title: Exploring the Underdiagnosis and Prevalence of Autism Spectrum Conditions in Beijing.
abstract: Previous studies reported that the prevalence of Autism Spectrum Conditions (ASC) in mainland China is much lower than estimates from developed countries (around 1%). The aim of the study is to apply current screening and standardized diagnostic instruments to a Chinese population to establish a prevalence estimate of ASC in an undiagnosed population in mainland China. We followed the design development used previously in the UK published in 2009 by Baron-Cohen and colleagues. The Mandarin Childhood Autism Spectrum Test (CAST) was validated by screening primary school pupils (n = 737 children age 6-10 years old) in Beijing and by conducting diagnostic assessments using the Autism Diagnostic Observation Schedule and the Autism Diagnostic Interview-Revised. The prevalence estimate was generated after adjusting and imputing for missing values using the inverse probability weighting. Response was high (97%). Using the UK cutoff (≥15), CAST performance has 84% sensitivity and 96% specificity (95% confidence interval [CI]: 46, 98, and 96, 97, respectively). Six out of 103 children, not previously diagnosed, were found to the meet diagnostic criteria (8.5 after adjustment, 95% CI: 1.6, 15.4). The preliminary prevalence in an undiagnosed primary school population in mainland China was 119 per 10,000 (95% CI: 53, 265). The utility of CAST is acceptable as a screening instrument for ASC in large epidemiological studies in China. Using a comparable method, the preliminary prevalence estimate of ASC in mainland China is similar to that of those from developed countries.
authors.affiliation: Department of Public Health and Primary Care, Cambridge Institute of Public Health, University of Cambridge, Cambridge, UK.|Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, UK.|Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK.
authors.forename: Xiang
authors.initials: X
authors.lastname: Sun
authors.affiliation: Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, UK.|Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK.
authors.forename: Carrie
authors.initials: C
authors.lastname: Allison
authors.affiliation: MRC Biostatistics Unit, Cambridge Institute of Public Health, Cambridge, UK.
authors.forename: Fiona E
authors.initials: FE
authors.lastname: Matthews
authors.affiliation: Pediatrics Department, Peking University First Hospital, Beijing, China.
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, UK.|Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK.|Department of Psychology, University of Edinburgh, Edinburgh, UK.
authors.forename: Bonnie
authors.initials: B
authors.lastname: Auyeung
authors.affiliation: Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, UK.|Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Baron-Cohen
authors.affiliation: Department of Public Health and Primary Care, Cambridge Institute of Public Health, University of Cambridge, Cambridge, UK.
authors.forename: Carol
authors.initials: C
authors.lastname: Brayne
mesh_terms: D000067877:Autism Spectrum Disorder / Q000175:diagnosis* / Q000453:epidemiology*; D000068476:Beijing / Q000453:epidemiology; D002648:Child; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D011594:Psychometrics; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires
keywords: CAST; China; autism; diagnosis; prevalence; screening