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(Article 1)​ Exploring What Works in Art Therapy With Children With Autism: Tacit Knowledge of Art Therapists. Children​ with autism spectrum disorders (ASD) are often referred to ​arttherapy​. To investigate what works in ​art​ ​therapy​ with ​children​ with ASD, the tacit knowledge of 8 experienced ​art​ therapists was explored through interviews. Promising components were arranged into the Context and Outcomes of ​Art​ ​Therapy​ (COAT) model. According to the respondents, ​arttherapy​ with ​children​ with ASD contributes to becoming more flexible and expressive, more relaxed, and more able to talk about their problems in the therapeutic setting as well as in their home situation. Considering the evidence in this study, further empirical research into the process and outcomes of ​art therapy​ with ​children​ with ASD is strongly recommended. Children​ diagnosed with autism spectrum disorders (ASD) have qualitative limitations in social communicative skills and often exhibit stereotypic and repetitive patterns in behavior, interests, and activities (American Psychiatric Association, [ ​1​]; De Bildt et al., 2007; Doreleijers, Boer, Huisman, Vermeiren, & De Haan, [11]; Rozga, Andersson, & Robons, [38]). These ​children​ have atypical ways of information processing. Three concepts of information processing are often described as characteristic of the problems of ​children​ diagnosed with ASD (Swaab, [48]). The first concept, theory of mind, refers to difficulties in understanding feelings, thoughts, ideas, and intentions of themselves and others (Baron-Cohen, [ ​3​]; Lucangeli, [23]). The second concept relates to deficits in executive functioning, which implies that ​children​ with ASD have problems with planning and cognitive flexibility (Ozonoff, Pennington, & Rogers, [30]; Rozga et al., [38]). The last concept refers to a weak central coherence: the inability to interpret details as part of a broader context or system. Atypical sensory processing is a core feature and appears as ​children's​ high or low sensitivity to environmental stimuli (Happé & Frith, [17]; Kenet, [20]; Mottron, Dawson, Soulières, Hubert, & Burack, [28]; Rozga et al., [38]). In a Delphi study on ​art​ ​therapy​ research, experts placed the importance of research with individuals with ASD as third in importance (Elkins & Deaver, 2010; Kaiser & Deaver, [19]). In a recent review, Schweizer, Knorth, and Spreen ([43]) found no experimental study testing outcomes or effects of ​art​therapeutic interventions for children​ with autism, although one was published later. Schweizer et al. (2014) found

only a small number of well-documented case descriptions. This lack of evidence can probably be explained by the traditional emphasis on tacit knowledge that ​art​ therapists claim to have at their disposal (Korthagen, Kessels, Koster, Lagerwerf, & Wubbels, [21]; Polanyi, [33]; Smeijsters & Cleven, [46]). Indeed, nonverbal or ​art​-based expressions and attunement to clients refer to processes that largely depend on personal orientations of therapists, which are presumed difficult to measure quantitatively. Also, subjectivity in therapeutic measurements might be an issue that has contributed to the lack of investigation and measurement of ​art​ ​therapy​ processes (Veerman & Van Yperen, [52]). Despite these factors it remains important to know whether ​art​ ​therapy contributes to successful treatment of ​children​ with ASD. The purpose of our study was to find and define promising practice-based elements or components that could contribute to practice-based evidence of ​art​ ​therapy​ with children​ with autism. Information was obtained from experienced ​art​ therapists who worked with these ​children​. Research on treatment for ​children​ with autism is scant (Boendermaker et al., [ ​5​]; Schothorst et al., 2009; Schweizer et al. [43]; Slayton, D'Archer, & Kaplan, [45]). One experimental study (​N​ = 19) was found about ​art therapy​ used for stimulating recognition of emotions in facial expressions (Richard, More, & Joy, [36]). Children​ with autism are regularly referred to ​art​ ​therapy​ (Martin, [25]; Teeuw, [50]) with the aim to aid in coping with their communication problems, behavioral problems, and low self-esteem (Schweizer, 2014; Schweizer et al., [43]). Martin ([25]) indicated that ​art​ is an expressive means used by different professionals working with ​children with ASD. She stated that there are many interesting publications on successful treatment stories but systematic research is lacking. This research is needed to specify and underpin the contribution of ​art​ ​therapy​ with ​children​ with ASD. Children​ with ASD are expected to benefit from a nonverbal treatment such as ​art therapy​ because experiences that involve touching, looking at, and shaping ​art materials enable expression (Malchiodi, [24]; Rubin, [39]; Schweizer et al., 2009). This could stimulate development and reduce some problem behaviors. Gilroy ([15]) argued that ​art​ ​therapy​ can move ​children​ with autism beyond stereotypical behaviors and encourage sensory, perceptual, and cognitive development. In a small-scale, quasi-experimental study, some evidence was found that the ​arts therapies​ (music ​therapy​, drama ​therapy​, and ​art​ ​therapy​, as well as psychomotor therapy​) might contribute to positive changes in social behavior, attention span, and relaxation (Pioch, [32]). A pre- and posttest design was conducted with 28 ​children​ in an experimental condition and 6 in a wait-list control group; all were diagnosed with ASD in a school for special education. Teachers and ​arts​ therapists completed a range of standardized tests. Because the experimental condition in this study contained a mix

