A synthesis of the characteristics of dance interventions engaging adults with neurodevelopmental disabilities: a scoping review

Abstract Purpose Dance can encourage physical activity and promote physical, cognitive, and social development for adults who have neurodevelopmental disabilities (NDD). Dance is defined as a form of expression that may be structured, exploratory, and/or cultural. Current literature supports the benefits of participation in dance for persons with NDD, however less is known about what characteristics support participation in dance. Materials and Methods A scoping review was conducted to synthesize the characteristics of dance interventions, teaching strategies, and outcome measures used to assess the efficacy of dance interventions. Searches were conducted across six databases and the results were screened according to: i) adults ≥18yrs of age with a diagnosed NDD, and ii) the program incorporated activities that fall within our definition of dance. Results A range of dance forms and NDDs were represented across the fourteen studies reviewed. Few provided explicit details of the dance interventions, nor how instruction was adapted. All studies that measured fitness, mobility, balance, posture, and functional activity showed significant improvement. Studies that measured psychosocial and well-being focused on autistic characteristics and showed mixed results. Conclusions Details of interventions, instructions, measures of movement performance, and the relationship between outcomes and the interventions require further development and research. IMPLICATIONS FOR REHABILITATION Dance is a multimodal activity that can improve aerobic capacity, postural control, passive ROM, and strength in adults with neurodevelopmental disability at all levels of function. Participation in dance may be recommended as an option for recreational physical activity as current evidence supports dance as an effective physical activity, and/or supplement to therapeutic goals, with physiological as well as psychosocial benefits. When considering dance as a recreational activity it is important to consider the program and instructors approach, as well as the experience and training of the instructor, in order to best match the goals of the dancer with the goals of the specific program.


Introduction
worldwide approximately 785-975 million persons aged 15 years and older live with a disability; of those, 110-190 million are classified as having a severe, or more complex, disability [1].The term neurodevelopmental disability (NDD) references a group of diagnoses that occur during the developmental period and includes intellectual disability (iD), Down syndrome (DS), cerebral palsy (CP), and autism spectrum disorder (ASD) [2].Similar across NDDs are the: i) category of risk pertaining to parental and social function of the family unit across biomedical, social, behavioural, educational domains occurring during pre-peri-post natal periods [3], ii) differential diagnoses, and iii) physical, cognitive and adaptive behaviours [4,5].The characteristics of NDD are also heterogeneous in nature, varying between individuals and across the lifespan.These can include changes in cognition and adaptive behaviours, such as communication, self-care, functional mobility, and socialization [6].Between 18-21 years of age, persons with NDD typically "age out" of the education system to adult services.Families are often left on their own to find social opportunities and medical care for family members [7].Combined with a lack of adaptive or integrated physical activity (PA) opportunities this transition often increases isolation, anxiety, depression, and sedentary behaviour, resulting in poor health outcomes [8][9][10].Participation in PA is critical for adults with NDD as they are vulnerable to social isolation, respiratory, and cardiovascular disease at an earlier life stage than their neurotypical counterparts [11].Available PA opportunities often welcome individuals who identify with a broad definition of disability rather than limiting participation to a specific population.To better reflect PA opportunities in community we chose to a focus on NDD broadly.
Dance is a multidimensional performing art that engages participants through rhythmic motor coordination tasks, the activation of sensory and perceptual-motor systems broadly, imagination, and social interaction, in relation to musical accompaniment [12,13].Consistent participation in dance may encourage further participation in PA for enjoyment and health benefits as it promotes physical, cognitive, and social development, and supports the management of mental health [13,14].Despite the growing evidence for the benefits of dance for persons with disabilities, the availability of programs designed for persons with NDD remains limited [15].
Dance is also an expression of self, emotion, and heritage across most cultural and socioeconomic contexts [12].The term "dance" can encompass a range of genres such as formal, highly structured (e.g., classical ballet, jazz), exploratory (e.g., creative dance), street dance and cultural dance, as well as dance-based fitness.each of these genres requires learning complex whole body movement sequences including technical and whole-body sensorimotor skills through the reproduction of observed movements and instruction with musical accompaniment [16][17][18].Formal, exploratory, street, and cultural genres of dance routinely require the communication of emotion and/or a narrative, the fine-tuning of movement, the goal of attaining nuanced aesthetic, and the intentional use of the musical pulse, rhythm, and phrasing [13,17,19,20]. in contrast, the goal of dance-based fitness is to challenge aerobic and physical fitness through continuous movement and does not typically engage the previously described characteristics.Therefore, dance-based fitness interventions were excluded from this review [12,21,22].
Systematic reviews and meta-analyses examining the effects of dance and physical activity interventions for adults with disabilities span genres of dance and encompass both developmental (CP, [9]; ASD, [23] iD, [24]), and acquired diagnoses such as Parkinson's disease [25,26,27] and fibromyalgia [28].Overall, this evidence indicates that dance and movement to music may improve physical function (i.e., body awareness, postural stability, balance), mobility (i.e., gait, walking, strength of lower limbs), health, and health related quality of life.Although the evidence supports the benefits of participation in dance for persons with NDD broadly, less is known about what specific program characteristics and instructional strategies are most beneficial, nor how efficacy of the dance programs/interventions have been measured.we chose to focus this scoping review on adults with NDDs because there is a need to understand program characteristics and instructional strategies that are specific for adults with NDDs [15].
The guiding framework for this scoping review was the ecological model of motor development.This model proposes that both motor and perceptual development are driven by the interaction of the individual, the task, and the environment [29][30][31].in this review the environment is defined as the characteristics of the dance class and instruction, if/how adaptations are provided in relationship to the individuals' physical and affective characteristics, and, in a research setting, which outcome measures were used.The ecological model posits that instruction should consider the capabilities of the participants and is a key factor in both motivation and motor development [29,30].instruction can include a variety of forms of augmented feedback, including strategies, cues, directions, or the posing of questions to encourage creativity and group interaction.The outcome measures used across the literature are considered in the present review as the variety of measures used suggest how the efficacy of dance interventions have been evaluated and which of the ecological domains (the individual, task, or environment) have, or have not, been considered and evaluated.
in alignment with Arksey & O'Malley's [32] reasoning for engaging a scoping review methodology, the primary objective of this review was to determine and summarize the characteristics of, and common instructional strategies used in, dance interventions for adults with NDDs.The secondary purpose was to synthesize the outcome measures used to assess the efficacy of dance as an intervention.The tertiary purpose was to consider the relationship between the reported outcomes and the characteristics of the dance interventions.The findings from this scoping review will deepen our understanding of how dance has been used as an intervention, what instructional strategies have been engaged, and what outcome measures have been used specifically with adult dancers with NDDs.

