From: Prospective study of autism phenomenology and the behavioural phenotype of Phelan–McDermid syndrome: comparison to fragile X syndrome, Down syndrome and idiopathic autism spectrum disorder
Group
% scoring above ASD cutoff
(N)
% scoring above autism cutoff
PMS
86.7
(26)
56.7
(17)
FraX
80.0
(24)
51.9
(14)
DS
23.3
(7)
22.2
(6)
Idiopathic ASD
100.0
(30)
76.7
(23)