of drama ​therapy​, music ​therapy​, ​art​ ​therapy​, and psychomotor ​therapy​, it is difficult to unravel the effects of the different ​therapies​. In another small study, Teeuw ([50]) surveyed treatment aims and outcomes among members of the Dutch Organization of ​Art​ Therapists (Nederlandse Vereniging Beeldend Therapeuten [NVBT]). Twenty-eight ​art​ therapists working with ​children​ with ASD responded to Teeuw's survey and results revealed that the main reasons ​children with ASD were referred to ​art​ ​therapy​ were social problems, lack of awareness of their own (problematic) behavior, difficulties with expressing themselves, stress, problems with focusing attention, low frustration tolerance, rigid behavior, and problems with planning and reality testing. Often these ​children​ were unhappy and had low self-esteem. The ​art​ ​therapy​ treatment goals identified were the development of possibilities as well as an increasing ability to deal with disappointments, the development of self-image and self-esteem, learning to look at and listen to others, learning to ask for help and to develop a cooperative attitude, learning to set limitations, developing problem-solving capacities, expressing emotions, becoming better at distinguishing reality from fantasy, having a greater attention span, having fewer fears, and showing better frustration tolerance and more flexible behavior. Children​ with autism experience problems that are often related to information processing, which has far-reaching consequences for their understanding of themselves and the world around them. There are some indications that ​art​ ​therapy​ might provide a pathway for these ​children​ to cope with some of their problems. Because of a lack of empirical knowledge on ​art​ ​therapy​ with ​children​ diagnosed with ASD, one of the initial steps that might be taken to gain more insight into what this treatment actually implies is to take a closer look at the experiences of ​art​ ​therapy practitioners to discover their experiences closely. ​Art​therapists partly work by intuition (Smeijsters & Cleven, [46]). Reproduction of and reflection on their actions in ​therapy generates valuable information that could be described as articulating tacit knowledge (Polanyi, [33]). Our study is a first step in exploring promising components of ​art therapeutic treatment with ​children​ with ASD to develop an evidence-based protocol in the next stage of building evidence. Therefore, we explore the tacit knowledge of ​art therapists concerning what they consider relevant elements or components in ​art therapy​ with ​children​ with ASD. More specifically, the following topics were addressed: the opportunities these ​children​ might encounter to express themselves in ​arttherapy​, the appearance of these ​children's​ problems while using ​art​ materials, the repertoire of actions the ​art​ therapist uses in treatment, the context and conditions of treatment that could stimulate behavioral change for these ​children​, and the typical personal and behavioral characteristics of these ​children​ that are sensitive to change by ​art therapeutic interventions.

Method This study was conducted in accordance with a qualitative, practice-based research methodology based on grounded theory (Charmaz, [ ​8​]; Linesch, Aceves, Quezada, Trochez, & Zuniga, [22]; Metzl, [27]; Pénzes, Van Hooren, Dokter, Smeijsters, & Hutschemaekers [31]; Strauss & Corbin, [47]). With a bottom-up approach, a theoretical frame about working elements in ​art​ ​therapy​ with ​children​diagnosed with ASD was elaborated based on the data.

Participants Eight ​art​ therapists were selected from the professional network of the first author using convenience sampling (Babbie, [ ​2​]). The main criterion for inclusion was having at least 2 years of experience as an ​art​ therapist with the target group, ​children​ diagnosed with ASD who were 8 to 12 years old with normal or high intelligence. The ​children​ varied in terms of specific behaviors, interests, and intellectual potential. To ensure a diversity of settings, ​art​ therapists from three different work venues were selected: Two were schools for students receiving special education, three were private practices, and three were day treatment clinical settings in the four northern regions of the Netherlands. All therapists were (associated) registered members of the national professional ​art therapy​ organization, had at least 2 years of supervised experience, and were female (there are few male ​art​ therapists in the country).

Procedure This study was exempt from institutional review because it used anonymous examples from anonymous participants. Data were collected from November to December 2011. Therapists participated in a 90-min, semistructured, in-depth interview (Charmaz, [ ​8​]) during which they were asked for their opinions and experiences with working with children​ with ASD. Each interview started with a general question: What are typical characteristics of the ​art​ of ​children​ with ASD in ​art​ ​therapy​? Subsequently, the following topics were explored: reasons why these ​children​ were referred to ​art therapy​, including their context; conditions of treatment, including duration and phasing; methods used; therapists' behavior and activities; and treatment results. Special attention was given to typical examples of sensory experiences with ​art​ materials, planning skills, and collaboration skills. Each respondent was specifically asked what makes ​art​ ​therapy​ appropriate or inappropriate for ​children​ with ASD. Finally, respondents were invited to support and clarify their stories by showing ​art​ therapeutic products of the ​children​ concerned. All interviews were audio-recorded.