Method
A scoping review was conducted using the five-stage framework [32] informed by Levac [33] and Colquhoun [34].Specifically, we conducted the scoping review using the five stages proposed by Levac (i.e., the identification of the research question, relevant studies, the study selection, charting the data, and collating, summarizing, and reporting of the results).The review process was iterative, with continued refinement of terms and definitions, as well as explicit documentation of the review process [34].The review is also reported according to the PRiSMA-ScR reporting guidelines ( [35]; See supplemental materials).The following research questions were considered: i) what are the characteristics of, and instructional strategies used in, dance interventions for adults with NDDs (e.g., type, structure and form of the class, teaching strategies, use of music, duration)?ii) in what ways has the efficacy of dance interventions for adults with NDD been measured?And iii) How do the instructional strategies and outcome measures used relate to the reported outcomes of the dance interventions for adults with NDDs?

Identification of relevant studies
A librarian from the University of Manitoba was consulted to establish broad search terms [32].To retain a broad scope of the search no limits were set for study design.Relevant studies were sought using three approaches: i) using the search terms related to the aim of the study (danc* AND disabilit*, dance* AND autis* and the combined queries of both combinations were used in each database search), ii) hand searching of reference lists of relevant reviews to identify any further studies related to the objectives of this review, and iii) a citation chasing search was conducted by hand searching the citation lists of three relevant articles of interest.Three populations were identified in the original search and therefore one article of interest was selected from each population that was: published within five years of the original search, fit the definition of dance for this study, and focused on either ASD, iD, or CP [36][37][38].Searches were conducted in Scopus, Pub Med, eRiC, APA Psych info, Academic Search Complete, and Cochrane databases.Additional searches were also conducted using the search terms danc* and autism, ASD, intellectual disability, cerebral palsy, Down syndrome, DS, and developmental disability (separately).A sample search strategy is provided in the supplementary materials.An additional eight articles were identified using a citation chasing strategy.The original search was conducted in March of 2020 and updated in July of 2022.

