Table 2.

Summary of studies published since 2000 examining the prevalence of epileptiform EEGs in ASD populations (total samples and special populations within sample such as those without epilepsy).

Sample size	Age	Ascertainment	Diagnosis	Type of EEG	Epileptiform EEG Rate	Reference
60	Mean 3.11 yrs. Range 2- 6 yrs.	Clinic Based	PDD-NOS, Autism	Routine	30% w/out epilepsy	(36)
64	Mean 36 mo. Range 18-48 mo.	Clinic Based	Autism	Sleep	31% w/out epilepsy	(37)
46	Mean 7.8 yrs.	Clinic Based	Autism, PDD	Awake & Sleep	35% overall 22% w/out epilepsy	(28)
889	Mean 5.3 yrs.	Clinic Based	ASD	24-Hr EEG	60.7% w/out epilepsy	(13)
56	Range 1-14 yrs.	Clinic Based	Autism (n=35), PDD- NOS (n=18), or Aspergers (n=3)	Awake & Sleep	30% overall 3.6% w/out epilepsy Autism Group: 5.7% w/out Epilepsy	(38)
104	Range 30mo.-8 yrs.	Clinic Based	Autism or ASD	Awake & Sleep	40.5% overall	(33)
60	Mean 17.6 yrs. Range 12-29.9 yrs.	Clinic Based	Autism	Awake & Sleep	6.7% w/out epilepsy	(30)
130	Range 18-35 yrs.	Clinic Based	Autism and Atypical	Routine	21% w/out epilepsy	(11)
77	Mean 9.1 yrs.	Clinic Based	PDD, Autism, Atypical Autism, CDD, Aspergers	Awake & Sleep	38% overall 30% w/out epilepsy	(21)
59	Range 0.5-21 yrs.	Clinic Based	Autism	Awake & Sleep	75% overall	(6)
32	Mean 5 yrs.	Clinic Based	Autism	Prolonged Video- EEG	59% w/out epilepsy	(14)
77	Mean 17.08 yrs.	Clinic Based	PDD-NOS & AUTISM	Awake & Sleep	45.5% Autism overall 62.3 % PDD overall 17.4% PDD w/out epilepsy	(12)