The Autism-Spectrum Quotient (AQ)—Adolescent Version

Abstract

The Autism Spectrum Quotient (AQ) quantifies autistic traits in adults. This paper adapted the AQ for children (age 9.8-15.4 years). Three groups of participants were assessed: Group 1: n=52 adolescents with Asperger Syndrome (AS) or high-functioning autism (HFA); Group 2: n=79 adolescents with classic autism; and Group 3, n=50 controls. The adolescents with AS/HFA did not differ significantly from the adolescents with autism but both clinical groups scored higher than controls. Approximately 90% of the adolescents with AS/HFA and autism scored 30+, vs. none of the controls. Among the controls, boys scored higher than girls. The AQ can rapidly quantify where an adolescent is situated on the continuum from autism to normality.

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The Autism-Spectrum Quotient (AQ)—Adolescent Version
Simon Baron-Cohen,
1,2
Rosa A. Hoekstra,
1
Rebecca Knickmeyer,
1
and Sally Wheelwright
1
The Autism Spectrum Quotient (AQ) quantifies autistic traits in adults. This paper adapted
the AQ for children (age 9.8–15.4 years). Three groups of participants were assessed: Group 1:
n=52 adolescents with Asperger Syndrome (AS) or high-functioning autism (HFA); Group 2:
n=79 adolescents with classic autism; and Group 3, n=50 controls. The adolescents with AS/
HFA did not differ significantly from the adolescents with autism but both clinical groups
scored higher than controls. Approximately 90% of the adolescents with AS/HFA and autism
scored 30+, vs. none of the controls. Among the controls, boys scored higher than girls. The
AQ can rapidly quantify where an adolescent is situated on the continuum from autism to
normality.
KEY WORDS: AQ; adolescents; screening; autistic spectrum; Asperger Syndrome.
INTRODUCTION
In an earlier issue in this journal, we reported
on the Autism Spectrum Quotient (AQ) in adults
with high functioning autism (HFA) or Asperger
Syndrome (AS) (Baron-Cohen, Wheelwright, Skin-
ner, Martin, & Clubley, 2001). The adult AQ was
developed because of a lack of a quick and quan-
titative self-report instrument for assessing how
many autistic traits any adult has. The minimum
score on the AQ is 0 and the maximum 50. If an
adult has equal to or more than 32 out of 50 such
traits, this is highly predictive of AS. The AQ has
been found to correlate inversely with the Empathy
Quotient (EQ) (Baron-Cohen & Wheelwright, 2004),
the Friendship and Relationship Quotient (FQ)
(Baron-Cohen & Wheelwright, 2003) and to corre-
late positively with the Systemizing Quotient (SQ)
(Baron-Cohen, Richler, Bisarya, Gurunathan, &
Wheelwright, 2003).
The AQ has also been found to be strongly
predictive of who receives a diagnosis of AS in a clinic
setting (Woodbury-Smith, Robinson, & Baron-Cohen,
2005). The AQ also reveals sex differences (males>
females) and cognitive differences (scientists>non-
scientists) (Baron-Cohen et al., 2001), a pattern of
results that has been closely replicated in a Japanese
sample (Wakabayashi, Baron-Cohen, & Wheelwright,
2004). This latter pattern suggests that these effects are
not culture-specific and may instead reflect sexual
dimorphism in the brain and differences in neural
organization between scientists (a clear example of
‘systemizersÕ) and non-scientists.
The AQ depends on self-report, which may be a
concern in individuals whose social deficits may
impair their accuracy in self-awareness. However, a
parent-version confirms that adults of normal IQ
with autism spectrum conditions are able to provide
such information reliably (Baron-Cohen et al., 2001).
Although the AQ is useful both clinically and in
research studies as a screen for diagnosis, it has not
been studied as a general population screen, and
indeed if it was tested for this purpose it is likely that
1
Department of Psychiatry, Autism Research Centre, University
of Cambridge, Cambridge, UK.
2
Correspondence should be addressed to: Simon Baron-Cohen,
Department of Psychiatry, Autism Research Centre, University
of Cambridge, Douglas House, 18b Trumpington Road, CB2
2AH, Cambridge, UK.; e-mail: sb205@cam.ac.uk
Journal of Autism and Developmental Disorders, Vol. 36, No. 3, April 2006 (Ó 2006)
DOI 10.1007/s10803-006-0073-6
Published Online: March 22, 2006
343
0162-3257/06/0400-0343/0 Ó 2006 Springer ScienceþBusiness Media, Inc.

