The Reliability of a Three-point Emoji Scale in the Assessment of the Increase of Symptomology in a Group of People Aging with Cerebral Palsy—A Preliminary Study
Kajiyama, Brian, M.Ed., Mahiko, Joy, Ph.D., Dantzig, Stephen A., Psy.D., Nishida, John
United Cerebral Palsy Association of Hawai’i
ABSTRACT
The present paper presents the rationale and reliability of using emojis as part of a longer-term study examining the perceived impacts of aging on people with cerebral palsy. There is increasing evidence that while the brain lesion that caused cerebral palsy is not progressive, “Its musculoskeletal manifestations are progressive due to the long-term effects of spasticity on the musculoskeletal system. (Katsma, et. al, 2024)” There is clearly a humanitarian need to continue to research the effects of, and potential interventions, for those who are aging with cerebral palsy. There may also be a financial benefit if the level of care is narrowed down to be more effective and streamlined. The efficacy of using emojis to assist people with disabilities communicate how they feel as well as the validity of limiting a Likert-type scale to three choices for those with disabilities is discussed. The long-term study intends to use three emojis paired with three descriptions of how people may experience the effects of aging with cerebral palsy in a series of surveys. The current study presented the three emojis to the general public and sought an association between the pictograms and the choice of effects offered. While the number of useful responses were limited (n=24), the results indicated a high correlation between the chosen emojis and the associated feelings. Eleven responses were excluded because the respondents chose the same emoji for two or all three choices. The results validate the use of the chosen emojis to assist in the administration of surveys designed to assess the impact of aging with cerebral palsy despite the number of invalid responses. Implications for future research is discussed.
INTRODUCTION
The present paper presents the rationale and reliability of using emojis as part of a longer-term study examining the perceived impacts of aging on people with cerebral palsy. There is increasing evidence that while the brain lesion that caused cerebral palsy is not progressive, “Its musculoskeletal manifestations are progressive due to the long-term effects of spasticity on the musculoskeletal system. (Katsma, et. al, 2024)” The long-term goals of these series of studies are:
- Locate people who live in Hawai’i who are aging with cerebral palsy in order to provide community resources and services as needed;
- Gather information from these people about their perception of how their bodies and abilities have changed, or are changing as they age and what resources they need for assistance;
- Use the data to investigate the availability of, or feasible establishment of the resources needed.
The project will involve the use of a survey or set of surveys designed by this research team, based generally on the results of previous research but primarily based on the personal and professional experience of the researchers. The main survey has been broken down into seven components to be prioritized and administered in shorter segments and/or to establish follow-up studies. The seven components are: physical changes; communication changes; pain changes; changes in adaptive functioning; access to and satisfaction with medical/mental health services; current concerns; and need for resources. There is evidence of the valid use of emojis to assist respondents who may have difficulty with purely language-based surveys (Davies, et. al, 2022). They a state: “The studies reported here provide robust initial evidence for the use of a short emoji-based tool with minimal literacy requirements for the measurement of a range of psychosocial domains including aspects of mental health, well-being, community connection and resilience. The brevity and ease of use of this tool is likely to make it of particular interest for use in non-clinical settings, especially where measuring the service impact on participants/attendees is an ancillary focus.” It is the viewpoint of the authors that the inclusion of emojis may assist the eventual respondents to provide reliable and valid responses to our questions. The current phase of the study seeks to establish a reliable correspondence between the emojis chosen and the verbal/written response choices.
