title: Differential diagnosis of the Williams and the Noonan syndromes.
abstract: A diagnostic index has been devised to distinguish between the Noonan and the Williams syndromes. Twins from the literature reported as having the Williams syndrome more likely represent the Noonan syndrome.
mesh_terms: D000293:Adolescent; D000886:Anthropometry; D002648:Child; D003937:Diagnosis, Differential; D006330:Heart Defects, Congenital / Q000175:diagnosis*; D006801:Humans; D008607:Intellectual Disability / Q000175:diagnosis*; D008297:Male; D009634:Noonan Syndrome / Q000175:diagnosis*; D010641:Phenotype; D013577:Syndrome; D009626:Terminology as Topic