The quality of the learning environment in preschool is of significant importance for children with autism spectrum disorder (ASD). However, very limited research has addressed how this environment can be improved. In regard to early intervention, most previous studies have primarily focused on child characteristics, and intervention content and quantity, rather than the broader learning environment in which interventions are delivered. Thus, the overall aim of this thesis was to study the quality of the learning environment for children with ASD. In particular, the focus was on children who receive Early Intensive Behavioral Intervention (EIBI) in community-based Swedish preschools, using the Autism Program Environment Rating Scale (APERS). Within this framework, three studies were conducted.

In study 1, we translated, culturally adapted, and systematically assessed the content validity of APERS, a rating scale designed to assess the program quality for children with ASD in educational settings. In the process, the scale was modified to make the instrument as relevant as possible for the Swedish preschool context, and re-named APERS-P-SE. Nine experts rated the clarity and comprehensiveness of the individual items, as well as the relevance of the scale in its entirety. In study 2, we evaluated APERS-P-SE as the foundation for professional development for preschool staff working with children with ASD receiving EIBI, to promote preschool learning environment quality (primary outcome), and outcomes for autistic children, and preschool staff (secondary outcomes). Using a quasi-experimental design, preschool staff either implemented EIBI enriched by in-service training and on-site coaching based on APERS-P-SE assessments (k = 9), or EIBI only (k = 8) during 8 months. A total of 17 children and 35 preschool staff participated, across 17 preschools. In study 3, individual interviews and focus-group interviews were conducted with preschool staff, preschool principals, habilitation supervisors, and parents to children with ASD who had participated in study 2 and received the APERS-P-SE-based intervention. Through these interviews, the different groups of stakeholders provided their thoughts about what they found to be the most important aspects of preschool programs for autistic children who receive EIBI, and their opinions and experiences of participating in study 2.

 Study 1 demonstrated a high level of content validity for the Swedish version of the APERS. In study 2, the EIBI/APERS-P-SE preschools significantly improved their learning environment, compared to the preschools that received EIBI only. Outcomes for autistic children and preschool staff did not differ significantly between the groups, despite positive descriptive findings. In study 3, four themes were identified as being key aspects of preschool programs with high quality to promote optimal development of children with ASD: (1) staff’s competence, (2) children’s inclusion and participation, (3) collaboration, and (4) learning environment. Overall, the stakeholders described the APERS-P-SE-based model as helpful in improving children’s participation, preschool staff’s engagement with the child, and optimizing child outcomes.

Taken together, the results indicate that APERS-P-SE is an instrument with a high level of content validity, and that it can be used in combination with in-service training and on-site coaching to improve preschool program quality for children with ASD.