Britannica.com defines “emoji” as digital pictograms used widely in online (text, email, social media, etc.) designed to quickly identify human emotions and other characteristics. “The term emoji was born from two Japanese words: e, meaning “picture,” and moji, meaning “’written character.’” They are meant to quickly communicate thoughts and emotions quickly through a non-verbal medium. The use of emojis in digital communication has exploded. “Findings show over 90% of online users employ emoji, with more than 70 billion sent daily. (George, George, and Baskar, 2023).” Furthermore, “Users highlight emoji’s ability to convey emotion and nuance non-verbally across language barriers. The visual nature of emoji facilitates universal understanding not achievable through text alone. Analysis shows over 80% of users believe emoji effectively communicate thoughts and feelings internationally. (Ibid, 2023)” Ceraratti-Bertin (2024) quotes Scott J. Varda, Ph.D. of Baylor University, stating that approximately 92% of online communicators use emojis daily and that “’Emojis do convey basic ideas, but ‘they also include abstract ideas or emotions,’ Varda said.”
Robinson (2020) states that emojis have found their way into the normally stoic realm of business communications: “The 2019 Emoji Trend Report was released last month, and the results are in: 61% of employees use emojis at work. The report said that emojis help users better communicate their thoughts and feelings and connect to people they routinely text or online message.” Furthermore: “Vik Verma, CEO of unified communications platform company 8×8, encourages the use of emojis in workplace communications. He told me, ‘Plain and simple, emojis help employees communicate more effectively with each other. They can indicate tone that might otherwise be misconstrued and can boost credibility. What’s really important is getting your message across as clearly as possible, and if emojis can help with that, then go right ahead.’”
Of particular interest to the long-term study is Robinson’s comment that: “More companies are looking at new technological advancements that can help alleviate cognitive overload, compassion fatigue and employee burnout.” Fatigue is a factor with our projected population: A common statistic quoted online is: “People with CP use three to five times the energy of people without the disorder to complete everyday tasks (https://www.healthline.com/health/adult-cerebral-palsy#premature-aging). The result is a significant increase in spasticity, ataxia, athetosis, pain, social isolation, depression, anxiety, etc. (Holland, 2018)”
The use of emoji with people with disabilities
Effective communication can be difficult for all of us. It can be more complicated for people with disabilities. Emojis might help. Walker (2025) states: “In an increasingly digital world, communication has evolved beyond traditional text-based interactions. Messaging platforms, social media, and online forums rely on text as the primary medium, yet text alone often fails to convey emotions, tone, or intent effectively. This can lead to misinterpretations, misunderstandings, and difficulties in social interactions. The use of symbols like the laughing emoji has become essential in digital conversations, helping users clarify tone and express humor in a way that plain text cannot.
For individuals with disabilities, especially those with speech impairments, cognitive challenges, or autism spectrum disorder (ASD), expressing emotions and thoughts through text can be even more complex.”
“Many individuals face barriers to verbal and written communication. People with speech impairments, ASD, or cognitive disabilities often find it difficult to convey emotions, intent, or reactions through traditional text. This can lead to social isolation and frustration.”
Many people with cerebral palsy face additional difficulties, even in the absence of comorbid intellectual disability. Flint Rehab notes “Non-verbal cerebral palsy is caused by severe dysarthria, which describes difficulties controlling the muscles necessary to speak.” It is the often-repeated opinion of the researchers that speech and language are two different things (Dantzig, Fentiman and Duris, 2002 and 2018). “Language” is the sharing of thoughts and ideas via a system of symbols that a particular society agrees upon (hence the many different ways to express ideas seen throughout the world.) A symbol for an idea can be a spoken word, a written word, a sign in sign language, a gesture, a picture, or now, an emoji.
Flint Rehab continues: “About 25% of individuals with cerebral palsy are non-verbal. However, that does not mean they don’t have anything to say or are incapable of understanding what you say to them…Many people with non-verbal cerebral palsy can fully understand what you say to them and know exactly what they want to say back but are unable to because they cannot control their oral muscles.” Pictures, or emojis, may assist in communication.
