gathered from the parent dia- ries that appeared to support goal attainment scores was subjective in nature; however, this information was based on direct observations, not retrospective recall. In addition, par- ent perspectives are considered by researchers in the field to be integral to assessing communicative abilities and inform- ing interventions for individuals with Rett syndrome (Ronen & Rosenbaum, 2016; Urbanowitz et al., 2016). Given that parents are invested in their children’s lives and in them making real progress, it could be argued that such invest- ment might decrease the possibility of biased responses.

Conclusion

It is imperative to obtain more evidence related to communi- cation strategies that work best for individuals with Rett syn- drome. To the authors’ knowledge, this is the first study to explore individualized goal attainment related to communica- tion outcomes for individuals with Rett syndrome using eye- tracking technology, over a specified period of time. It is also the first study to document the psychosocial impact of using this technology with this population, and one of the first to examine parents’ satisfaction with the use of eye-tracking technology to access communication. All four participants were rated by the treating therapists as having made improvements on communication goals. Although this

cannot be considered objective evidence of change, there was perceived change that extended beyond targeted study outcomes. These perceptions remained regardless of whether the technology made measurable differences to communica- tion goals. In addition, quantitative data and descriptive comments from parents suggest that they perceived that eye-tracking technology had a positive impact on their daughters’ competence, adaptability, and self-esteem. Overall, parents reported being satisfied with both the technology and the services they received related to the eye-tracking technology. Future more rigorous research that addresses issues of bias is required to build on this prelimin- ary work and to continue to open the world of communica- tion for individuals with Rett syndrome.

Disclosure statement

No potential conflict of interest was reported by the authors.

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