Efficacy of the Picture Exchange Communication System for children with autism in Mainland China: A systematic review and meta-analysis of randomized controlled trials

Objective This systematic review and meta-analysis aimed to investigate the efficacy of the Picture Exchange Communication System (PECS) in improving communication skills and related collateral outcomes among children with autism in Mainland China, and to identify potential moderators. Methods Following PRISMA 2020 guidelines, seven databases were searched from inception to July 31, 2025 for randomized controlled trials (RCTs) on PECS for children with autism in Mainland China. Pooled standardized mean differences (SMD) with 95 % confidence intervals (CI) were calculated using random-effects models. Sensitivity and subgroup analyses assessed heterogeneity and robustness. Results Thirty-seven RCTs were included (34 in meta-analysis; n = 2343). PECS demonstrated a large, significant overall effect (SMD = 0.95, 95 % CI: 0.76, 1.13), with substantial improvement in communication skills (SMD = 0.94, 95 % CI: 0.67, 1.21) and notable collateral benefits for cognitive function (SMD = 2.46), core autistic symptoms (SMD = 1.62), health-related quality of life (SMD = 0.91), social skills (SMD = 0.88), maladaptive behaviors (SMD = 0.83), mental health (SMD = 0.73), and motor skills (SMD = 0.55). No significant effect was found for language development (SMD = 0.44, 95 % CI: − 0.53, 1.41). Interventions delivered by medical professionals in clinical settings demonstrated a significant and large effect (SMD = 0.92, 95 % CI: 0.74, 1.11), whereas the limited number of studies conducted in educational settings by educational professionals produced a larger point estimate but non-significant effects. No statistically significant moderation was detected for study population, economic region, intervention frequency, PECS phase, or study quality (all interaction tests non-significant). Conclusion PECS demonstrates a large and significant effect on communication skills and several collateral outcomes for children with autism in Mainland China, supporting its a promising, effective intervention.