Concerns:
There are several concerns related to a survey type of study that are addressed in the research design of this study. The first has to do with the nature of surveys or non-standardized surveys in general. Likert Scales are often used for psycho-social scales such as assessments that measure anxiety (Sattler, et. al., 2001). Likert scales, like the ones that will be used in the future study, ask respondents to rate whatever is assessed according to ratings that place values on how they feel. An example would be the Beck Depression Inventory-II (Beck, et. al. 1996). One of the drawbacks to a Likert scale is the distance between “points” are not consistent or standardized: Each respondent may interpret the “points” differently: what does a “3” on a scale of anxiety mean for each respondent? (Sattler, et. al., 2001).
Moreover, Hartley and MacLean (2006) reviewed the literature on the use of Likert Scales with respondents with intellectual disabilities. They caution that: “Low response rates were found among adolescents and adults with moderate to profound ID, when pictorial representations of response alternatives were not employed, and for Likert-type scales with self-descriptive statements…This does not mean that 5-point Likert scales are most advantageous for people with ID…response alternatives should correspond to respondents’ actual experiences, and fewer response alternatives may more closely parallel those experiences (Chang, 1994).”
Regarding emojis, George, George and Baskar (2023), caution that while young people who have grown up in the digital era prefer the use of emojis over written text alone, “Generational divides exist, where older demographics may not comprehend emoji meanings as intuitively.” Ceraratti-Bertin (2024) further quotes Dr. Varda as saying: “As a rhetorician, each new emoji offers the promise of better conveying meaning, more strongly explaining argument and more accurately capturing emotion, but also risks misunderstanding,” Varda said. “It’s similar to each new word added to a language. The increasing range of emojis is a simultaneous cause for excitement and caution.”
There are also visual concerns to consider when using pictograms to study the experience of people aging with cerebral palsy. Kiger (no date) quotes Galli J, Loi E, Molinaro A, Calza S, Franzoni A, Micheletti S, Rossi A, Semeraro F, Fazzi E (2022): “One in every ten children with Cerebral Palsy (CP) presents with severe visual impairment and 75-90% present with some degree of visual impairment.”
Di Maci (2023) states that: “In the instance of sight impairments, the World Health Organization (WHO) estimates that at least 2.2 billion people have a near or distance vision impairment, across the world. The majority of people with vision impairment and blindness are over the age of 50 years (old age here we all come), however, vision loss affects people of all ages.” Di Maci continues that many blind or people with visual disabilities often rely on assistive technology such as screen readers to “read” text. The concern is: “A screen reader translates an image’s meaning via its alt text, and emojis are also ‘read’ through a type of alt text – the Unicode string – which represents each emoji. Screen readers interpret the Unicode character string used by browsers and operating systems, to understand and display emojis.” The example given was two different emojis that look different but represent the idea “fine.” The screen reader interprets the emojis differently. The final concern is that the distinction between emojis can be difficult to distinguish for people with perfect vision, let alone people with visual disabilities.
Research Design
The long-term goal of this project is to study if and how people experience the impact of aging with cerebral palsy. The survey items were designed to assess the perceived differences in the participant’s experiences over specified time frames. A sample question might be: “Are you experiencing more pain now than you did five years ago?” The cautions of Sattler (2001), Hartley and MacLean (2006), and DiMaci (2023) were considered when developing the surveys. The initial draft of the surveys included five response options. This initial format was rejected in favor of a three-point scale because: the differences between points on a Likert scale may be greater and clearer across three points rather than five points. The potential cognitive and fatigue concerns of our population may be better addressed with less response options. The visual distinctions between three emojis are clearer than between five choices. Emojis were chosen to represent the emotions expressed by the three response choices.
The overall objective of the main study is to assess the personal viewpoints of the impact of aging with cerebral palsy on our respondents. The surveys were designed to assess the perceived functioning and compare it to the perception of past functioning. As such, the main study will allow for “interviewers to paraphrase and/or expand upon question items or response alternatives” which is “related to an increased response rate and decreased response bias among adolescents and adults with ID (Hartley and MacLean, 2006).” The fatigue and cognitive factors (Dantzig, 2012) inherent with cerebral palsy were also considered so pictograms (emoji) were included to assist respondents to provide valid and reliable responses to the survey questions.
