Prevalence of autism spectrum disorder and autistic symptoms in a school‐based cohort of children in Kolkata, India

Abstract

Despite housing ∼18% of the world's population, India does not yet have an estimate of prevalence of autism. This study was carried out to estimate the prevalence of autism in a selected population of school‐children in India. N = 11,849 children (mean age = 5.9 [SD = 1.3], 39.5% females) were selected from various school types from three boroughs in Kolkata, India. Parents/caregivers and teachers filled in the social and communication disorders checklist (SCDC). Children meeting cutoff on parent‐reported SCDC were followed up with the social communication questionnaire (SCQ). SCQ‐positive children were administered the autism diagnostic observation schedule (ADOS). Teacher report on SCDC was available on all 11,849 children. Parent‐report SCDC scores were obtained for 5,947 children. Mean scores on teacher SCDC were significantly lower than parent SCDC. Out of 1,247 SCDC‐positive children, 882 answered the SCQ, of whom 124 met the cutoff score of 15. Six of these children met criteria for autism, autism spectrum disorder (ASD), or broader autism spectrum on the ADOS. The weighted estimate of supra‐threshold SCQ scores was 3.54% (CI: 2.88–4.3%). The weighted prevalence estimate of positive scores (for broader autism spectrum + ASD + autism) was 0.23% (0.07–0.46%). As ∼20% children in this state are known to be out of the school system, and ASD prevalence is likely to be higher in this group, this estimate is likely to represent the lower‐bound of the true prevalence. This study provides preliminary data on the prevalence of broader‐spectrum autism and supra‐threshold autistic traits in a population sample of school children in Eastern India. Autism Res 2017, 10: 1597–1605. ©2017 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research

Exploring diagnostic validity of the autism diagnostic observation schedule‐2 in South Korean toddlers and preschoolers

“…Given the increased awareness of the importance of early diagnosis and intervention for children with autism spectrum disorders (ASD), gold standard diagnostic measures, such as the Autism Diagnostic Observation Schedule [Lord et al, ] and Autism Diagnostic Observation Schedule‐2 (ADOS‐2 [Lord et al, ]), have become more accessible internationally for young children with ASD [Baird et al, ; Baron‐Cohen et al, ; Boilson, Staines, Ramirez, Posada, & Sweeney, ; Fombonne et al, ; Kim et al, ; Morales‐Hidalgo, Roigé‐Castellví, Hernández‐Martínez, Voltas, & Canals, ; Rudra et al, ; Sun, Allison, Matthews, et al, ]. The increased use of the ADOS‐G/ADOS‐2 in international studies has also been driven by the translation of the ADOS‐G/ADOS‐2 into more than 12 languages; however, studies examining the diagnostic validity of the measure have been mainly conducted in Western countries including the United States [Gotham, Risi, Pickles, & Lord, ], Canada [Risi et al, ], United Kingdom [Le Couteur, Haden, Hammal, & McConachie, ], the Netherlands [de Bildt et al, ], Germany [Bölte & Poustka, ], Poland [Chojnicka & Pisula, ], Greece [Papanikolaou et al, 2009], and Sweden [Zander, Sturm, & Bölte, ].…”

The Caregiver Reported Autistic Symptoms in Preschool Children: Findings of Chandigarh Autism Screening Instrument (CASI) Linked Screening from North India

“…The Hindi version of SCDC is identified as a valid tool and a cutoff score of 9 was used for measuring autistic symptoms in a previous school-based study conducted in the Indian setting. 11 The modified Kuppuswamy scale was used for assessing the socioeconomic status of the caregivers.…”

Chronic Fluoride Exposure and the Risk of Autism Spectrum Disorder

“…The last available study reports the prevalence of ASD in South Asia ranging from 0.09% in India to 1.07% in Sri Lanka [88]. Preliminary data on the prevalence ASD in a population sample of school children in Eastern India [89] estimate 0.23% (0.07%–0.46%).…”