The P.E.A.C.E Scale

Creating a New Pain Management Scale for Autistic Children in Healthcare Facilities:

The Pain Expression and Communication Evaluation Scale (PEACE Scale)

Shashini Mohan

April 29, 2025

Introduction and Literature review 

Autism Spectrum Disorder (ASD) is characterized as a “heterogeneous neurodevelopmental disorder including challenges with social interaction, communication in various contexts, and the presence of repetitive, restricted patterns of behavior, activities, and interests”, according to the National Institute of Mental Health¹. These symptoms typically appear in early developmental stages and vary in severity between each individual child¹. The American Psychological Association characterizes autism by associating the disorder with difficulties in social communication and social interaction². Difficulties with social communication and interaction often lead to indirect impacts such as harassment or social exclusion, yet this is further exemplified in healthcare settings as they can present as an overwhelming environment³. 

Pain is a complex phenomenon that has sensory, emotional, and psychological dimensions associated with it. In children with Autism Spectrum Disorder, pain perception and communication are especially restrictive due to the presence of communicative difficulties in addition to intellectual difficulties. Despite the increasing awareness for mental disabilities, there still remains limited research specifically to pain management of ASD children. In most healthcare settings with autistic children, healthcare professionals are not properly trained to decipher their needs, which in turn leads to failure to completely understand the needs of the child as a whole³. Intervention is essential, as within a general population 1 in 100 individuals have ASD, yet our knowledge and understanding of the communicative needs of autistic children is quite minimal¹. A survey completed by healthcare providers studying the challenges associated with providing care for autistic children resulted in a mere 28.9 percent being able to identify the child’s clinical problem despite having communication or relationship difficulties³. In this study, Devico explains the perspective of healthcare professionals in regards to children with ASD and shows how an astonishing 31 percent of healthcare providers felt as if they could not communicate properly, and 100 percent agreed upon the need for additional help to communicate and manage the needs of autistic children³. 

Due to the complexities of Autism Spectrum Disorder, autistic children tend to have a higher sensitivity to pain⁴. However, there is still a major source of concern, regarding how children with this disorder feel and communicate pain as they have difficulties with communication⁴. Coined by Costello et al., communicative vulnerability refers to patients who have a reduced capability to communicate and express their feelings⁴. As these communication vulnerabilities can range from slight miscommunication to severe communication disabilities, in most cases healthcare professionals rely on parental judgment⁵. Historically however, children with ASD have been described as having a different response to painful stimuli especially in regards to reports in healthcare facilities described by Nader et al⁵. Nader explains how parents of autistic children underestimate their child's pain when using parent reporting, which is a commonly used method of pain communication with ASD children in healthcare facilities⁵. A consistent theme across literature associated with ASD in clinical settings is the discrepancy between parent pain reports and behavioral observations by healthcare providers, whereas neurotypical children show a positive correlation between the two⁵. Knoll et al. further explored how abnormalities within pain responses such as self harm, or withdrawal affected how autistic children express their pain levels, specifically highlighting how the heightened responses of anxiety to hospital settings may lead to under recognition of pain when self reporting is utilized⁶. Therefore, it is understood that pain is subjective, and as Twycross et al. puts it, only the patient can truly report how much pain they feel⁷. Twycross emphasizes the need for flexible and multi-modal scales to accommodate the variability with pain, and specifically for ASD children as a numerical score of 6/10 may be mild pain to one but severe pain for the other. Further, Elizabeth et al explains how children presenting with ASD demonstrate less outward reactions to pain due to their social communicative deficit¹². Yet throughout the treatment of autistic children in healthcare facilities the typically used method of pain evaluation is left to a child’s parent^6,7,8. But with an addition of abnormal behaviors and social communicative deficits which make it so that their pain may not be detected easily, it becomes incredibly difficult to understand the distress of autistic children potentially leading to further injury, psychological distress, or mistreatment, further exemplifying the need for self evaluations⁸.

