Background: Children with intellectual and developmental disabilities (IDD) are at higher risk of
exhibiting challenging behaviours (CB). Positive behaviour support interventions like the
Prevent–Teach–Reinforce (PTR) school-based model, have demonstrated effectiveness in reducing
CB and promoting appropriate behaviours (AB) among students with persistent CB in mainstream
schools; however, evidence with students who have extensive support needs in special
school settings remains limited.
Objectives and method: This single-case experimental study with multiple baselines across participants
assessed the effects and social validity of the PTR for four students with IDD in special
schools.
Results: Implementation was associated with overall reductions in CB and increases in AB,
although effects for some students were more apparent during the maintenance phase than
during the intervention phase. Variability in behaviour and baseline trends were observed, highlighting
the importance of multi-source measurement and ongoing monitoring. Teachers were
able to implement PTR intervention plans without prior training and reported high treatment
acceptability.
Conclusion: Findings suggest that implementing PTR for students with IDD, CB, and extensive
support needs in special schools is both feasible and promising. Results highlight the value of
structured coaching and attention to contextual factors in intervention planning.