The “generational gap” (George, George and Baskar, 2023) was addressed by presenting the current survey to the staff of the United Cerebral Palsy Association of Hawai’i, parents of the children served by the United Cerebral Palsy Association of Hawai’i, and broadly on popular Social Media outlets such as LinkedIn and Facebook.
The goal of this phase of the current research is to study how reliably the three chosen emojis correspond to the text of the survey written/verbal response choices among the general population. All of the concerns noted have been accounted for in the research design for this study.
Methodology and Design:
The survey was offered online as a fillable Google Forms. Respondents were recruited via five avenues: students of some of the authors, staff and Board Members of the United Cerebral Palsy Association of Hawai’i, other non-profit organizations that serve people with disabilities in Hawai’i, and through links to the Google Forms version posted on Facebook and LinkedIn and the UCPA Hawai’i website. The “other” means of recruitment were direct email requests and information posted on the United Cerebral Palsy Association of Hawai’i website. Responses were requested from May 2, 2025, through May 20, 2025. Requests for participation were posted on Facebook and LinkedIn five times. Fellow non-profit organizations as well as staff and Board Members of UCPA Hawai’i were sent links to the survey via email. College students of two of the researchers were also given the link to the survey. Friends and family of one of the researchers (Dantzig) were sent direct emails with the link to the survey.
The main study proposes to assess the degree to which aging with cerebral palsy impacted the lives of the respondents. The current study offered one question as a sample of the main surveys. Data on gender (male, female and unspecified) were also requested. Data on general age rages (20-39 years, 40-50 years, over 60 years and unspecified) were requested in order to address the question of age differences in the interpretation of emojis (George, George and Baskar, 2023 and Ceraratti-Bertin, 2024). Gender and/or age differences were analyzed. Demographic data were requested, but responses were optional.
Emoji Survey to Help in a Future Project About Aging with Cerebral Palsy
Aloha!
We need your help to validate the emojis for a future survey on how people with cerebral palsy view life as they age. Emojis might help our future participants accurately communicate how they feel. A sample question might be about increasing pain levels. Your feedback will help ensure that participants can accurately match emojis to their experiences. Mahalo!
Informed Consent
This survey will take about five minutes. There is no risk to you if you participate and no personal identifiable information will be collected. Questions about your gender and age range are optional.
___ Yes*
___ No**
* Sample Future Survey Question 1
For example, a question might be: “Are you experiencing more pain than you were five years ago?”
Which emoji (1, 2, or 3) best represents the term sometimes?
1 😀 2 😐 3😭
__1
__2
__3
For example, a question might be: “Are you experiencing more pain than you were five years ago?”
Which emoji (1, 2, or 3) best represents the term not at all?
1 😀 2 😐 3😭
__1
__2
__3
For example, a question might be: “Are you experiencing more pain than you were five years ago?”
Which emoji (1, 2, or 3) best represents the term almost all of the time?
1 😀 2 😐 3😭
__1
__2
__3
Demographics
You may choose not to respond to the following questions, but your responses will help us to understand the results.
Gender:
___ Male
___ Female
___ Prefer not to say
Age Range:
___ 20-39
___ 40-59
___ 60 and over
How did you hear of this survey?
___ College Student
___ Employee or Board Member of the United Cerebral Palsy Association of Hawai’i
___ Social Media
___ Member of a different non-profit organization in Hawai’i
___ Other
** Declined to Participate
Thank you for your time. You may hit “submit” now or simply close your browser.
It was predicted that each choice would obtain a Pearson Reliability Coefficient of .9 or better.