a significantl y higher cut-off would need to be
employed to keep false-positives to a minimum.
Given the usefulness of the AQ, it is of interest to
test a revised version of this instrument with adoles-
cents. In this paper, we test (1) whether similar results
are found on an adolescent version of the AQ, and (2)
whether similar results are found in classic autism as in
AS. Whereas the ad ult AQ (for ages 16+) entails self-
report, the adolescent AQ requires a parent/carer to
complete it, but otherwise retains the same items and
structure as the adult version. The adolescent AQ was
designed to be short, easy to use, and easy to score.
The adolescent version is shown in Appendix 1.
It comprises 50 questions, made up of 10 questions
assessing 5 different areas: social skill (items
1,11,13,15,22,36,44,45,47,48); attention switching
(items 2,4,10,16,25,32,34,37,43,46); attention to detail
(items 5,6,9,12,19,23,28,29,30,49); communication
(items 7,17,18,26,27,31,33,35,38,39); and imagination
(items 3,8,14,20 ,21,24,40,41,42,50). Each of the items
listed above scores 1 point if the respondent records
the abnormal or autistic-like behaviour either
mildly or strongly (see below for scoring each item;
Abnormality—poor social skill, poor communication
skill, poor imagination, exceptional attention to
detail, poor attention-switching/strong focus of atten-
tion). Approximately half the items were worded to
produce a ‘disagreeÕ response, and half an ‘agreeÕ
response, in a high scoring person with AS/HFA.
This was to avoid a response bias either way.
Following this , items were randomized with respect
to both the expected response from a high-s corer, and
with respect to their domain.
Participants
3 groups of participants were tested:
Group 1 comprised n=52 adolescents with AS/
HFA (38 males, 14 females). This sex ratio of 2.7:1
(m:f) is similar to that found in other samples (Klin,
Volkmar, Sparrow, Cicchetti, & Rourke, 1995). All
participants in this group had been diagnosed by
psychiatrists using established criteria for autism or
AS (APA, 1994). They were recruited via several
sources, including the National Autistic Society (UK),
specialist clinics carrying out diagnostic assessments,
and adverts in newsletters/web-pages for children with
AS/HFA. Their mean age was 13.6 years (SD=2.0,
range 10.3–15.4). They all attended mains tream
schooling and by parental report, had an IQ in the
normal range. See below for a check of this. Because we
did not collect data on age of onset of language these
individuals are grouped together, rather than attempt-
ing to separate them into AS vs. HFA. The final sample
of 52 comprises those who responded from a larger
sample of 63. All participants were regarded as
independent, in being gen etically unrelated.
Group 2 comprised n=79 adolescents with clas-
sic autism (63 males, 16 females). Again, this sex ratio
of 3.9:1 is similar to that found in other samples. All
participants in this group had been diagnosed by
psychiatrists using established criteria for autism
(APA, 1994). They too were recruited via the
National Autistic Society (UK), specialist clinics
carrying out diagnostic assessments, and adverts in
newsletters/web-pages for children with autism. Their
mean age was 12.5 years (SD=1.7, range 9.8–16.0).
They all attended special schools for autism or
learning difficulties, and by parental report, had an
IQ below the normal range. See below for a check of
this. The final sample of 79 comprised those who
responded from a larger sample of 85.
Group 3 comprised 50 adolescents selected at
random (n=25 males and 25 females). They were
drawn from 200 adolescents. They were all attending
mainstream schools (2 primary and 2 secondary) in
the East Anglia area. Questionnaires were distributed
by the schoolteachers via the childrenÕs school class.
Their mean age was 13.6 years (SD=1.8, range 10.1--
16.5). The 3 groups did not differ significantly at the
p=.05 level for age.
In Groups 1 and 2, 15 individuals were randomly
selected from the individuals who had returned an
AQ and invited into the lab to check pro-rated IQ,
using 4 subtests of the WAIS-R (see below). These
parents were also asked to complete a second AQ as a
measure of test–retest reliabil ity.