Yet, it has been shown by multiple studies that pictorial images, such as the Picture Exchange Communication System (PECS) or the Wong- Baker Faces Scale (which are the faces commonly seen in all healthcare settings), can be used to facilitate communication^8,6. Currently, a widely used self reporting pain management scale used throughout the United States is the Wong Baker Faces Scale⁹. First created by Wong and Baker this scale shows six faces horizontally aligned with progressing facial expressions starting with bright green to red, a numerical scale from 0-10 and text phrases to describe hurt under each face (refer to Figure 5.)⁹. However, in studies conducted by Fitzpatrick et al. designed to understand the complexities associated with self reporting for autistic children Fitzpatrick asserts that the presence of the WBF alone was insufficient¹⁰. Elizabeth explains how pain scales that do not consider using literal language such as the WBF do not adequately meet the needs of children with autism spectrum disorder¹¹. Another major concern associated with the use of PECS or the Wong-Baker Faces Scale is that autistic children need more time to process questions, getting frustrated when that need is not met as they present as direct “orders” which they oppose¹². Traditional methods such as these may cause frustration and disobedient behavior due to their lack of adaptability¹, which further  highlights the need for a modified approach to communication tools. Specifically tools that are designed in a way that allow autistic children to feel as if they are in power to make their own decisions, use known communication strategies, and where predictability is able to be maintained. 

Figure 5. The Wong-Baker Faces Scale. A common pain evaluation tool used in pediatric evaluations

Identifying this major gap leads this research to create a revised pain management scale  that can be used by autistic children who are hospitalized. Doing so would allow for easier communication and treatment for autistic children, as well as an easier process for healthcare providers to track the emotions and behaviors of these children to reduce the amount of miscommunication and mistreatment within the healthcare facilities. 

Methodology

This study employs a qualitative approach through a creative inquiry methodology to design a revised pain management scale that is specifically tailored towards autistic children. Using secondary sources to develop and devise a scale, this study takes the successful components of existing pain management scales (specifically the Wong Baker Faces Scale)  making it a qualitative study. The purpose of this study is not to conduct experiments and collect empirical data, it is to synthesize literature from other works behind the use of the WBF pain management scale to inspire the creation of a more inclusive and accessible communication tool for autistic children in healthcare facilities. As this scale is used to evaluate the pain expression and communication for autistic children it will be given the name: PEACE Scale, which stands for Pain Expression and Communication Evaluation for Autistic children scale. 

The specific development of the Pain management scale can be broken down into 2 components: 

1. Breakdown of other pain management scales

2. Design and construction of the PEACE scale 

Analysis of other pain management scales

To inspire and revise previous pain management scales this study conducted an in-depth analysis of pediatric scales that are currently implemented in healthcare facilities in the United States, particularly focusing on the Wong Baker Faces Pain Rating Scale (WBF) which is currently the most commonly used pain management scale for children in clinical practice, therefore it was used in the deconstruction process in this study. To guide the breakdown of this scale, a qualitative content analysis was performed where the components of the WBF were analyzed to understand its structure, strategy, and visual components allowing a proper analysis of whether specific elements of the WBF were beneficial or harmful in response to autistic children.

A component was determined to be beneficial if it demonstrated alignment with autistic needs of:

1. Supporting clarity of communication

2. Minimizing sensory overload 

3. Using literal language that is not open to abstract interpretation

4. Allowing alternative communication methods 

A component will be deemed as harmful if it:

1. Relies on abstract concepts 

2. Uses exaggerated/ underwhelming emotions

3. Includes overstimulation colors

4. Requires further verbal cues for understanding

Design and construction of the PEACE scale

The scale was designed using the graphic design platform Canva, and was scaled to fit a standard US letter sized page, measuring 8 inches in width and 11 inches in height with a portrait focus on the body diagram and faces. The page layout consisted of three separations of design: a centrally placed body diagram with two columns of faces on the left and right sides that represent varying levels of pain intensity. Each design element was spaced equidistant and symmetrical to minimize visual clutter with the top and bottom margins being around 1 inch to create a cleaner buffer between the title and figure content. The central body diagram measured approximately 2.8 inches wide and 7.9 inches tall, occupying the central quadrant of the product. The silhouette was a rendered image from Canva’s elements section that is recolored to a soft pastel blue in the shade #a9c2d6. Within the human silhouette eleven white circles were placed with the measurements of 0.5-0.6 inches that will be used as indicators of pain. These were placed in common pain indicating spots such as the head, shoulders, arms, hands, legs, feet, and abdomen. These markers were symmetrical with each side, with vertical spacing between 1 and 1.5 inches.  On both the right and left side of the body, four facial expressions were stacked on top of each other, creating a total of eight faces in the entire pain management scale. The facial icons were made using the circular shape function of around 1.5 inches in diameter with spacing the intervals of approximately 1 inch in vertical distance with each face, and one inch distance from the right and left margins. The colors of each face were arranged in a gradient order from pink to green. Starting with a pastel pink in shade #f8b0b6, and continuing in vertical order: #fcc0c5, #efc3c7, #ebd9db, #d6dbd7, #aec8b5, #98b8a0, and finally ending with the pastel green shade of #98b8a1. In order from top to bottom column one to two the phrases, all typed with the open dyslexic font: 

• “I feel good”

• “It hurts a little”

• “I feel uncomfortable”

• “Hurts more”

• “This hurts a lot”

• “Really hurts”

• “This is very bad”

• “I need help now” 

The resulting product was then exported out of Canva in PNG Format to allow for better picture quality. The resulting designs were evaluated on the basis of the breakdown analysis questions previously stated. If the design failed to meet the criteria on any of the 4 baseline evaluation criteria it was subject to redesign. 