Data Analysis

Interviews were transcribed verbatim and analyzed with an inductive strategy in different stages (Charmaz, [ ​8​]; Strauss & Corbin, [47]). First, significant statements and meanings of the respondents were identified, defined, and interpreted by repeatedly reading the transcripts. Second, codes and categories emerged by comparing texts, research topics, and the codes and categories (Bryant & Charmaz, [ ​6​]). During this first stage of open coding, each of the eight interviews resulted in 50 to 80 codes. Third, in a process of constant comparison (Charmaz, [ ​8​]), codes were compared and adapted, guided by an analysis of content, and (re)labeled anew with names such as success experiences, themes, symbols, fantasies in artwork, and structuring or supportive interventions. As a final fourth step, coded text fragments were related to each other and organized in a hierarchy of main and subcategories (i.e., axial coding). During data gathering and analysis, considerations for coding and categorizing were secured in memos stored digitally as well as on paper. To ensure reliability of data processing and interpretation, the transcripts and coded texts were controlled by the respondents (i.e., member checks were done) and by various rounds of peer reviews (i.e., other researchers critically read the coded texts). Continuous sorting of data led to a hierarchy of categories that we shaped in a circular scheme or model, which will be explained in the results section. The model clarifies the relations between categories, and appears as a possible theory (Charmaz, [ ​8​]).

Results The data were grouped according to a scheme with four main categories. The first category that emerged in the data analysis was ​art​ materials and expressions of the child​ with autism. The second category that emerged was therapeutic behavior: what strategies the ​art​ therapist used to invite the ​child​ to express visually. The third category was the influence of the context of the ​art​ therapeutic treatment of ASD children​: referral, contact with parents, ​art​ ​therapy​ space, and ​art​ materials. Finally, the outer ring refers to the outcomes of ​therapy​, which, according to the respondents, are dependent on the other three main categories in the model. Categories and subcategories in this scheme are based on a varied set of practice examples from the art​ therapists we interviewed. We titled this the context and outcomes in ​art​ ​therapy (COAT) model with ​children​ with ASD seen in Figure 1. The four main categories are used as a frame for presenting our results, and are presented in Tables 1, 2, 3, and 4. We applied a preliminary version of the model in a systematic review of clinical case descriptions (Schweizer et al., [43]). Graph: Figure 1. Context and Outcomes in ​Art​ ​Therapy​ (COAT) Model Note. AT materials & expressions = ​art​ therapeutic means and modes of expression for the ​child​.

Table 1. Category: ​Art​ Therapeutic Materials and Expressions

Key Phrases Statement and Number of Interviewees

Enjoyment; taking care of product

Child enjoys creating and taking care of the art (n = 8).

Sensory elements stimulate change

Sensory elements, especially visual and tactile, stimulate change in rigidity (n = 8).

Product offers opportunities to talk

The product remains after creation, giving concrete opportunities to talk about positive experiences and difficulties (n = 8).

Improvement of communicati on

Communication between art therapist and child improves during art making (n = 8).

Subcategory : Learning From Experiences With Art Materials

Subcategory: Art Making Aids Behavior Change

Key Phrases Statement and Number of Interviewees

Key Phrases

Statement and Number of Interviewees

Sensory experiences through art

Extreme responses to materials (total absorption or resistance) is a restricted behavior pattern that improves (n = 8).

Developme nt of flexibility

Making art and talking about the process helps child experience alternative behavior (n = 8).

Variation in shapes is stimulated

Making more variable shapes is stimulated (n = 8).

Developme nt of coping

During art making the child is helped learning to deal with disappointment by trying other solutions (n = 7).

Variation in stereotyped images

Making variations in stereotypical images is stimulated (n = 8).

Developme nt of self-esteem

Success with art contributes to self-esteem and to engaging in more complex activities (n = 6).

Better focus of attention

Looking at art, touching materials, and creating art helps focus attention (n = 5).

Developme nt of planning and choice making

Completing art using task sequencing helps develop planning skills (n = 5). By providing choices from a selection of colors or materials choice making improves (n = 4).

Table 2. Category: Behavior of ​Art​ Therapist

Keywords Statement and Number of Interviewees Active attunemen t

Directive and supportive attitude toward perceptions and nonverbal language of the child; verbal and nonverbal attunement during session creates a safe and stimulating environment (n = 8).

Structurin g activities and time

Time and activities are structured so the child focuses on art making. Materials and themes offered should connect to the inner world of the child with the aim to stimulate varied experiences and expressions. Most art therapists make a plan with the child about something the child wishes to make. This supports understanding whether the child can create what is in his or her mind (n = 8).

Sharing experienc es

This varies from looking together at the art and at each other to stimulating the child to ask for support when needed (n = 8).

Connectin g words to experienc es

Supporting the child to give words to experiences and offering psychoeducation about ASD stimulates self-acceptance (n = 6).

Table 3. Category: Context of ​Art​ ​Therapy

Keyword s

Statement and Number of Interviewees

Referral procedu re

A clear referral procedure with explicit entry criteria was not mentioned. Child brings a letter from the teacher to the art therapist; a school or a

social worker refers to a private practice; a social worker refers to art therapy (n = 8).

Reason s for referral

Problem behaviors at home, self-image, difficulties understanding social situations, difficulty focusing, insecurity (n = 8).