Results:
All responses were completely anonymous. A total of 35 responses were obtained. Eleven responses, or 31 per cent of the total responses, were eliminated because the same emoji was chosen for two or all three choices available. Data from the 24 “valid” responses were analyzed.
| Category | # of Total | % of Total |
Chose 😐 correctly
|
Chose 😁 correctly
|
Chose 😭 correctly
|
| All Respondents | 35 | 100 | 86% | 74% | 74% |
| Respondents who chose same emoji for more than one option (deleted from analysis) | 11 | 31 | |||
| “Clean-no duplicates” (Basis for analysis) | 24 | 69 | 96% | 100% | 96% |
Table A
| Category | # of Total | % of Total |
Chose 😐 correctly
|
Chose 😁 correctly
|
Chose 😭 correctly
|
|
| “Clean-no duplicates” (Basis for analysis) | 24 | 69 | 96% | 100% | 96% | |
| Female | 19 | 79 | 95% | 100% | 95% | |
| Male | 5 | 21 | 100% | 100% | 100% | |
| Age 20-39 | 5 | 21 | 80% | 100% | 80% | |
| Age 40-59 | 7 | 29 | 100% | 100% | 100% | |
| Age 60 and + | 11 | 46 | 100% | 100% | 100% | |
| Age prefer not to tell | 1 | 4 | 100% | 100% | 100% | |
| College Student | 5 | 21 | 80 | 100 | 80 | |
| UCPA Hawai’i | 11 | 46 | 100% | 100% | 100% | |
| Different non-profit | 4 | 17 | 100% | 100% | 100% | |
| Other | 3 | 13 | 100% | 100% | 100% | |
| Social Media | 1 | 4 | 100% | 100% | 100% | |
Table B
Seventy-nine per cent of the valid responses came from females, while twenty-one per cent came from males. One respondent chose not to reply to gender but was excluded for choosing the same emoji for two response options. Twenty-one per cent of the respondents fell in the age range of 20 to 39 years of age; twenty-nine per cent fell in the age range of 40 to years of age and forty-nine percent were reportedly 60 years of age or older. One respondent, or four percent of the usable sample, chose not to respond to the question of age. Twenty-one percent of usable responses came from college students, forty-six percent came from UCPA Hawai’i, seventeen per cent came from other non-profit organizations in Hawai’i, thirteen per cent were from other sources and four per cent of the responses were gathered from social media.
Data discarded due to duplicate responses to choices
| Category | Number of Total | % of Total | % of Discarded Data | 2 of same response (number) | 3 of same response (number) |
| All | 11 | 31 | 100 | 6 | 5 |
| Female | 3 | 9 | 27 | 1 | 2 |
| Male | 7 | 20 | 64 | 4 | 3 |
| Other Gender | 1 | 3 | 9 | 1 | |
| Age 20-39 | 2 | 6 | 18 | 1 | 1 |
| Age 40-59 | 3 | 9 | 27 | 1 | 2 |
| Age 60 and + | 4 | 11 | 36 | 2 | 2 |
| No Age | 2 | 6 | 18 | 1 | 1 |
| College Student | 0 | 0 | 0 | 0 | 0 |
| UCPA Hawai’i | 1 | 3 | 9 | 1 | |
| Other Non-profit | 4 | 11 | 36 | 2 | 2 |
| Other | 4 | 11 | 36 | 2 | 2 |
| Social Media | 2 | 6 | 18 | 2 |
Table C
Sixty-four per cent of the invalid responses came from males, twenty-seven per cent came from males and nine per cent chose not to respond. Eighteen per cent of the respondents fell in the age range of 20 to 39 years of age; Twenty-nine per cent fell in the age range of 40 to years of age, thirty-six per cent were reportedly 60 years of age or older, and eighteen per cent chose not to respond to the question of age. None of the invalid responses came from college students, nine per cent came from UCPA Hawai’i, thity-six per cent came from other non-profit organizations in Hawai’i, thirty-six per cent were from other sources and eighteen per cent of the responses were gathered from social media.