Results: 

1) Breakdown of the Wong Baker Faces Scale 

The Wong Baker Faces most critically had 4 components that were broken down to be evaluated. 

Component	Description	Evaluation
6 Facial expressions	Faces ranging from smiling to tears based on pain level	Partially Beneficial
Color Usage	Bright saturated colors such as red, yellow, and bright green	Harmful
Verbal cues	Non personalized phrases such as “hurts little bit” and “hurts little more”	Harmful
Nonverbal alternatives	The nonverbal alternative is the number scale for the faces ranging from 0-10	Harmful

Design and Construction of the PEACE Scale: 

Throughout the design process, three preliminary versions of the PEACE Scale were developed before finalizing the finished product. Each version was evaluated with the breakdown scale previously mentioned: supporting clarity of communication, minimizing sensory overload, using literal language, and allowing for alternative communication methods

Design 1: 

Figure 2. First design of the PEACE Scale 

This design was evaluated against the four criteria (refer to Figure 2.): 

• Clarity of communication ✔️

• Sensory minimization ✔️

• Use of literal language ❌

• Alternative Communication Methods ❌

Design 2: 

Figure 3. Second design of PEACE Scale 

Design two was evaluated against the four criteria (refer to Figure 3.) 

• Clarity  of communication ✔️

• Sensory minimization ✔️

• Use of literal language ❌

• Alternative Communication Methods ✔️

Design 3: 

Figure 4. Third Design of PEACE Scale 

Design three was evaluated against the four criteria (refer to Figure 4.) 

• Clarity  of communication ✔️

• Sensory minimization ✔️

• Use of literal language ✔️

• Alternative Communication Methods ✔️

Final Product: 

Figure 1: Final design of the PEACE scale after construction and redesign

This study resulted in the creation of a new pain management scale that is specifically designed for autistic children as seen in Figure 1. The final product includes eight round facial expressions arranged vertically ranging from personalized expressions. The first facial expression starts with a short and personalized sentence with “I feel good” gradually ending with “I need help now”. A body diagram with distinct marking points was included as part of the scale to indicate specific points of pain with the indicated white dots. After multiple revisions the design was finalized to ensure clarity, simplicity, and accessibility for autistic children. This scale was intended to be used in healthcare facilities in replacement of the use of the Wong-Baker faces for potential implementation in both educational and healthcare settings. This scale was made to serve as a tool for neurodivergent children that can be utilized in a variety of settings, and specifically designed for autistic children. The resulting pain management scale with the acronym of PEACE was created to stand for: Pain Expression and Communication Evaluation for Autistic Children. 

Discussion: 

This study aimed to create a new and revised pain management scale to address the specific needs of autistic children in healthcare facilities. The issue that remained a main concern during the duration of this study was that autistic children were provided with the same pain management scale that were provided to neurotypical children, with the most concerning trait being that autistic children are at a higher likelihood of being unable to express their pain, frustration, and distress¹¹. These behavioral challenges can impact the quality of care received from healthcare professionals specifically due to their communication difficulties⁸. Establishing a method of effective communication is essential in every clinical practice, but receptive communication and emotional responses are lacking for autistic children. 

The results featured two main processes which included the breakdown and categorization of the Wong- Baker faces scale as well as the design and creation of the PEACE Scale. The breakdown of the Wong Baker faces scale resulted in three components being deemed as harmful and one component being determined as partially beneficial. The components being deemed harmful (in order) include the Color Usage, Verbal Cues, Nonverbal Alternative. With the one component being evaluated as partially beneficial as the six Facial Expressions. 

Reasoning for component evaluation: 

Six facial expressions: 

While the presence of faces offers a predictable pattern and was originally determined based on a study where Wong and Baker designed the faces based on a methodology focusing on asking children and adults to draw six faces in progressing pain⁹. However, this study had no focus on neurodivergent children and also prompted the children associated with six original spaces to draw the expression⁹. The facial expressions on the WBF are highly exaggerated, with drastic shifts in eyebrows, mouth curvatures, and teardrops indicating high levels of distress. While these changes are regular and easy to choose for neurotypical children, autistic children often find it difficult to interpret the intense emotional expressions due to challenges with facial recognition and emotional decoding. Exaggerated faces such as these (refer to Figure 5) can lead to misinterpretation, emotional distress, and overstimulation¹¹.

