*3.7.3. Review of literature*

As TEACCH was developed and has training facilities housed within the University of North Carolina at Chapel Hill, there are researchers embedded in the program who have worked to establish a strong research base. When analyzing efficacy, it is important to identify potential bias that might occur by reviewing studies conducted only by researchers working where the technique was developed. To avoid that bias, a number of studies from within and outside the University of North Carolina at Chapel Hill were reviewed.

A meta-analysis of intervention studies using TEACCH (level 1 evidence) was conducted by Virues-Ortega, Julio, and Pastor-Barriuso in 2013 [68]. This meta-analysis utilized 13 studies, with a combined sample of 172 children diagnosed with ASD, assessing perceptual and motor skills, adaptive behaviors, and language and cognition. Results indicated that TEACCH had a small magnitude impact on perceptual, motor, verbal and cognitive skills, a negligible impact on communication, activities of daily living, and motor functioning, and moderate to large gains in social behavior and maladaptive behavior. The overall effect of the TEACCH program on all the outcomes measured in the meta-analysis was moderate, with effects in older children being higher than those in younger children. The authors cautioned that while these findings indicate success with TEACCH, the small number of studies and sample size should be considered.

D'Elia and associates conducted a longitudinal study of low-intensity TEACCH in preschool aged children [65]. The study followed a sample of 30 children, aged 2–6.11 years, diagnosed with autistic disorder or pervasive developmental disorder – not otherwise specified over a 2 year period. The group was split evenly into a control group that did not receive TEACCH and an experimental group that received the TEACCH intervention 2 h per week at school and 2 h per week at home. Results for the main outcome indicators of severity of autism, language, and adaptive functioning showed no significant difference between the control group and the experimental group. Results for the secondary outcomes of parental stress and psychopathological comorbidity indicated significant differences between the control group and the experimental group. Both secondary outcomes indicated greater improvement in the experimental group. The authors indicate that the lack of significance in primary outcomes could possibly be attributed to the low intensity of the TEACCH intervention, which is not standard protocol. The positive secondary outcomes indicate potential of the TEACCH program in decreasing parental stress and child behavioral/emotional problems.

With home-based TEACCH being a major component of the program, it is important to determine the efficacy of that particular approach. Weterlin and associates conducted a study on the efficacy of the Home-TEACCHing Program (HTP) on toddlers with ASD [67]. The sample included twenty 2–3 year old children and their parents. Children and their parents were randomly assigned to either the treatment (HTP) group or the waitlist (WL) group. WL group members were informed that they would receive the treatment at the conclusion of a 12 week wait period. This study yielded three major findings: (1) HTP improved children's independent work skills; (2) Parents were able to structure the physical environment to improve child outcomes; (3) Parents improved their effective prompting, including using visual prompts. Although the sample size was small, findings demonstrate support for the use of the Home-TEACCHing Program.

Overall, research to date on effectiveness of the TEACCH program is very encouraging. Therapists use the components of TEACCH to assist children with ASD in learning tasks. Specifically, therapists using this technique will structure the physical environment (including visual cues), and organize the task with explicit directions in order to assist the child in learning new skills that aid in improved functional outcomes.