| Emoji | 😀 Chosen twice | 😀 Chosen three times | 😐 Chosen twice | 😐 Chosen three times | 😭 Chosen twice | 😭 Chosen three times |
| Total | 0 | 1 | 4 | 4 | 1 | 1 |
| Male | 0 | 1 | 2 | 2 | 1 | 1 |
| Female | 0 | 0 | 2 | 2 | 0 | 0 |
| Other | 0 | 0 | 1 | 0 | 0 | 0 |
| Age 20-39 | 0 | 0 | 1 | 1 | 0 | 0 |
| Age 40-59 | 0 | 0 | 1 | 3 | 0 | 1 |
| Age 60 and + | 0 | 0 | 1 | 1 | 1 | 0 |
| No age | 0 | 0 | 1 | 0 | 0 | 0 |
| UCP | 0 | 0 | 0 | 0 | 1 | 0 |
| Other Non-profit | 0 | 0 | 3 | 0 | 0 | 1 |
| Other | 0 | 0 | 2 | 2 | 0 | 0 |
| Social Media | 0 | 1 | 0 | 1 | 0 | 0 |
Table D
Data were invalidated for the following reasons:
😀 was chosen for all three responses on one occasion.
😐 was chosen for all three responses on four occasions
😐 was chosen for two responses on four occasions.
😭 was chosen for all three responses on one occasion.
😭 was chosen for two responses on one occasion.
The breakdown of invalid responses is detailed in Figure C.
Analysis of valid data:
Twenty-three out of the twenty-four valid responses were correct.
The emoji 😐 was chosen to represent “I feel more pain than five years ago” sometimes ninety-six percent of the time.
The emoji 😁 was chosen to represent “I feel more pain than five years go” not at all one hundred percent of the time.
The emoji 😭 was chosen to represent “I feel more pain than five years go” not at all one hundred percent of the time.
The breakdown of the percentages of correct responses by category is presented in Table A. The only disparate data came from one error from a college student from the age range of 20-39 years.
Discussion:
Despite the limited number of valid respondents, the results presented represent robust and compelling data to support the use of the chosen emojis for use in collaboration with the written or verbal descriptions of the feelings associated with the increase in symptomology that may be experienced by people aging with cerebral palsy. The example question chosen for this study was: “Are you experiencing more pain now than five years ago?” The emojis chosen were, by design, not associated with the written or verbal responses that will be offered in the actual survey. Feedback from some respondents indicated that the way the questions were presented were confusing. The authors acknowledge that and feel that pairing the emojis with the written/verbal responses will effectively alleviate that ambiguity.
One potential concern that was presented to one of the examiners (Dantzig) by a colleague was the choice of the “sobbing” (😭) emoji to represent an increase in pain “almost all of the time.” It was noted that the meaning of emojis is changing and evolving all of the time and the “sobbing” emoji has been used recently to express joy (personal communication, Dantzig, 2025). The data did not indicate this as a concern. The one “valid error” was not a juxtaposition of the sobbing emoji with the smiling emoji.
Concerns: This study did highlight some concerns that need to be addressed in future studies. The per cent of responses with emojis chosen for multiple responses presented a major concern. Future studies need to explicitly state to choose one option.
Authors:
Brian Kajiyama, MA, University of Hawai’i at Manoa
Joy Mahiko, Ph.D., University of Hawai’i, West O’ahu
Stephen A. Dantzig, Psy.D., Rutgers University Graduate School of Applied and Professional Psychology (Graduate, not employed)
John Nishida, Executive Director, United Cerebral Palsy Association of Hawai’i
Conflict of interest:
Stephen A. Dantzig and Brian Kajiyama are both aging with cerebral palsy. John Nishida is the Executive Director of the United Cerebral Palsy Association of Hawai’i. However, no conflict of interests exists in this study.