Study selection
The search results were uploaded into endNote TM 20 reference manager software [39] and duplicates were removed.Two primary reviewers (JL and eB) conducted an independent screening process, and a third reviewer was available in case of any disagreements (CG).Articles were screened for eligibility using Rayyan (a web-based systematic review platform that facilitates blinded review of articles; [40]).each study must have evaluated dance as an intervention, rather than as a dialogue on the experience of dance performance, or a discussion of a dance company or performance experience.Specific eligibility criteria for articles to be included were: i) studies engaged adults (≥18yrs of age, or if the mean age of all study participants was ≥18yrs) diagnosed with NDD; ii) dance interventions or programs that fit the definition of dance; iii) original articles were written in english and published in peer-reviewed journals; and iv) articles were available through database subscription or interlibrary loan.

Charting the data
All data were extracted by the two primary reviewers and input into a spreadsheet in Microsoft excel® (version 6.15).extracted data included: (i) title, (ii) author name/s and year published, (iii) population, (iv) age and number of participants and participant characteristics, (v) purpose of the study, (vi) the form of dance used in the intervention, (vii) description and duration of the dance intervention, (viii) training or qualifications of instructor and location of intervention, (ix) measures used, (x) study results and significance.each study was then categorized for sorting purposes according to the dance form and the details of the intervention provided.

Collating, summarizing and reporting the results
The data was synthesized using two approaches: i) a numerical summary and description of the types of interventions and instructional approaches, and ii) items were organized and summarized qualitatively to consider the outcomes and implications of each study [34].

Results
From the initial search (n = 2,287) a total of seventy full text articles were screened and a total of 14 studies met the inclusion criteria (see Figure 1).

Physical fitness, balance, and mobility measures
Seven of the fourteen studies (50%) included physiological and balance measures or assessments of functional activities [37,[45][46][47]49,50,53]. All seven studies report improvements in physical fitness, balance, mobility, and functional activity with participation in dance.while a range of NDD were considered in this category of physical measures, none of the studies that included measures of physical performance included dancers on the autism spectrum (see Table 1).Notably, three studies did specifically engage adults with more complex CP diagnoses (GMFCS level iii-v [37,45,46]).Overall, the seven studies in this category demonstrated that for a range of NDD, participation in dance can influence significant changes in upper and lower body strength and flexibility (NDD; [53]), aerobic capacity and lower leg joint ROM (CP; [45,46]), both dynamic (DS and iD [47]) and static (DS; [50]) balance, and independent function, self-care, mobility, and communications (CP; [37]).

Psychosocial and behavioural measures
Seven of the fourteen studies included measurement of psychological, social, or behavioural aspects with inconsistent results.

The relationship between intervention delivery and outcomes
To better understand why dance may or may not be an effective and meaningful form of PA in relation to each category of outcome measure, any improvements (or lack thereof ) in the reported outcome measures were reviewed in relation to each specific dance intervention.Five of the fourteen studies reviewed (36%) did not provide a transparent or comprehensive description of the dance intervention and/or clear links between the results and intervention (see Table 4 in supplemental materials).The remaining nine studies are presented in more detail below.

Physical fitness and mobility outcomes
Of these nine studies, five used unique dance methods and engaged physical fitness or mobility measures or assessed functional activity.The level of detail provided ranged from low to medium (as defined in Table 4 in supplementary materials).Two separate groups of authors linked the significant improvements in dynamic balance and postural control of individuals who have iD [47] and DS [50] in Greek folk-dance and mixed dance (classical, modern, and creative dance) interventions to the integration of sensory stimuli through the vestibular, auditory, and visual systems during the interventions. in one case, a contemporary dance intervention that engaged locomotion and body mobility was linked to improved physical fitness, balance, posture, and coordination [37].improved cognition was also linked to the processes of learning and memory, and the refining of sequential movements in relation to the rhythmic musical accompaniment [37].The authors of another study, using the same intervention, linked the intentional movements used in the intervention to the cognitive engagement in dance, as well as the use of the upper and lower limbs, resulting in enhanced kinesthetic awareness, musicality, and the physical expression of emotion [45].These enhanced concepts are suggested to be a result of engaging the processes of movement control, providing distraction from physical pain and/or daily stressors, a change in emotional state, and the practice of building awareness of self through movement [45].Passive range of motion of the hip, knee, and ankle joints (using a pendular fleximeter) CP (GMFCs ii-V) World health organization Disability assessment schedule (WhoDas), Gross Motor Function Classification system (GMFCs), Functional independence Measure (FiM) nDD strength (using dynamometer), Knee extension test, timed-up-and-Go (tUG), 30s sit-to -stand test, Functional Reach test (FRt) none of the studies used DMt as an intervention.