Color usage:

The Wong-Baker scale incorporates bright and saturated reds such as red or orange especially at the more severe ends of the spectrum. These colors, although appealing to neurodivergent children, can be triggering for autistic children due to hypersensitivity with visual stimuli according to a study conducted by Nair et al¹⁴. Bright colors have been shown to increase rates of discomfort and only further anxiety levels in autistic children in healthcare facilities¹⁴. 

Verbal cues: 

Since they are not personalized to genuine emotions it can be difficult for autistic children to differentiate between which emotion they feel. Simply increasing the value of hurt does not help anyone differentiate their emotions as each individual has their own interoception scale which differs from person to person¹³. 

Nonverbal alternative: 

The numerical scale from 0-10 does not allow for an alternate method of evaluating pain as there is no defined way of distinguishing the levels of pain on one individual persson, leading to miscommunication and potential mistreatment in healthcare facilities⁵. 

Design and Construction of the PEACE Scale: 

Throughout the design process, three preliminary versions of the PEACE Scale were developed before finalizing the finished product. Each version was evaluated with the breakdown scale previously mentioned: supporting clarity of communication, minimizing sensory overload, using literal language, and allowing for alternative communication methods. The design process was a crucial step in refining the PEACE Scale to better align with the communicative needs of autistic children in healthcare settings. 

The initial design (Figure 2.) adopted a circular layout of faces to evoke an illusion of emotional progression. Minimalistic in design and appearance, this version succeeded in minimizing sensory overload by limiting visual clutter and only emphasizing what was needed. However, it failed to meet two important criteria: usage of literal language, and an alternative communication method. The circular format limited the available space which disregarded any space for text, thereby limiting the opportunities for verbal communication cues. It also relied entirely on the facial cues without providing a secondary means of communication like Nader urges as a necessary measure⁵. This would make Design 1 challenging for nonverbal autistic children. Further, the circular design although aesthetically pleasing was impractical for printing processes in healthcare facilities. 

The redesign featuring Design 2 focused on the two main missing factors in the first design. Design 2 introduced a body diagram as an additional method of communication. This decision was mainly in response to research from Williams et al. who found that autistic children can identify pain more accurately on other body diagrams compared to their own body due to the lack of interoceptive abilities– the ability to perceive and understand pain in an individual's own body¹³. While this addition determined another method of communication, the scale still did not allow space for verbal cues. In addition, the visual disconnect reduced the scale’s visual aesthetic and coherence of both scales. 

Finally, Design 3 (refer to Figure 4.) offered a synthesis of the lessons learnt from the previous design choices. The final layout repositioned the eight faces into two vertical groups: four faces on the left representing lower levels of pain and four faces on the right representing higher levels of pain. This design was able to keep the simplicity, lack of overstimulation, and alternative communication method, while also allowing for text spaces. Color selection in this design also reflected findings from Nair et al. which identified pastel tones calming to children with ASD in comparison to bright harsh colors, allowing for further minimization of sensory overload in healthcare settings¹⁴. This design was finalized as it fit all four criteria of components supporting communication with autistic children. 

The final design and creation of the Pain Expression and Communication Evaluation for Autistic Children directly addresses these issues by creating a tool designed to meet the communicative needs of autistic children. This new pain management scale specifically designed for autistic children fills an outstanding gap in research and clinical practice. Traditional pain scales such as the Wong-Baker Faces scale require verbal descriptions, numeric ratings, triggering colors, and exaggerated facial expressions. However, the PEACE Scale is structured to align with the communicative needs of autistic children. PEACE employs a dual component approach in which it features a body diagram with facial expressions that allows children to express the location and intensity of their pain. 

The use of pastel colors in contrast to the vivid and bright colors used for the current pain assessment scale: Wong-Baker faces with the use of soft pinks, greens, and blues. Pastel shades are less stimulating for autistic children than bright or saturated colors, reducing the risk of sensory overload¹⁴. Many autistic children experience heightened sensory stimulation but with the PEACE scale it allows them to experience contributing to a predictable and low stress environment which progresses and supports clearer communication. 

