BACKGROUND: Children with communication impairments-such as autism spectrum disorder or global developmental delay-face significant challenges affecting their emotional and behavioural development. The Picture Exchange Communication System (PECS) is an augmentative communication tool designed to enhance their skills. However, its effectiveness can vary in resource-limited settings. This study aimed to identify predictors of successful PECS training among children with communication impairments in such environments. METHODS: This retrospective study analysed records of 61 children with communication impairments who underwent PECS training at Siriraj Hospital in Bangkok, Thailand, from 2020 to 2023. Success was defined as achieving PECS phase 3 proficiency and a Clinical Global Impression-Improvement score of 1-3 after 1 year. Logistic regression identified predictors of successful outcomes based on demographic, clinical, family and training-related factors. RESULTS: After 1 year, 46% (28 out of 61) of the children achieved successful PECS outcomes. Significant predictors of success were lower severity of communication impairment (Clinical Global Impression-Severity ≤4
adjusted OR= 15.24, p = 0.002), higher frequency of PECS sessions (>
6 times per year
OR = 9.11, p = 0.010), higher family income (≥20,000 baht per month
OR = 9.83, p = 0.024) and frequent home practice (≥3 times per week
OR = 7.02, p = 0.066). CONCLUSIONS: In resource-limited settings, factors such as severity of impairment, intensity of intervention, socioeconomic status and caregiver involvement significantly influence the success of PECS training. Tailored interventions and strategic resource allocation are crucial to optimise communication outcomes for these children.