Treatme nt aims

Expressing feelings, improving flexibility, improving self-esteem, improving planning skills, and empowerment (n = 8).

Table 4. Category: Outcomes of ​Art​ ​Therapy

Keywords Statement and Number of Interviewees

Improved expression

Children become more expressive, make art that is more personal, verbalize more about problems such as being bullied, experiencing divorce, or loss of family member (n = 8).

Improved self-image

Children learn how to deal with anger and frustration, how to direct attention, as their enjoyment of art activities grows. They are more able to consider their behaviors and how to function better; their self-esteem and self-confidence improve (n = 8).

Improved flexibility

As part of more flexible behavior, children are more relaxed, can make choices more easily, and are better at planning (n = 8).

Transfer of improveme nt

Improved skills and behavior reported by parents and teachers (n = 8).

Art Therapeutic Materials and Expressions Respondents were asked about the ​children's​ behavior in ​art​ ​therapy​ sessions with respect to their preferences for specific materials, techniques, symbols, or ​art​ forms, and what these expressions looked like. Table 1 shows crucial elements according to respondents. Table 1 is divided into two sections: the ​art​-related expressions and the problem-related expressions. One of the responding therapists gave an example of making ​art​ as an opportunity to express emotions when frustrated: Most ASD ​children​ have in their mind already what they want to create. When not easily realized, the ​child​ has difficulties accepting the situation: materials and tools are bad, I don't have exactly that specific kind of saw as father has at home: "You never have the tools I need ..."

Therapeutic Behavior of the Art Therapist The second category that emerged was therapeutic behavior: strategies the ​art therapist used to invite the ​child​ to express visually. In this category the focus is explicitly on the working attitude of the therapists. Table 2 shows four aspects of the

working attitude. An ​art​ therapist offers verbal support in a structured way and talks with the ​child​ about his or her experiences working with ​art​ materials. As one of the respondents said: Giving words to difficult experiences is a quality of ​art​ ​therapy​, because while creating something there is always a problem or an impediment. Often something unexpected happens with the material. And because this is not happening in a social relationship, it is not such a burden to talk about it. Giving words to experiences is enabled by the material experiences. Another explained: At a certain moment I told him, "You blame the crayon, you blame the paper, and it fits with having [this diagnosis], to blame everything around you. You are right, the material is not easy to use. But now you are 12 years old, and close to puberty and high school. So now you should start looking at your own part and what your influence could be for a positive change in this situation.

Context Table 3 provides information about the third circle in Figure 1, reasons for the ​child's referral and source of referral. We asked these questions: Are there specific indications for ​art​ ​therapy​ to help ​children​diagnosed with ASD with their problems? Are there specific behaviors of the ​child​ diagnosed with ASD to decide that ​art​ ​therapy​ might offer opportunities for behavioral change? No respondents mentioned specific indications for ​art​ ​therapy​ treatment and referrals were received from teachers or social workers. As one explained, "We mainly work with referrals about the behavior of the child​, such as the ​child​ has problems with reciprocity, attunement, emotion-regulation." Reasons for referral included problem behaviors at home, self-image and self-esteem difficulties, difficulty focusing, difficulty understanding social situations, feelings of insecurity, need to improve planning skills, and need to improve self-expression.

Outcomes Respondents were invited to talk about what they conceived of as typical ​art​ ​therapy outcomes and in what way these outcomes were reflected by the ​art​ and the ​child's behavior during ​art​ making, and behavioral changes in the classroom and at home. In Table 4 changes in behavior, which are visible during ​art​ making, are detailed. Changes included improved expression in ​art​ and in talking, improved self-image, and improved flexibility. This example illustrates the transfer of outcomes at home related to reduction of problem behaviors. An ​art​ therapist said: I remember a mother who told me that her son became more flexible: His football shoes don't have to be placed just in the cupboard anymore; they also may be placed in the

hall ... And when we have other peanut butter, my son is not disturbed anymore. And others may even share his peanut butter. Another therapist talked about a ​child​ becoming more expressive: "What parents tell me often is: 'He talks more.' And what they mean is that he talks more about how he feels: Previously the ​child​ was closed and the mother felt something was wrong, but had no clue."