The facial expressions used in the scale were carefully simplified into eight expressions instead of six (present in the Wong-Baker faces) to avoid the exaggerated and dramatic progression of facial expressions. Exaggerated expressions tend to be difficult for autistic children to interpret and can also cause overstimulation¹¹. By using eight faces instead of six the progression of facial expressions in a slower and less exaggerated manner. By using less intense, more neutral expressions the scale provides a clear distinction that doesn't come off as threatening or demanding, so by progressing the expressions slightly it minimizes any emotional confusion or overstimulation. The words associated with each face are personalized and humanized phrases with an Open Dyslexic font to ensure easier accessibility with reading.

The incorporation of a body diagram the scale offers an alternative, nonverbal method of communicating for children to accurately indicate where they are experiencing pain with distinct marking or pointing points. Previous studies indicate that autistic children are better able to articulate the location of their pain on other body diagrams but are not able to do so on their own . This component is beneficial specifically for nonverbal or minimally verbal children  allowing them to indicate the specific location of their pain without the need of verbal cues. The diagram allows healthcare professionals to be able to rely on their own care independently instead of having to rely on parental perception of pain assessment^11,13.

Beyond identifying and closing a gap in research for a proper pain management scale that is specifically tailored for the needs of autistic children, this study contributes to the growing emphasis for more inclusive tools for neurodivergent children highlighting the need for designs that use use understanding and empathy, which ensures that autistic children and other vulnerable populations allowing them to have access to communication methods that respect their unique needs. 

Limitations:

Although this study is based entirely on previous studies regarding the most preferred and responsive stimuli for autistic children to engage with, the introduction of the PEACE scale the introduction of the PEACE scale is still yet to be tested in direct relation to autistic children. Without this, this study does not have direct numbers to correlate back to the responsiveness of autistic children. 

Another limitation of this study is the lack of variable sources and sources in general that would allow an extensive and thorough compilation of the needs of autistic children. The lack of sources is attributed to this specific gap in research where research and studies are not regularly conducted in relation to the pain management levels and preferences.

The use of eight faces instead of six also presents a limitation to this study. Although the six faces were determined to be partially beneficial due to its aid in reliability and consistency, the rationale behind its partiality on harmfulness (being deemed to be partially beneficial) was due to the limited literature on whether having more choice in regards to the faces would reduce the amount of overstimulation. The problem identified included: the WBF progressed rapidly leading to overstimulation, hence creating eight faces. However, there are no quantitative results that could determine whether the eight faces and slowly progressing faces provide an added benefit to autistic children or whether by solving the issue of overly fast progressing faces, the PEACE scale overstimulates autistic children more. 

Implications:

Using this knowledge, however, this study represents a new approach to pediatric care and pain assessment for autistic children. The unique combination of pastel colors, body diagrams, and a modified Wong Baker faces scale is designed to help autistic and nonverbal children in healthcare facilities to further reduce the high rate of miscommunication and mistreatment that goes into care for autistic children. An implication of this study involves exploring the depth of the sensory friendly design principles in healthcare tools regarding the PEACE scale. This includes testing across various subgroups including children with varying levels of verbal ability, children with different cognitive disabilities, or with the subgroup of autistic children with Hyposensitivity (under responsiveness to a range of sensory stimuli). Although the PEACE scale’s use of pastel colors, and calming visuals aligns with universal research aimed to target sensory overload, it is not specifically designed for autistic children with Hyposensitivity; it is simply made to encourage a more comfortable space to allow autistic children to communicate their needs. Further research should explore the reliability and sensitivity of the scale compared to traditional pain management scales and obtain data on the variability between scores as there is currently no quantitative data to support the user compatibility with autistic children in this study. By conducting further research and comparing the responsiveness to previous pain assessment scales (such as the Wong Baker Faces Scale and the FLACC Scale) and comparing that to the PEACE scale it can be determined whether this creates positive effects for autistic children who already experience a lack of sensitivity. As previously mentioned, studies focusing on a range of nonverbal disorders would be beneficial to establishing the myriad of uses in clinical settings beyond autistic children and justifying its usability with all nonverbal children. 

Conclusion

Despite the growing recognition of disparities in healthcare experiences and outcomes for autistic children, there still remains a significant gap in tools that have been created to aid the specific needs of autistic children¹.Although there exists pain management scales like the Wong Baker Faces Scale, there is no scale that specifically adheres to the needs of autistic children. Through a create process, this study broke down components of the WBF and used previous research to synthesize and create the Pain Expression and Communication Evaluation Scale. Through the PEACE scale it has the potential to make a meaningful and impactful contribution to this gap in research through the creation of an autistic friendly pain management scale that could shape future studies and healthcare practices. 

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