Psychosocial outcomes
Four of the nine studies used psychosocial measures to assess change; in all cases these studies used a DMT approach.The level of detail provided in these four studies ranged from Medium-High to High (see Table 4 in supplemental materials).The use of DMT-music therapy intervention that engaged rhythmic activities such as music, singing and rhythm, as well as a range of body movements and imagery is suggested to have led to improved impulse regulation, improved attention and emotional self-control in individuals with ASD [41].A mirroring strategy often used in DMT was suggested to have elicited improvements in the self-reported outcomes of decreased negative affect and expression of emotion [42], body awareness, self-other awareness, psychological well-being, and social skills, as well as therapist observed self-other distinction and enjoyment in adults with ASD [43].The effect of (DMT) mirroring strategies that pair individuals with ASD together did not have a significant effect and was linked to persons with ASD often having difficulty expressing themselves in social situations [44].

Discussion
This scoping review focused on the literature pertaining to dance interventions that engaged adults who have NDD.The specific aims of this review were to: i) identify the characteristics of, and strategies used in, the dance interventions, ii) summarize which measures have been used, and iii) consider the explicit relationship between the reported outcomes and the characteristics of the dance interventions as discussed in each study.The ecological model of motor development was a guiding framework as it considers both motor and perceptual development to be shaped and driven by the interaction of the individual, the task, and the environment [29][30][31].
How the learning environment is designed, including how instruction is provided or structured, is directly relevant to performance improvements, motivation, and learning [29,30].

Characteristics
Overall, the lack of detail and transparency of the intervention descriptions was identified as a concern for replication in research or applications in communities.Four of the fourteen studies shared the same approach (DMT) and provided enough detail to facilitate replicability of the study [41,43,44]. in contrast, those studies that engaged other adapted dance approaches, such as Greek, ballroom, classical, modern, and creative movement dance forms, were described inconsistently.in addition, of the studies that engaged dance assistants (n = 5), only three of these indicated that training was provided for the assistants.even if training was indicated, details on the form and frequency of training, and the level of involvement of the assistants in how instructions and/or movements were adapted to suit the capabilities of the dancers, were not reported.it is of interest and encouraging that three studies did include individuals with more complex CP (GMFCS iv and v; [37,45,46]).However, details of how instructions and/or movements were adapted to suit the capabilities of the dancers were not reported.Overall, information regarding the adaptation of movement, and how dance assistants were instructed to engage with the dancers, are needed to address how, and if, the environment was adapted.More specific details about the instructional techniques are important to include for both the replication and application of the studies.

Conflicting definitions
DMT is described as a primarily psychological intervention that uses dance as a psychotherapeutic tool to achieve clinical goals rather than dance as solely a recreational activity [44,53].Thus, DMT takes a biomedical approach to adapted dance, and therefore conflicts with the definition of dance used for this scoping review (i.e., where participation in dance is supplemental to therapies).For this reason, the remainder of the discussion will not include the DMT studies (n = 5), thus reducing the number of studies reviewed to nine.This shift further highlights the need for research on dance as a recreational intervention to i) provide greater descriptions of dance interventions directed to adults with NDD, ii) develop guidelines and/or training that are applicable to a range of dance forms, and iii) engage the broader dance community through knowledge translation.