Discussion Our study of the tacit knowledge of ​art​ therapists about their work with ​children​ with ASD has resulted in new insights on a descriptive level that we organized in a theoretical framework, the COAT model. There was substantial agreement among respondents regarding essential elements of ​art​ ​therapy​ with these ​children​, despite their diversity in methods and personalities as well as the differences in the ​children they worked with. This is promising for the development of a treatment protocol (Robey, 2004). According to the perceptions and experiences of respondents, ​art​ ​therapy​ could have an effect on reducing behavioral problems of ​children​ with autism in specific problem areas, including social communicative behavior, flexibility, and self-image. ​Art​ ​therapy interventions promote facilitating sensory experiences, sharing experiences, focusing attention, and talking about personal issues, and were reported to contribute to positive changes in behavior, not only during therapeutic sessions but also at home and in the classroom. Other authors have reported similar experiences (Emery, [13]; Gilroy, [15]; Pioch, [32]; Teeuw, [50]). Schweizer et al. ([43]) also found comparable behavioral and attitudinal approaches of the therapists themselves. These included active structuring, verbal and nonverbal attunement, and talking about experiences in ​art​ and in daily life. There seem to be positive influences on the ​child​ when parents, other family members, educators, and teachers are involved (Schothorst et al., [40]; Verheij, Westermann, & Maurer, [53]). However, working collaboratively with parents was not an issue mentioned by our respondents, although, according to some of the comments in the outcomes category of the COAT model, there was mention of contacts between the ​art therapist and the parents. This is different from what is recommended in academic and clinical literature with regard to engaging parents or caregivers (Renty & Roeyers, [35]; Simpson, [44]; Whitaker, [54]). The COAT model shown in Figure 1 organizes and summarizes the data, and contains four layers, thereby emphasizing the interplay of ​children's​ expressions, therapists' approaches, contextual conditions, and outcomes. Simpson ([44]), in his evaluative assessment of interventions and treatments for young people with ASD, distinguished four categories as a main treatment focus: the physical (e.g., sensory experiences), the cognitive (learning), the behavioral (skills), and the interpersonal (relationship)

dimensions. It is interesting to note that, in contrast to most other interventions in the Simpson overview, ​art​ ​therapy​ does not seem to have one exclusive focus. Considering respondents' answers, they seem to view ​art​ ​therapy​ as a multifocal intervention, thereby directing themselves to engage the physical (sensory), cognitive, and behavioral aspects of the ​child's​ functioning, as well as the relational aspects of the ​therapy​. Considering some of the problems of ​children​ with ASD in information processing related to theory of mind, executive functioning, and central coherence (Rozga et al., [38]), the question remains: To what extent does ​art​ ​therapy​ help to solve these problems? As respondents reported, the ​child​ develops communicative skills through art​ making that transfer to other situations. Despite theory of mind difficulties, ​art therapy​ appears to stimulate developmental possibilities. ​Art​ making also seems to activate planning skills (executive functioning). Finally, regarding central coherence, the varied sensory experiences of ​children​ in ​art​ ​therapy​ can be interpreted as stimulating the focusing of attention and broadening of their repertoire of preferences. Tacit knowledge of the experts we interviewed was systematically brought to the surface. The tacit knowledge that emerged in this study has resulted in coherent and plausible findings, thereby outlining crucial, practice-based elements and conditions for art​ ​therapy​ with ​children​ with ASD, fulfilling Martin's ([25]) emphasis that more empirical findings about ​art​ ​therapy​ and ASD are needed. Together with the results of a systematic review of clinical case descriptions on ​art​ ​therapy​ with these children​(Schweizer et al., [43]), an important step has been taken toward identifying what works in ​art​ ​therapy​with ​children​ with autism. This study is a step toward developing an evidence-based intervention. We developed the COAT model using some elements comparable with intervention mapping techniques (Bartholomew, Parcel, Kok, & Gottlieb, [ ​4​]). These techniques imply that an intervention is described in terms of its core aspects at a microlevel (what's being done in ​therapy​), its systemic and institutional aspects at a mesolevel (what institutional conditions are key), and its position in a scientific and societal context (what is the evidence of benefits and costs) at a macrolevel. The study also has limitations. First, differences in features of ​children​ with ASD and their problems were not taken into account explicitly. No ​child​ with ASD is equal to another (Fein, 2011; Nieweg, [29]). Although there was a certain amount of agreement in respondents' treatment experiences, they provided varied descriptions of ​children's behavior and expressions in ​art​. For instance, sometimes the ​art​ product was the main focus during treatment, and other times the shaping process was central. Some children​ have the ability for symbolic expression and understanding; others express themselves through prerepresentative shaping and body language. This means that the bottom-up approach of this study has yielded more detailed information about the

treatment provided by ​art​ therapists. At the same time, though, due to our method, individual differences of ​children​ with ASD to a certain level have disappeared. A second limitation is the small sample size and that it was studied in only one country, which provides a poor level of external validity. As our first goal was to detect crucial ​art therapeutic elements and components, more than producing a picture of the way ​art therapists interact with ASD ​children​ in the Netherlands, concordant experiences from all participating ​art​ therapists were pivotal (Mason, [26]). A final limitation is that we lack data about unsuccessful treatments, as well as factors that contributed to unsuccessful treatments. An explicit dialogue on this topic with respondents could have deepened our insights. Despite these limitations these expert practitioners contributed their rich experiences on promising components of ​art​ ​therapy​ treatment of ​children​ with ASD that we used to develop the COAT model. Each of the concepts in the model needs further elaboration. When building evidence about treatment, the concepts described in this article need to be further operationalized and standardized. One way to achieve this could be aimed at finding consensus on the most and least significant components or practice elements (Chorpita, Daleiden, & Weisz, [ ​9​]) with a Delphi procedure (e.g., Busschers, Boendermaker, & Dinkgreve, [ ​7​]). A second could be directed at observing and measuring ​art​therapists' behavior during sessions. A methodology that maps behavior as assessed by self-reports or external observations, based on a fixed checklist of therapeutic activities, could be used (Tausendfreund et al., 2015). Third, ​children's​, parents', and referrers' perspectives about COAT concepts can add useful information to compare to the therapists' responses from our study (Iachini, Hock, Thomas, & Clone, [18]); this would consider the multiple perspectives on the quality of ​art​ ​therapy (Raban, Ure, & Waniganayake, [34]). This study contributes to transparency, transferability, and professionalizing of ​art therapy​ with ​children​with ASD. Exploration and explication of tacit knowledge of ​art therapists, organized in the COAT model, is a first step toward a practice-based theoretical description of ​art​ ​therapy​ with autistic ​children​ (Van Yperen & Veerman, [51]).

