Evaluating the effectiveness of DIR/Floortime intervention on two-way purposeful communication skills in a child with autism spectrum disorder: a single-subject study

The Developmental, Individual-Difference, Relationship-Based (DIR/Floortime) model is a play-based, relationship-focused developmental approach that is widely used to support social and communicative development in children with Autism Spectrum Disorder (ASD). Purposeful two-way communication is often delayed in children with ASD. Despite strong international evidence, research on DIR/Floortime in Türkiye remains limited. A single-subject AB design was conducted with a four-year-old male child with ASD attending a public preschool for special education in Bartın, Türkiye to examine preliminary intervention-related changes. Baseline data were collected over three sessions across two weeks. The intervention consisted of eight 20-minute sessions over four weeks (two sessions per week), targeting the first three functional emotional developmental capacities. The primary outcome was the longest uninterrupted sequence of completed communication circles achieved during each session, with the performance criterion defined as at least 10 consecutive completed communication circles across three consecutive intervention sessions. Data were collected using the DIR/Floortime Checklist, social validity forms, and reliability measures. Follow-up sessions were conducted at two, four, and six weeks post-intervention, and generalization was assessed by a different practitioner. Results showed an increase in the longest uninterrupted sequence of completed communication circles from a maximum of one at baseline to 14 during intervention. Skills were maintained at follow-up (11–12 circles) and generalized successfully (13–14 circles). Reports from the teacher and the mother supported the social validity of the intervention, suggesting preliminary evidence for integrating DIR/Floortime into early intervention practices in Türkiye.