Method
Parents were sent the AQ by post, and were
instructed to complete it as quickly as possible (to
avoid thinking about responses too long). To confirm
the diagnosis of Group 1 being high-functioning and
the diagnosis of Group 2 being lower-functioning, 15
of each were randomly selected and invited into the
lab for intellectual assessment using 4 subtests of
the WISC-R (Wechsler, 1958). The 4 subtests of the
WISC-R were Vocabulary, Similarities, Block
Design, and Picture Completion. On this basis, all
15 participants selected from Group 1 had a prorated
IQ of at least 85, that is, in the normal range
(mean=106.5, SD=8.0). These participantsÕ parents
were also given the AQ when they came into the lab
344 Baron-Cohen, Hoekstra, Knickmeyer, and Wheelwright

in person, in order to investigate test–retest reliability
for the instrument on a small subset of children. All
15 of the participants selected from Group 2 had a
prorated IQ of below 84, that is, below the normal
range (mean=72.6, SD=8.0). Note that we have
conservatively used an IQ of >85 as an inclus ion
criterion for AS/HFA.
Scoring the AQ
‘Definitely agreeÕ or ‘slightly agreeÕ responses
scored 1 point, on the following items: 2, 4, 5, 6, 7, 9,
12, 13, 16, 18, 19, 20, 21, 22, 23, 26, 33, 35, 39, 41, 42,
43, 45, 46. ‘Definitely disagreeÕ or ‘slightly disagreeÕ
responses scored 1 point, on the following items: 1, 3,
8, 10, 11, 14, 15 , 17, 24, 25, 27, 28, 29, 30, 31, 32, 34,
36, 37, 38, 40, 44, 47, 48, 49, 50. If a respond ent left
more than 5 items blank, this AQ was deemed to be
incomplete and was omitted from the sample.
Results
Mean AQ scores (total) for each group, broken
down by sex and by subdomain, are shown in
Table I. Comparing groups using an ANOVA of
Total AQ score by GROUP and SEX, we found as
predicted a significant effect of GROUP (F (2,
175)=201.49, p<.001). Post Hoc Scheffe tests
revealed that the two clinical groups scored signif-
icantly higher than the control group (p<.0001), but
that the two clinical groups did not differ from each
other. The main effect of SEX was not signi ficant (F
(1, 175)=2.84, p>.09), but there was a significant
two-way interaction of GROUPSEX (F (2,
175)=6.48, p=.002).
T-tests confirmed that there was a significant sex
difference (t=)3.27, p=.002) in the control group
(males scoring higher than females), confirming the
same effect reported with the adult AQ. There were
no significant sex differences in the clinical groups
(group 1: t=1.90, p =.063; group 2: t=)2.0, p=.049
(non-significant when Bonferroni correction for
multiple tests is used)). The clinical groups differed
from the control group on all subdomain scores (t-
tests: see Table I). A stepwise regression analysis in
the control group revealed a significant effect of sex
(F (1, 191)=23.24, p<.001, males scoring higher),
but no effect of age (t=)1.45, p=.149). Figure 1
shows the Group and Sex differences graphically.
Table I. Mean AQ and Subscale Scores (and SDs) by Group
Communication Social Imagination Local details Attention switching Total AQ
Group 1
AS/HFA (n=52) x 8.2 7.8 6.7 6.1 8.5 37.3
SD 1.6 1.8 2.2 2.4 1.7 5.8
AS/HFA boys (n=38) x 7.9 7.4 6.8 6.1 8.2 36.4
SD 1.6 1.7 2.3 2.5 1.9 6.0
AS/HFA girls (n=14) x 9.0 8.8 6.8 6.1 9.0 39.8
SD 1.4 1.4 2.0 2.4 1.0 4.3
Group 2
Autism (n=79) x 8.0 8.0 7.6 6.5 8.3 38.3
SD 1.5 1.9 2.0 2.1 1.6 6.0
Autism boys (n=63) x 8.1 8.2 7.7 6.6 8.3 39.0
SD 1.5 1.8 2.0 2.2 1.6 5.9
Autism girls (n=16) x 7.6 7.3 6.8 5.9 8.1 35.7
SD 1.6 2.0 2.1 1.9 1.8 6.1
Group 3
Controls (n=50) x 2.7 2.0 3.2 5.3 4.5 17.7
SD 1.7 1.9 2.3 2.4 2.0 5.7
Control boys (n=25) x 2.9 2.2 4.4 5.8 5.0 20.2
SD 1.8 1.9 2.2 2.6 1.7 4.8
Control girls (n=25) x 2.6 1.8 2.0 4.8 4.1 15.3
SD 1.6 1.9 1.8 2.2 2.1 5.7
Controls vs. AS/HFA t
a
)16.9 )15.7 )7.9 )1.7
#
)10.7 )17.2
Controls vs. autism t
a
)18.4 )17.7 )11.2 )2.8 )11.2 )19.2
AS/HFA vs. autism T
b
0.7 )0.8 )2.0 )0.8 )0.7 )0.9
a
All t values in this row are significant at the p<.001 level except where shown (
#
).
b
None of these t values are significant at the p<.05 level.
