Project description

Autism is now identified as a spectrum of varying severity, autism spectrum disorder (ASD). This diagnosis is obtained by exceeding a threshold of signs defined by abstract descriptions (e.g., "stereotyped and repetitive movements"). The imprecision of each sign adds up to a loosely defined category, the autistic "spectrum", which allows and encourages a steady increase in reported prevalence and heterogeneity. Indeed, the overall prevalence of ASD reached 0.82% in 2016 among the 1-5 year-old population in Quebec (Early Childhood Observatory, 2016). To limit this imprecision, we propose to reconceptualize autistic signs based on the objective and universal recognition of their qualitative aspects. We will create a video atlas of signs that together constitute the "prototypical" ASD. A series of signs from a clinically established list will be sought in a corpus of diagnostic video recordings (ADOS) of children clinically representative of autism. An initial sample of videos of varying quality and representativeness will be established by inter-rater agreement. This sample will be presented to 16 clinicians, experts in the diagnosis of autism in preschool-aged children, so that they in turn can classify the videos according to their representativeness, based on their experience. The ranking of videos will be compared by quantile tests between experts to identify the most prototypical videos. Objectivizing the clinical judgment for each sign will make it possible, by bringing them together, to identify a category of individuals within the autism spectrum who are highly similar to one another. What's more, a visual catalog of the prototypical qualitative signs of ASD would provide a common basis for all experts and future experts, from which to recast the limits of the spectrum's heterogeneity.