Acknowledgments This research was completed to fulfill requirements for the first author's doctoral degree at Rijks University Groningen, Groningen, The Netherlands. This article could never be published without the help of the ​art​ therapists who were so helpful to share their practice experiences. Thanks a lot for their contributions.

References

1​ American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing. 2​ Babbie, E. (2001). The practice of social research (9th ed.). Belmont, CA: Wadsworth Thomson. 3​ Baron-Cohen, S. (2000). Theory of mind and autism: A fifteen year review. In S. Baron-Cohen, H. Tager-Flusberg, & D. J. Cohen (Eds.), Understanding other minds: Perspectives from developmental cognitive neuroscience (pp. 3–20). New York, NY: Oxford University Press. 4​ Bartholomew, L. K., Parcel, G. S., Kok, G., & Gottlieb, N. (2001). Intervention mapping. Designing theory- and evidence-based health promotion programs. New York, NY: McGraw-Hill. 5​ Boendermaker, L., Harder, A. T., Speetjens, P., Van der Pijll, M., Bartelink, C., & Van Everdingen, J. (2007). Programmeringsstudie Jeugdzorg [Programming study on ​child and youth care]. Utrecht/Groningen, The Netherlands: Dutch Youth Institute (NJi)/University of Groningen. 6​ Bryant, A., & Charmaz, K. (2007). The Sage handbook of grounded theory. Los Angeles, CA: Sage. 7​ Busschers, I., Boendermaker, L., & Dinkgreve, M. A. H. M. (2016). Validation and operationalization of intensive family case management: A Delphi study. ​Child​ and Adolescent Social Work Journal, 33(1), 69–78. doi:10.1007/s10560-015-0403-7 8​ Charmaz, K. (2006). Constructing grounded theory: A practical guide through qualitative analysis. London, UK: Sage. 9​ Chorpita, B. F., Daleiden, E. L., & Weisz, J. R. (2005). Identifying and selecting the common elements of evidence-based interventions: A distillation and matching model. Mental Health Services Research, 7(1), 5–20. doi:10.1007/s11020-005-1962-6 De Bildt, A. A., Blijd-Hoogerwijs, E. M. A., Dijkstra, S. P., Huizinga, P., Ketelaars, C. E. J., Kraijer, D. W., ... Minderaa, R. B. (2007). Pervasieve ontwikkelingsstoornissen [Pervasive developmental disorders]. In F. Verheij, F. C. Verhulst, & R. F. Ferdinand (Eds.), Kinder- en jeugdpsychiatrie; behandeling en begeleiding (pp. 31–81). Assen, The Netherlands: Van Gorcum. Doreleijers, T., Boer, F., Huisman, J., Vermeiren, R., & De Haan, E. (Eds.). (2006). Leerboek psychiatrie, kinderen en adolescenten [Handbook of psychiatry, ​children​ and adolescents]. Utrecht, The Netherlands: De Tijdstroom. Elkins, D. E., & Deaver, S. P. (2010). American ​Art​ ​Therapy​ Association, Inc.: 2009 membership survey report. ​Art​ ​Therapy​: Journal of the American ​Art​ ​Therapy Association, 27, 141–147. doi:10.1080/07421656.2010.10129665 Emery, M. J. (2004). ​Art​ ​therapy​ as an intervention for autism. ​Art​ ​Therapy​: Journal of the American ​Art​ ​Therapy​ Association, 21, 143–147. doi:10.1080/07421656.2004.10129500

