Table 1.

Participant Age, IQ, and Diagnostic Measures

Variable	Control Group	Autism Group
Study 1
No. of subjects	12	12
Age, y
Range	13-23	10-24
Mean ± SD	17.0 ± 2.9	16.8 ± 4.5
ADI-R score*
QIRS	NA	25.4 ± 3.0
NVC	NA	11.6 ± 2.1
VC	NA	17.9 ± 2.7
RB	NA	4.6 ± 3.0
Study 2
No. of subjects	14	16†
Age, y
Range	8-21	8-25
Mean ± SD	13.7 ± 3.9	14.3 ± 4.7
IQ*
Full scale	122 ± 13	97 ± 26‡
Verbal	119 ± 14	91 ± 27‡
Performance	122 ± 13	102 ± 12‡
ADI-R score*
QIRS	NA	20.7 ± 7.4§
NVC	NA	8.6 ± 3.5∥
VC	NA	14.5 ± 4.5
RB	NA	6.6 ± 2.7

Abbreviations: ADI-R, Autism Diagnostic Interview–Revised; NA, data not applicable; NVC, nonverbal communication; QIRS, qualitative impairment in reciprocal social behavior; RB, repetitive behavior; VC, verbal communication;

^*Data are given as mean ± SD.

^†Five of these subjects had Asperger syndrome or pervasive developmental disorder not otherwise specified.

^‡Significantly different (P<.01 for all) from the control group.

^§There was a trend toward lower scores than in study 1 (P=.06).

^∥Significantly different (P=.02) from study 1.