Adolescent AQ 345

An item analysis (percentage of each group
scoring on each item) is shown in Table II. On only 2
items out of 50 (items 29, and 30) did controls score
more than the clinical groups, strongly confirming the
value of these items for discriminating autism spec-
trum vs. controls. These two items were conserva-
tively retain ed in the analysis since, if anything, they
served to reduce the size of group differences. The
internal consistency of items in each of the 5 domains
was also calculated, and CronbachÕs a Coefficients
were all high (Communication=0.82; Social=0.88;
Imagination=0.81; Attention to Detail=0.66; Atten-
tion Switching=0.76). CronbachÕs a Coefficient for
the AQ as a whole was also high (=0.79). CronbachÕs
a Coefficients for each group were all in the range
0.6–0.9.
The pe rcentage of each group scoring at or
above each AQ score is shown in Table III. A useful
cut-off would discriminate the groups with as many
true positives and as few false positives as possible. In
the adults AQ, an AQ score of 32+ was chosen as a
useful cut-off, since 79.3% of the AS/HFA group
scored at this level, whilst only 2% of controls did so.
32+ also seemed to be a useful cut-off for distin-
guishing adult females with AS/HFA (92.3% scoring
at this point or above) vs. control adult females (1%
of whom score at this point or above). Regar ding the
adolescent AQ, if the same cut-off score is used (of
32+), none of the control participants scored at this
level, whilst all girls with AS/HFA scored above this
level, as do 73.7% of the boys with AS/HFA. In the
autism group, 68.8% of the girls, and 87.3% of the
boys scored at this level. If we decrease the cut-off
score to 30+, none of the controls score above this
level. All AS/HFA girls, and 86.8% of the AS/HFA
boys score abo ve this level, compared to 81.3% (girls)
and 90.5% (boys) in the autism group. A cut-off at
this point might be consider ed in future screening
studies.
Table III also shows that control females never
score as high as 29+, whereas 4% of control males
do. Note also that at AQ score 22+, there are almost
four times as many males (44%) as females (12%)in
the control group scoring at this intermediate point
on the scale. This suggests that there is not only a sex
difference on the child AQ overall (as reflected in the
male mean AQ being higher than the female mean),
and a sex difference at high levels on the AQ (reflected
in the sex ratio in Group 1 being 3.5:1), but that
significantly more males than females in the general
population show moderate levels of ‘‘autistic traits’’.
1
Again, this pattern of results replicates that found
with the adult AQ. No differences were found
between the autism and HFA/AS groups on the
AQ. Finally, test–retest reliability was high (r=.92,
p<.001).
0
5
10
15
20
25
30
35
40
0 to 5
6 to 10
11 to 15
16 to 20
21 to 25
26 to 30
31 to 35
36 to 40
41 to 45
46 to 50
AQ score
Percent of subjects
Control girls
Control boys
AS/HFA/Aut boys and girls
Fig. 1. Percent of each group scoring at each group score.
346 Baron-Cohen, Hoekstra, Knickmeyer, and Wheelwright

DISCUSSION
In this paper, we report data from the adolescent
version of the Autism Spectrum Quotient (AQ), for
measuring the degree to which an individual adoles-
cent shows autistic traits. As pr edicted, adolescents
with Asper ger Syndrome (AS)/high functioning aut-
ism (HFA) or with classic autism scored significantly
higher on the AQ than matched controls. Eighty
percent to 90% (mean=89.3%) scored above a critical
minimum of 30+, whereas none of the controls did
so. This demonstrates that the ado lescent AQ has
reasonable face validity, since the questionnaire pur-
ports to measure autistic spectrum traits, and people
with a diagnosis involving these traits score highly on
it. The adolescent AQ can also be said to have
reasonable construct validity, in that items purporting
to measure each of the 5 domains of interest (social,
communication, imagination, attention to detail, and
attention switching) show high a coefficients. Future
work needs to test the false negative rate. The
adolescent AQ has excellent test–retest reliability.
It is of interest that there were no significant
effects of age on adolescent AQ score, in the normal
control group. This suggests that what is being
measured by the AQ does not change with age, and
that the items are not biased towards one particular
age group. Regarding the comparison of classic
autism vs. HFA/AS, no significant differences were
found, which is also interesting. This may be because
the items are not biased towards language skills.