Fein, D. A. (Ed.). (2011). The neuropsychology of autism. Oxford / New York: Oxford University Press. Gilroy, A. (2006). ​Art​ ​therapy​, research and evidence based practice. London, UK: Sage. Glaser, B. G., & Strauss, A. L. (1995). The discovery of grounded theory: Strategies for qualitative research. New Brunswick, NJ: Aldine. Happé, F., & Frith, U. (2006). The weak central coherence account: Detail-focused cognitive style in autism spectrum disorders. Journal of Autism and Developmental Disorders, 36(1), 5–25. doi:10.1007/s10803-005-0039-0 Iachini, A. L., Hock, R. M., Thomas, M., & Clone, S. (2015). Exploring the youth and parent perspective on practitioner behaviors that promote treatment engagement. Journal of Family Social Work, 18, 57–73. doi:10.1080/10522158.2014.974293 Kaiser, D., & Deaver, S. (2013). Establishing a research agenda for ​art​ ​therapy​: A Delphi study. ​ArtTherapy​: Journal of the American ​Art​ ​Therapy​ Association, 30, 112–121. doi:10.1080/07421656.2013.819281 Kenet, T. (2011). Sensory functions in ASD. In D. Fein (Ed.), The neuropsychology of autism (pp. 215–224). New York, NY: Oxford University Press. Korthagen, F. A. J., Kessels, J., Koster, B., Lagerwerf, B., & Wubbels, T. (2001). Linking practice and theory: The pedagogy of realistic teacher education. Mahwah, NJ: Erlbaum. Linesch, D., Aceves, H. C., Quezada, P., Trochez, M., & Zuniga, E. (2012). An ​art therapy​ exploration of immigration with Latino families. ​Art​ ​Therapy​: Journal of the American ​Art​ ​Therapy​ Association, 29, 120–126. doi:10.1080/07421656.2012.701603 Lucangeli, D. (2007). Voorlopers van metarepresentatie bij kinderen met autisme [Precursors of metarepresentation in ​children​ with autism]. In I. Noens & R. van IJzendoorn (Eds.), Autisme in orthopedagogisch perspectief (pp. 104–114). Amsterdam, The Netherlands: Boom Academic. Malchiodi, C. A. (2003). Handbook of ​art​ ​therapy​. New York, NY: Guilford. Martin, N. (2009). ​Art​ ​therapy​ and autism: Overview and recommendations. ​Art Therapy​: Journal of the American ​Art​ ​Therapy​ Association, 26, 187–190. doi:10.1080/07421656.2009.10129616 Mason, M. (2010). Sample size and saturation in PhD studies using qualitative interviews. Forum Qualitative Sozialforschung, 11(3), Article 8. Metzl, E. S. (2015). Holding and creating: A grounded theory of ​art​ ​therapy​ with 0–5-year-olds. International Journal of ​Art​ ​Therapy​, 20(3), 93–106. doi:10.1080/17454832.2015.1076015 Mottron, L., Dawson, M., Soulières, I., Hubert, B., & Burack, J. (2006). Enhanced perceptual functioning in autism: An update, and eight principles of autistic perception.

Journal of Autism and Developmental Disorders, 36(1), 27–43. doi:10.1007/s10803-005-0040-7 Nieweg, E. (2013). DSM, een zoektocht naar fantomen [DSM, a search for phantoms]. Medisch Contact, 69, 1052–1055. Ozonoff, S., Pennington, B. F., & Rogers, S. J. (1991). Executive function deficits in high-functioning autistic individuals: Relationship to theory of mind. Journal of ​Child Psychology and Psychiatry, 32, 1081–1105. doi:10.1111/j.1469-7610.1991.tb00351.x Pénzes, I., Van Hooren, S., Dokter, D., Smeijsters, H., & Hutschemaekers, G. (2014). Material interaction in ​art​ ​therapy​ assessment. The ​Arts​ in Psychotherapy, 41, 484–492. doi:10.1016/j.aip.2014.08.003 Pioch, A. (2010). Vaktherapie in een leeromgeving: Projectverslag en onderzoekstraject [​Arts​ ​therapies​in a learning community: Report and research plan]. Groningen, The Netherlands: RENN4, Vaktherapie/Sensor. Polanyi, M. (1967). The tacit dimension. London, UK: Routledge. Raban, B., Ure, C., & Waniganayake, M. (2003). Multiple perspectives: Acknowledging the virtue of complexity in measuring quality. Early Years: An International Research Journal, 23(1), 67–77. doi:10.1080/0957514032000045591 Renty, J., & Roeyers, H. (2006). Satisfaction with formal support and education for children​ with autism spectrum disorder: The voices of the parents. ​Child​: Care, Health and Development, 32, 371–385. doi:10.1111/j.1365-2214.2006.00584.x Richard, D. A., More, W., & Joy, S. P. (2015). Recognizing emotions: Testing an intervention for ​children​with autism spectrum disorders. ​Art​ ​Therapy​: Journal of the American ​Art​ ​Therapy​ Association, 32, 13–19. doi:10.1080/07421656.2014.994163 Robey, R. R. (2004). A five-phase model for clinical-outcome research. Journal of Communication Disorders, 37(5), 401–411. doi:10.1016/j.jcomdis.2004.04.003 Rozga, A., Andersson, S. A., & Robons, D. L. (2011). Major current neuropsychological theories of ASD. In D. Fein (Ed.), The neuropsychology of autism (pp. 97–120). New York, NY: Oxford University Press. Rubin, J. (2001). Approaches to ​art​ ​therapy​: Theory and technique. New York, NY: Routledge. Schothorst, P. F., Van Engeland, H., Van der Gaag, R. J., Minderaa, R. B., Stockmann, A. P. A. M., Westermann, G. M. A., ... Ketelaars, C. E. J. (2009). Richtlijn diagnostiek en behandeling Autisme Spectrum Stoornissen bij kinderen en jeugdigen [Guideline on assessment and treatment of autism spectrum disorders in ​children​ and adolescents]. Utrecht, The Netherlands: de Tijdstroom. Schweizer, C. (2014). Beeldende therapie bij kinderen met een Autisme Spectrum Stoornis [​Art​ ​therapy​with ​children​ with autism spectrum disorders]. Wetenschappelijk Tijdschrift Autisme, 13(1), 28–35.

