Objectives: To estimate the prevalence of autism spectrum disorder (ASD) among 18-36 month old children in the Tianjin municipality of China, and to identify early signs of autistic children and how predictive each symptom will be.
Methods: 8000 children aged 18-36 months were screened using a multi-stage stratified sampling procedure and questionnaire based on the Checklist for Autism in Toddlers (CHAT) modified to include early signs of autism. Then we followed the 367 at-risk children and 22 were identified as having ASD on the basis of the Childhood Autism Rating Scale (CARS) and DSM-IV. Discriminant function analysis was performed between ASD children, children not followed up on (group A) and children followed up on but not meeting ASD criteria (group B) to identify early signs of autistic children.
Results: The prevalence of ASD among 18-36 month old Chinese children was 27.5 per 10,000. Items addressing social interaction and communication, e.g. pointing with finger, gaze monitoring, eye contact, age of first smile, interest in peers, obedience to simple instructions, spoken language had higher weight than other items to distinguish autistic children from both group A and group B. Autistic children showed significant differences from group A, but not group B on pretend play, functional play, and showing and reading parents’ facial expressions.
Conclusions: The prevalence of autism spectrum disorder found in our study is lower than the results from previous western studies, but higher than the former study in the same region. Autism has its specific symptoms, such as deficits in social awareness, social relatedness, and social referencing.
See more of: Epidemiology
See more of: Prevalence, Risk factors & Intervention