However, because of the communication subscale,
which includes items about conversational compe-
tence, we recommend that the AQ is primarily of
value for use with individuals with some speech, and
with an intelligence in the borderline average range
(70) or above.
Within the control group, males score slightly
but significantly higher than females, both overall,
and at intermediate and high levels of autistic traits.
This is consistent with the extreme male brain theory
of autism (Asperger, 1944; Baron-Cohen, 2002;
Baron-Cohen & Hammer, 1997) an d may have
implications for the marked sex ratio in autism and
AS (Wing, 1981).
It is important to mention that this study was
not in a position to compare the adolescent AQ to
other instruments that have been developed to
measure AS, such as the ASSQ (Ehlers, Gillberg, &
Wing, 1999), the CAST (Scott, Baron-Cohen, Bol-
ton, & Brayne, 2002), or the Australian Scale for
Asperger Syndrome (Attwood, 1997). It will be of
Table II. Item Analysis: Percentage of Each Group Scoring on
Each Item
ItemAS/HFA (n=52)Autism (n=79)Controls (n=50)Subdomain
1 67.3 83.5 22.0 S
2 84.6 89.9 54.0 A
3 55.8 70.3 18.0 I
4 90.4 94.9 68.0 A
5 80.8 87.3 50.0 D
6 65.4 72.2 68.0 D
7 78.8 54.4 28.0 C
8 56.9 75.0 20.0 I
9 40.4 39.7 26.0 D
10 86.3 92.4 26.0 A
11 86.5 88.6 26.0 S
12 92.3 85.9 62.0 D
13 55.8 55.7 8.0 S
14 59.6 84.8 34.0 I
15 90.4 88.6 26.5 S
16 88.5 91.1 62.0 A
17 88.5 92.4 8.0 C
18 73.1 39.7 48.0 C
19 45.1 45.6 34.0 D
20 75.0 78.7 34.0 I
21 51.9 60.3 42.0 I
22 92.3 89.9 20.0 S
23 63.5 72.2 40.0 D
24 63.5 64.5 48.0 I
25 82.7 81.0 32.0 A
26 92.3 89.9 24.0 C
27 86.5 96.2 42.0 C
28 78.8 84.4 36.0 D
29 51.9 48.1 76.0 D
30 51.9 66.7 76.0 D
31 82.7 92.4 28.0 C
32 86.5 93.7 42.0 A
33 75.0 80.8 10.0 C
34 78.8 74.7 16.0 A
35 71.2 88.6 26.0 C
36 90.4 70.9 14.3 S
37 80.8 57.0 26.0 A
38 84.6 97.5 10.0 C
39 88.5 73.1 48.0 C
40 88.2 96.2 24.0 I
41 69.2 58.2 28.0 I
42 82.7 94.8 38.0 I
43 75.0 65.8 62.0 A
44 50.0 65.8 12.0 S
45 94.2 93.7 44.0 S
46 94.2 86.1 66.0 A
47 63.5 74.7 14.0 S
48 84.6 91.1 12.0 S
49 44.2 49.4 62.0 D
50 78.8 89.9 34.0 I
Key: S, Social skills; A, Attention switching; D, Attention to detail;
C, Communication; I, Imagination.
Adolescent AQ 347

interest in future studies to test how many cases of
AS each of these instruments correctly identifies (true
positive rate) as well as the rate of false negatives.
Future work could also examine any relationship
between adolesc ent AQ score and severity of
symptoms.
