Sensory-Based Approaches in Intervention for Children With Autism Spectrum Disorder: Influences on Occupational Therapists’ Recommendations and Perceived Benefits

Method

The University of Alberta Health Research Ethics Board approved this study. Participants were recruited through pediatric occupational therapy email groups and snowball sampling. Data collection occurred from January through June 2014 through a web-based survey hosted on the secure online platform Research Electronic Data Capture (REDCap; Harris et al., 2009). The survey included two parts: (1) detailed demographic information about the participants, their work experience, and training and (2) questions about their use, beliefs, and perceptions of sensory-based approaches (including the percentage of children with ASD with whom they used the interventions, the percentage for whom these approaches were effective, and the behaviors or outcomes they were effective in changing). (The survey is provided in Supplemental Appendix A, available online at http://otjournal.net; navigate to this article, and click on “Supplemental.”)

The survey took approximately 20 min to complete. Inclusion criteria were being a practicing occupational therapist currently working with at least one child with ASD (up to age 18) and being able to complete the survey in English.

Survey data were downloaded from REDCap to Microsoft Excel, screened for accuracy, and cleaned to remove unusable data. Twenty-six participant responses were removed because of insufficient data (e.g., completed only the demographic section). Data were analyzed using Stata (Version 13; StataCorp, College Station, TX). Descriptive statistics summarized current practice patterns related to sensory-based interventions.

Two multivariable linear regression models were built to examine the relationship between the predictor variables and two dependent variables: (1) percent recommended (i.e., percentage of children with ASD with whom they used sensory-based interventions) and (2) percent effective (i.e., percentage of children for whom sensory-based approaches were effective). Predictor variables were based on their theoretical relevance to the hypotheses. For example, evidence-based practice (EBP) includes clinical expertise, so mentorship and professional development were included in the model. Educational attainment was included on the basis of the premise that occupational therapists enroll in graduate studies beyond an entry-to-practice degree because of an interest in research.

Three steps, based on Hosmer, Lemeshow, and Sturdivant’s (2013) procedures for model building, were used for each model. In the first step, univariable models were built for each predictor variable and dependent variable to identify associations with p < .20. This significance level reduced the likelihood of missing important variables. Variables in Step 1 were country of residence, educational attainment, whether SI had been promoted in school, experience as an occupational therapist (years), postgraduation SI training, whether respondents had a mentor who promoted SI, whether they were Sensory Integration and Praxis Tests (SIPT; Ayres, 1989) certified, funding source, and whether they participated in direct treatment.

In the second step, a multivariable model was built including all significant variables in Step 1. Variables with p ≥ .05 were removed because they did not statistically contribute to the current model. In the third step, each variable was entered back into the model one at a time to see whether any β coefficients changed by 15% or more. If so, this variable was potentially associated and retained in the final model.

Results

Discussion

This study explored occupational therapists’ use of sensory-based approaches with children with ASD. Respondents recommended sensory-based approaches for about half of the children with ASD with whom they worked. They most often recommended sensory diets and weight or pressure modalities, followed by SI therapy and auditory therapies. Choosing these interventions may reflect therapists’ perspectives on how best to address the participation restrictions associated with ASD. These sensory-based approaches appear to address the sensory processing differences common in children with ASD and to target underlying mechanisms. As noted earlier, several reviews have concluded that some of these approaches have inconclusive support as EBP (e.g., Ashburner et al., 2014; Case-Smith & Arbesman, 2008; National Autism Center, 2015; Watling & Hauer, 2015). For instance, noncustomized sensory diets are not empirically supported (Tomchek & Koenig, 2016), although sensory diets vary in approach, including some that target factors external to the child. Our survey did not ask about specifics of the approaches used, such as the type of sensory diet.

Respondents chose non–sensory-based approaches for half of the children with whom they worked, but they were not asked to identify those approaches. Best practices in ASD intervention would indicate that respondents likely considered individual client and other contextual information and needs in their clinical decision making (National Autism Center, 2015). Respondents could identify other sensory-related approaches that they used; environmental modifications were reported by 3% of respondents and contextual interventions, such as changing task demands or aspects of the setting, were reported by 6%, although we think this is an underestimation of environmental and contextual approaches used. These approaches focus on factors external to the child and have empirical support for improving participation, decreasing disruptive behaviors, and improving family well-being (Ashburner et al., 2014; Cale, Carr, Blakeley-Smith, & Owen-DeSchryver, 2009). Future research needs to explore occupational therapists’ decision-making processes and identify the other approaches they use.

Factors associated with recommendation of sensory-based approaches included experience, country of residence, and mentorship, explaining 22% of the variance. Compared with more established occupational therapists, newer occupational therapists recommended these approaches for a smaller percentage of the children with ASD. Given the increasing prevalence of ASD, this practice trend may reflect greater awareness of EBP and the demand for more occupational therapists, including recent graduates, to provide services for clients with ASD. Working in a country outside of North America and Australia predicted increased use of and perceived benefit from sensory-based approaches. Perhaps there is something different in how other countries teach or view EBP, what occupational therapists learn about ASD, or the service delivery models primarily used in practice.

