Rowland D (2020) Differential Diagnosis of Autism: A Causal Analysis. J Neurol Neurophysiol 11: 489
There are three appendices to this article that you may wish to view at: https://www.omicsonline.org/open-access/differential-diagnosis-of-autism-a-causal-analysis.pdf
A diagnosis without knowing the cause is merely a label that creates the illusion of understanding. Autism is over-diagnosed and now includes a spectrum of conditions of uncertain similarity, primarily because professionals are diagnosing by ticking off symptoms on a checklist with minimal understanding of cause and effect. This study (a) identifies the unique and defining characteristic of autism that is responsible for all its observed traits, (b) maps the neurophysiological differences between an autistic and a neurotypical brain, (c) explains the neuropsychological differences between autism and conditions that are often mistaken for it, and (d) provides a litmus test whereby you can know for certain if someone suspected of being autistic has been correctly diagnosed.