According to the Institut National de la Santé et de la Recherche Médicale (National Institute for Health and Medical Research), or Inserm for short, autism is a pervasive developmental disorder (PDD) which refers to a group of disorders characterised by delays in the development of multiple basic functions including socialisation, communication (both verbal and non-verbal).  This includes behavioural problems related to a range of interests and restricted activities, standardised and repetitive.

The disability associated with autism varies, ranging from mild to severe. It is almost always associated with learning difficulties.

Autism appears in early childhood, before the age of 3, and persists throughout life.

An estimated 100,000 children under the age of 20 have a PDD in France. Childhood autism affecting about 30,000 of them (*).

Three million people have this disorder in the United States. Tens of millions are affected in the world (**).

One child in 100 is said to be suffering from some form of autism worldwide. For reasons as yet undetermined, boys are four times more likely than girls to suffer from this disorder (***).

(*) : http://www.inserm.fr/thematiques/neurosciences-sciences-cognitives-neurologie-psychiatrie/dossiers-d-information/autisme
(**) : https://www.autismspeaks.org/what-autism
(***) : https://www.pasteur.fr/fr/institut-pasteur/presse/fiches-info/autisme