Mentorship predicted both use and perceived benefit of sensory-based approaches. Occupational therapists historically have emphasized knowledge from clinical expertise and colleagues over research evidence (Dubouloz, Egan, Vallerand, & von Zweck, 1999). SI has a strong history of clinical mentorship in particular (Miller-Kuhaneck, 2010). Even as practice has become more evidence based, occupational therapists working with people with ASD in general rely on evidence from clinical experience, colleagues, and presentations rather than research literature (Ashburner et al., 2014). It is important to consider why mentorship is a strong contributor to clinical reasoning in this area of practice compared with research evidence.

The volume of research about treatment choices for clients with ASD can be overwhelming, leading to information overload and reliance on word-of-mouth recommendations rather than research evidence for families and professionals (Matson, Adams, Williams, & Rieske, 2013). Furthermore, a distrust of science in the ASD field based on a history of aversive treatments, differing theories of cause, competing treatment approaches (Elsabbagh et al., 2014), and controversy around inconsistent findings, particularly related to SI and sensory-based approaches (Kadar et al., 2012), may influence uptake of research evidence into ASD practice. Specific to occupational therapy, occupational therapists often seek evidence that confirms current practice and may view new evidence as threatening (Ashburner et al., 2014; Dubouloz et al., 1999). Comfort in their current role combined with role expectations from clients and professional colleagues may reinforce status quo practices, especially for practitioners who have found that changing the status quo created conflict and tension in professional relationships.

Expectations may explain occupational therapists’ recommendations of sensory-based interventions. For example, parents and teachers may request weighted vests even though this modality has little or no effect (e.g., Watling & Hauer, 2015). The lack of perceived benefits for half of children for whom respondents have recommended sensory-based strategies suggests that something other than their perspective on the most beneficial approach may have influenced their clinical reasoning process and subsequent clinical recommendations. Alternatively, respondents reported positive outcomes in half of the children, which may represent a relatively rewarding success rate within the broader context of ASD treatment. The lack of current knowledge and evidence to predict which children may respond to an intervention and which will not likely reinforces the broad use of these interventions. Future research should investigate why occupational therapists who have mixed success with sensory-based modalities continue to use this approach.

An Australian study reported that occupational therapists found working with children with ASD to be challenging and lacked confidence in this area of practice (Kadar et al., 2012). Should these findings hold true in other locations, when combined with information overload, this lack of confidence may contribute to a heavy reliance on clinical expertise and mentorship, rather than empirical evidence, in making practice decisions. Relying on clinical expertise could create a cycle of practices in which (1) occupational therapists lack confidence about what to do with children with ASD, (2) these occupational therapists rely heavily on mentors with significant clinical experience, (3) mentors encourage their own status quo of practice based on comfort and external validation by families and colleagues of these practices (which likely primarily incorporate sensory-based approaches; Ashburner et al., 2014; Kadar et al., 2012; Watling et al., 1999), and (4) mentees go on to reinforce these practices in line with the mentorship they received. A study by Miller-Kuhaneck (2010) suggested that perpetuation of mentorship through subsequent generations of expert clinicians may be especially common with sensory-based practices such as SI. Parents of children with ASD prefer information from professionals and nonempirical sources to research evidence, further perpetuating these practices (Grant, Rodger, & Hoffmann, 2016). This is only one potential interpretation of mentorship processes in ASD practice, and it should be explored in future research.

Study Limitations and Directions for Future Research

We did not ask whether the occupational therapists used nonsensory approaches in combination with sensory-based approaches. Our findings do not fully represent practice patterns and clinical reasoning processes related to occupational therapists’ use of and beliefs regarding sensory-based approaches in ASD. Like all survey research, it is possible that our respondents were more likely to have stronger beliefs, both positive and negative, about sensory-based approaches in ASD than nonparticipants, skewing our data. For logistical reasons, our survey was limited to English-speaking therapists.

Our low adjusted R ²s (see Tables 3 and 4) suggest the presence of other unaccounted-for variables contributing to decisions related to sensory-based modalities or the possibility of a nonlinear relationship among these variables that we were unable to test because of the categorical nature of the variables. The sample size is relatively small relative to the number of predictor variables in traditional thinking related to regression analyses. However, power did not appear to be a problem because several variables in the final regression models were statistically significant, regression coefficients were fairly consistent between the uni- and multivariable analyses, and many of the confidence intervals were narrow. Together, these facts provide evidence that our final regression models were not overfit (with five variables entered for recommending and six for benefits).

Regardless of these limitations, delineating occupational therapists’ use of and beliefs about sensory-based practices, based on clinical predictors, has not been reported in previous studies. Therefore, this study contributes new knowledge to the field that can influence practice and occupational therapy education. A subsequent study that captures the nuances of occupational therapists’ clinical reasoning in this area is needed. It should address factors therapists consider in choosing a particular sensory-based intervention, which children with ASD they think would and would not benefit from sensory-based approaches and why, and how they incorporate sensory-based approaches with other interventions.

Implications for Occupational Therapy Practice and Research

The findings of this study have the following implications for occupational therapy practice:

Supplemental Material