Funding:
References:
Beck, A. T., Steer, R. A., & Brown, G. (1996). Beck Depression Inventory–II (BDI-II) [Database record]. APA PsycTests, https://www.britannica.com/topic/emoji
Cefaratti-Bertin, Shelby, More Than Just a Smiley Face: How Emojis Can Affect Communication, July 17, 2024, https://news.web.baylor.edu/news/story/2024/more-just-smiley-face-how-emojis-can-affect-communication
Dantzig, Stephen, Fentiman, Jean, Duris, Michael, A Guide to the Theory, Administration and Interpretation of the Southern California Ordinal Scales of Development: Scales of Cognition, 2002, Stephen Dantzig Educational Consulting Service.
Dantzig, Stephen, Get Up, Your Bus is Here: Living MY life with Cerebral Palsy Trials, Tribulation and Triumphs, 2012, Stephen Dantzig Educational Consulting Services.
Dantzig, Stephen, Fentiman, Jean, Duris, Michael, A Guide to the Theory, Administration and Interpretation of the Southern California Ordinal Scales of Development: Scales of Cognition Second Edition, 2018, Stephen Dantzig Educational Consulting Service.
Davies, Jason, McKenna, Mark, Denner, Kate, Bayley, Jon and Morgan, Matthew The emoji current mood and experience scale: the development and initial validation of an ultra-brief, literacy independent measure of psychological health, Journal of Mental Health, 2022, 218-226.
Di Mace, June 27th, 2023, Do emojis and accessibility work together?
https://www.tiny.cloud/blog/emojis-and-accessibility/
George, A. Shaji, George, A.s. Havan, and Baskar, T., Dr., Emoji Unite: Examining the Rise of Emoji as an International Language Bridging Cultural and Generational Divides, Partners Universal International Innovation Journal (PUIIJ), https://www.researchgate.net/publication/373361579_Emoji_Unite_Examining_the_Rise_of_Emoji_as_an_International_Language_Bridging_Cultural_and_Generational_Divides, Volume: 01 Issue: 04 | July-August 2023 | www.puiij.com
Flint Rehab, Non-Verbal Cerebral Palsy and Alternative Forms of Communication, Medically reviewed by Elizabeth Denslow, OTR/L , Last updated on December 4, 2020, https://www.flintrehab.com/non-verbal-cerebral-palsy/
Galli J, Loi E, Molinaro A, Calza S, Franzoni A, Micheletti S, Rossi A, Semeraro F, Fazzi E, CP Collaborative Group. Age-related effects on the spectrum of cerebral visual impairment in children with cerebral palsy. Frontiers in human neuroscience. 2022 Mar 2;16:750464
Hartley, S.L. and MacLean, W.E., Jr., A Review of the reliability and validity of Likert-type scales for people with intellectual disability, Journal of Intellectual Disability Research, Volume 50, Part II, pp 813-827, November, 2006.
Holland, Kimberly, (medically reviewed by Sampson, Stacy, D.O), https://www.cerebralpalsy.org/about-cerebral-palsy/life-expectancy/life-span, 2018, https://www.healthline.com/health/adult-cerebral-palsy
Katsma, Mark, et. al., Management and treatment of musculoskeletal problems in adults with cerebral palsy: Experience gained from two lifespan clinics, J Pediatr Rehabil Med, 2024 Mar 26;17(1):19–33, https://pmc.ncbi.nlm.nih.gov/articles/PMC10977450/
Kiger, Angela, (no date), Vision Impairment in children with Cerebral Palsy, https://www.physio-pedia.com/Vision_Impairment_in_children_with_Cerebral_Palsy#cite_ref-1
Robinson, Bryan, Ph.D., Are Emojis Ruining Our Communication And Adding to Isolation From One Another?, https://community.thriveglobal.com/are-emojis-replacing-talking-about-feelings/, January 23, 2020.
Sattler, J. M. (2001). Assessment of children: Cognitive applications (4th ed.). Jerome M Sattler Publisher.
Walker, Lisa, How Emojis Help People With Disabilities Communicate, 8 March 2025, https://disabilitiesartsexualitiesconf.org/how-emojis-help-people-with-disabilities-communicate/