The Age at Diagnosis of Autism Spectrum Disorder in Children in Japan

Table 2

Basic attributes of the subjects .

Age at diagnosis in years
Modal age	3.0
Median (25th–75th percentile)	6.0 (4.0–10.0)
Mean ± SD	7.2 ± 4.2
Sex (%)
Male	6285 (76.1)
Female	1979 (23.9)
Autism spectrum disorder^†1   (%)
Childhood autism	2778 (33.6)
Atypical autism	241 (2.9)
Asperger’s syndrome	773 (9.4)
Other pervasive developmental disorder	56 (0.7)
Pervasive developmental disorder, unspecified	3931 (47.6)
Dual and multiple diagnosis	485 (5.9)
Medical facilities (%)
National hospital, public hospital	1989 (24.1)
University hospital	392 (4.7)
Other hospital	1509 (18.3)
Medical office	4374 (52.9)
Diagnosis and treatment department (%)
Paediatrics	2991 (36.2)
Neuropsychiatry	2368 (28.7)
Internal medicine	2025 (24.5)
Orthopedics	167 (2.0)
Obstetrics and gynecology	114 (1.4)
Otolaryngology	46 (0.6)
Radiology	44 (0.5)
Ophthalmology	38 (0.5)
Neurosurgery	22 (0.3)
Urology	17 (0.2)
Others	432 (5.2)

Subtype of PDD using the first date of diagnosis (exclusion of RS).