Abstract: Objective To explore the relationship between infant sociality performance at the ages of 3-12 months and the occurrence of autism spectrum disorders (ASDs) at the age of 18 months.Methods Totally 1 207 infants aged 3 months(±7 days)at the enrollment were recruited at Maanshan Municipal Instruction Center for Community Health Service for a prospective cohort study from March through October 2012.Infant Sociality Performance Questionnaire (ISPQ) was applied to assess sociality performance of the infants at the ages of 3,6,9,and 12 months;the ISPQ scores of the infants at different ages were calculated and then the infants were assigned into the low- (1-25 percentile),medium-(26-75 percentile),and high-(76-100 percentile)score groups according their ISPQ scores.Checklist for Autism in Toddlers (CHAT-23) was adopted to screen ASDs among the infants at the age of 18 months.Chi-square analysis and binary logistic regression analysis were performed in data analyses.Results Of all infants enrolled,1 085 were followed up to their 18 months of age and 99 were identified as suspected ASDs,with an overall detection rate of 9.1%.Among the infants with low ISPQ scores at the ages of 3,6,9,and 12 months,the detection rates of ASDs were 16.1%,13.3%,13.7%,and 14.5%,respectively.The results of Chi-square analysis showed that compared to the infants with high ISPQ score,those with low ISPQ score had a higher prevalence of ASDs.Binary logistic regression analyses showed that the low ISPQ score was a risk factors for ASDs in early childhood,with the relative risk (RR) and its 95%confidence interval (95%CI) of 2.94 (1.50-5.75),3.28 (1.32-8.09),2.38 (1.16-4.88),and 4.90 (2.08-11.49) for the infants at the ages of 3,6,9,and 12 months,respectively.Conclusion The results suggest that early sociality performance may be a predictor of incident of ASDs and may provide evidences for early diagnosis and treatment of the disease.