Efficacy and moderating factors of the Early Start Denver Model in Chinese toddlers with autism spectrum disorder: a longitudinal study.

Background: Several studies have shown the effectiveness of the Early Start Denver Model (ESDM), but few studies have explored the long-term efficacy of ESDM. This study aimed to explore the efficacy and moderating factors of ESDM in Chinese toddlers with autism spectrum disorder (ASD) in a longitudinal way.

Methods: A total of 60 toddlers with ASD were recruited and randomly divided into two groups: ESDM group all received 24 weeks intervention; Control group were waiting for intervention. Baseline assessment (T0) was conducted before intervention, including Gesell Developmental Scale (GDS) and Psycho-educational Profile-3rd Edition (PEP-3). All toddlers with ASD were examined in the first assessment (T1) at 6 months and in the second assessment (T2) at 12 months.

Results: In T1 assessment, the increments in speech and personal communication development quotient in GDS were significantly larger in the ESDM group than in the control group (P = 0.010, 0.047). In T2 assessment, the ESDM group had higher elevation in cognitive verbal/preverbal (CVP), social reciprocity and characteristic verbal behaviors assessed by PEP-3 (P = 0.021, 0.046, 0.014). In addition, the severity of stereotyped behavior was negatively associated with improvement in CVP. Family income was positively associated with improvement in speech and CVP (all P < 0.05).

Conclusions: ESDM can effectively improve speech and communication in toddlers with ASD after 24-week intervention. More importantly, ESDM can promote cognition and social interaction and can reduce stereotyped verbal behavior in toddlers with ASD in longitudinal observation. The severity of stereotyped behavior and family ecological factors may be considered as affecting the efficacy of ESDM.