Measures
Three areas of concern arose regarding the types of measures used: i) in many cases the measures were not validated for NDD, ii) the psychosocial measures often required comparison to a normative scale, or were self-report measures, and iii) assessments of movement quality were not included.The physical fitness and mobility measures (see Table 1) did provide objective assessment of how participation in dance could benefit overall physical function and, apart from ASD, appear to relate to common issues reported with each diagnosis.Although the physical fitness and mobility measures were not validated for NDD, they did assess pre to post change, rather than comparison to normative scales.The psychosocial measures used (see Table 2), although not always validated for NDD, do provide insight into perceptual and motor ability, emotion, and well-being.The latter measures were predominantly used in dance intervention studies that focused on ASD.These measures were administered as either a scale where a rank or score described a level or category of behaviour, or as a self-report measure where the participant completed a questionnaire.
Although the language used in self-report tools, such as the Personal wellbeing index for intellectual Disability, have been modified for the iD population [54], the nature of the self-report tool inherently assumes a level of participant understanding and comprehension.Absent from the literature are measures of movement performance.Using movement performance and kinematic measures to assess changes in temporal and spatial characteristics would allow researchers to track any improvement in movement control without labelling change as "good" performance, or in relation to normative definitions.To demonstrate how movement performance might be improved through dance it is recommended that measures such as the reciprocal Fitts' task, reaching or choice reaction time tasks, and movement kinematics be considered [55,56].Because of the heterogeneity of the physical characteristics in NDD and the influence of environmental factors on learning, it is also recommended that movement effectiveness be assessed through measures that are validated for NDDs and/or that consider the relationship between the individual and their environment [57].For example, to address the diversity of individual characteristics (e.g., autonomy, quality of life) and inter-related concepts (e.g., anxiety, communication) within neurodiverse populations the international Classification of Functional, Disability and Health (iCF) Core Sets have been developed for Autism, ADHD, and Cerebral Palsy [57,58].

The Intervention-Outcome relationship
To understand this relationship the details of the dance interventions (non-DMT) were reviewed.Four studies provided clear links between the study outcomes and intervention characteristics but provided minimal intervention details (see Table 4 in supplemental materials).For example, reflecting on the group nature of Greek folk dances, the bilateral support provided when holding hands in circle dances is proposed to enhance dynamic balance, cooperative group work, and proprioceptive input [47].This characteristic is suggested to have played a role in strengthening the integration of vestibular, auditory, and visual information [47].However, details about how, when, and how often the circle and partner work was used throughout the intervention was not reported.Likewise, Gutiérrez-vilahú et al. [50] linked improvements in static-stance stability to how a mixed dance intervention was explicitly designed to focus on core strength, proprioception, and balance (with and without vision).The explicit use of visual cues was found to be an effective strategy for the development of balance control.The authors do provide an outline of the intervention and the intention of each section without reporting explicit detail.

Limitations
while we worked to conduct a comprehensive scoping review, there are limitations that must be acknowledged.First, our specific definition of dance may differ from others' definition, thus the literature captured may be considered by some to be less inclusive than other literature [59].we chose to focus on dance as recreation as opposed to therapy because the focus of this review was on adults with NDDs, who have expressed a desire to have meaningful activities that are not medicalized [60].That said, we acknowledge that it is possible to use a hybrid approach where dance could be both recreational and therapeutic.Second, while the focus of this review was to capture the scope of available research, the searches were limited to peer-reviewed journal articles published in the english language.Third, the heterogenous nature of the included populations (ASD, iD, DS, CP) may limit the specificity to certain physical, sensory, and cognitive differences unique to each population.At the same time, it is critical to recognize the additional heterogeneity within a given diagnosis, as well as the commonalities across NDDs.

Recommendations and conclusion
Details of the dance interventions and adaptations of dance, measures of movement quality, and the linking of outcomes in relationship to the characteristics of the dance interventions were areas found to be lacking in the reviewed studies. in addition, studies engaging persons with autism were focused on psychosocial constructs such as behaviour and empathy rather than on physical fitness or mobility.The addition of detailed intervention descriptions that include examples of instruction, strategies, and cues, will improve the clarity of the interventions, and enhance both the reproducibility and transferability of the findings to applied settings.Given the heterogeneity of NDD, and the range of functional and communication abilities inherent across NDD, it is recommended that future studies engage a person-centred approach, examine ways to adapt the dance environment, and explicitly address how and in what ways dance instruction has been adapted [29,61].it is also recommended that future studies examine which specific aspects of dance and dance instruction (e.g., mirroring, holding hands, interacting with music) might influence changes in physical fitness, mobility, quality of movement, or psychosocial constructs.The addition of measures of movement quality will provide a deeper understanding of how dance may produce meaningful change in movement performance.Further, examining the relationship between specific characteristics of the dance interventions and study outcomes will provide a better understanding of what characteristics are key for observed changes.A more direct link between intervention details and observed improvements will also provide meaningful information for the application of specific approaches to inclusive adaption of dance instruction.The application of these recommendations across NDD populations will inform theory and practice of inclusive and adaptive pedagogy, specifically, the culture and praxis of teaching inclusive dance in adaptive settings.

Figure 1 .
Figure 1.Flow chart of the search process and results.

Table 1 .
Physical fitness, balance, and mobility measures.

Table 2 .
Psychosocial and behavioural measures.