Schweizer, C., De Bruyn, J., Haeyen, S., Henskens, B., Rutten-Saris, M., & Visser, H. (Eds.). (2009). Handboek beeldende therapie. Uit de verf [Handbook of ​art​ ​therapy​: Painted out]. Houten, The Netherlands: Bohn Stafleu van Loghum. Schweizer, C., Knorth, E. J., & Spreen, M. (2014). ​Art​ ​therapy​ with ​children​ with autism spectrum disorders: A review of clinical case descriptions on "what works." The Arts​ in Psychotherapy, 41, 577–593. doi:10.1016/j.aip.2014.10.009 Simpson, R. L. (2005). Evidence-based practices and students with autism spectrum disorders. Focus on Autism and Other Developmental Disabilities, 20, 140–149. doi:10.1177/10883576050200030201 Slayton, S. C., D'Archer, J., & Kaplan, F. (2010). Outcome studies on the efficacy of ​art therapy​: A review of findings. ​Art​ ​Therapy​: Journal of the American ​Art​ ​Therapy Association, 27, 108–118. doi:10.1080/07421656.2010.10129660 Smeijsters, H. J. M., & Cleven, G. (2006). The treatment of aggression using ​arts therapies​ in forensic psychiatry: Results of a qualitative inquiry. The ​Arts​ in Psychotherapy, 33(1), 37–58. doi:10.1016/j.aip.2005.07.001 Strauss, A., & Corbin, J. (1998). Basics of qualitative research techniques and procedures for developing grounded theory (2nd ed.). London, UK: Sage. Swaab, H. (2007). Neuropsychologie en neuropedagogiek bij Autisme Spectrum Stoornissen [Neuropsychology and neuropedagogy in case of autism spectrum disorders]. In I. Noens & R. van IJzendoorn (Eds.), Autisme in orthopedagogisch perspectief (pp. 92–103). Amsterdam, The Netherlands: Boom Academic. Tausendfreund, T., Metselaar, J., Conradie, J., De Groot, M. H., Schipaanboord, N., Knot-Dickscheit, J., ... Knorth, E. J. (2015). Self-reported care activities in a home-based intervention programme for families with multiple problems. Journal of Children's​ Services, 10(1), 29–44. doi:10.1108/JCS-07-2014-0034 Teeuw, H. (2011). Resultaten in beeld: Onderzoekslijn procesevaluatie. Een onderzoek naar resultaten die beeldend therapeuten behalen bij kinderen met PDDnos van 8–12 jaar [Outcomes in the picture: Research program process-evaluation. A study on outcomes of ​art​ therapists working with 8–12 years aged ​children​ diagnosed with PDDnos] (Unpublished bachelor's thesis). Stenden University of Applied Sciences, Leeuwarden, The Netherlands. Van Yperen, T. A., & Veerman, J. W. (Eds.). (2008). Zicht op effectiviteit. Handboek voor praktijkgestuurd effectonderzoek in de jeugdzorg [A view on effectiveness: Handbook of practice-based research on outcomes in ​child​ and youth care]. Delft, The Netherlands: Eburon. Veerman, J. W., & Van Yperen, T. A. (2007). Degrees of freedom and degrees of certainty: A developmental model for the establishment of evidence-based youth care. Evaluation and Program Planning, 30, 212–221. doi:10.1016/j.evalprogplan.2007.01.011

Verheij, F., Westermann, G. M. A., & Maurer, J. M. G. (2014). Adviseren en plannen van jeugdhulp [Advising on and planning of youth care]. Amsterdam, The Netherlands: SWP. Whitaker, P. (2002). Supporting families of preschool ​children​ with autism: What parents want and what helps. Autism, 6, 411–426. doi:10.1177/1362361302006004007 ~~~~~~~~ By Celine Schweizer; Marinus Spreen and Erik J. Knorth Reported by Author; Author; Author Celine Schweizer is a doctoral candidate at Rijks University, Groningen, The Netherlands, and a Lecturer at Stenden University of Applied Sciences in Leeuwarden, The Netherlands. Marinus Spreen is a Professor at Stenden University of Applied Sciences in Leeuwarden, The Netherlands. Erik J. Knorth is a Professor at Rijks University Groningen, Groningen, The Netherlands. Celine Schweizer is a doctoral candidate at Rijks University, Groningen, The Netherlands, and a Lecturer at Stenden University of Applied Sciences in Leeuwarden, The Netherlands. Marinus Spreen is a Professor at Stenden University of Applied Sciences in Leeuwarden, The Netherlands. Erik J. Knorth is a Professor at Rijks University Groningen, Groningen, The Netherlands. Celine Schweizer is a doctoral candidate at Rijks University, Groningen, The Netherlands, and a Lecturer at Stenden University of Applied Sciences in Leeuwarden, The Netherlands. Marinus Spreen is a Professor at Stenden University of Applied Sciences in Leeuwarden, The Netherlands. Erik J. Knorth is a Professor at Rijks University Groningen, Groningen, The Netherlands.