We wish to underline that the AQ is not
diagnostic, but may serve as a useful instrument in
Table III. Percent of Participants in Groups 1 and 2 Scoring at or Above each AQ Score—Overleaf
AQ
Score
AS/HFA
(n=52)
AS boys
(n=38)
AS/HFA
girls (n=14)
Autism
(n=79)
Autism boys
(n=63)
Autism girls
(n=16)
Controls
(n=50)
Control
boys (n=25)
Control
girls(n=25)
0 100 100 100 100 100 100 100 100 100
1 100 100 100 100 100 100 100 100 100
2 100 100 100 100 100 100 100 100 100
3 100 100 100 100 100 100 100 100 100
4 100 100 100 100 100 100 100 100 100
5 100 100 100 100 100 100 98.0 100 96.0
6 100 100 100 100 100 100 98.0 100 96.0
7 100 100 100 100 100 100 98.0 100 96.0
8 100 100 100 100 100 100 98.0 100 96.0
9 100 100 100 100 100 100 92.0 100 84.0
10 100 100 100 100 100 100 90.0 100 80.0
11 100 100 100 100 100 100 88.0 100 76.0
12 100 100 100 100 100 100 84.0 100 68.0
13 100 100 100 100 100 100 80.0 96.0 64.0
14 100 100 100 100 100 100 74.0 88.0 60.0
15 100 100 100 100 100 100 72.0 88.0 56.0
16 100 100 100 100 100 100 70.0 84.0 56.0
17 100 100 100 100 100 100 60.0 72.0 48.0
18 100 100 100 100 100 100 52.0 64.0 40.0
19 100 100 100 100 100 100 48.0 60.0 36.0
20 100 100 100 100 100 100 44.0 56.0 32.0
21 100 100 100 100 100 100 34.0 48.0 20.0
22 100 100 100 100 100 100 28.0 44.0 12.0
23 100 100 100 100 100 100 22.0 36.0 8.0
24 98.1 97.4 100 100 100 100 14.0 24.0 4.0
25 98.1 97.4 100 98.7 100 93.8 14.0 24.0 4.0
26 98.1 97.4 100 98.7 100 93.8 6.0 12.0 0
27 98.1 97.4 100 96.2 96.8 93.8 4.0 8.0 0
28 94.2 92.1 100 93.7 95.2 87.5 4.0 8.0 0
29 92.3 89.5 100 92.4 93.7 87.5 2.0 4.0 0
30 90.4 86.8 100 88.6 90.5 81.3 0 0 0
31 88.5 84.2 100 87.3 90.5 75.0 0 0 0
32 80.8 73.7 100 83.5 87.3 68.8 0 0 0
33 76.9 68.4 100 83.5 87.3 68.8 0 0 0
34 71.2 65.8 85.7 75.9 77.8 68.8 0 0 0
35 65.4 60.5 78.6 73.4 74.6 68.8 0 0 0
36 63.5 57.9 78.6 68.4 71.4 56.3 0 0 0
37 59.6 52.6 78.6 64.6 69.8 43.8 0 0 0
38 57.7 52.6 71.4 60.8 66.7 37.5 0 0 0
39 46.2 39.5 64.3 53.2 57.1 37.5 0 0 0
40 38.5 31.6 57.1 49.4 54.0 31.3 0 0 0
41 32.7 26.3 50.0 43.0 46.0 31.3 0 0 0
42 30.8 26.3 42.9 38.0 41.3 25.0 0 0 0
43 21.2 18.4 28.6 30.4 34.9 12.5 0 0 0
44 17.3 15.8 21.4 19.0 22.2 6.3 0 0 0
45 9.6 7.9 14.3 13.9 17.5 0 0 0 0
46 3.8 2.6 7.1 10.1 12.7 0 0 0 0
47 1.9 2.6 0 5.1 6.3 0 0 0 0
48 0 0 0 3.8 4.8 0 0 0 0
49 0 0 0 2.5 3.2 0 0 0 0
50 0 0 0 0 0 0 0 0 0
348 Baron-Cohen, Hoekstra, Knickmeyer, and Wheelwright

identifying the extent of autistic traits shown by a
person of normal intelligence. Currently this woul d
be for research purposes primarily, as the AQ has
not been tested as a screening instrument in the
general population. Fut ure research could compare
the sensitivity, specificity, and positive predictive
value (PPV) of this instrument in community
screening. Finally, the hope is that with quantitative
instruments to measure the autistic spectrum across
different ages, this will improve comparability across
research studies, assist in defining the phenotype in
genetic studies, and improve screening of undiag-
nosed cases who need to be referred for a full
diagnostic assessment.
NOTE
1. i.e. those traits which people with AS or HFA
tend to endorse on the AQ.
ACKNOWLEDGMENTS
The authors were supported by a grant from the
MRC and the Lurie-Marks Foundation, during the
period of this work. Rosa Hoekstra was supported by
a grant from the HsN Hersenstichting Nederland,
the Bekker-La Bastide Fund and the Schuurman
Schimmel van Outeren Foundation.
APPENDIX 1: The Adolescent AQ
Definitely
agree
Slightly
agree
Slightly
disagree
Definitely
disagree
1. S/he prefers to do things with others rather than on her/his own.
2. S/he prefers to do things the same way over and over again.
3. If s/he tries to imagine something, s/he finds it very easy to create a picture in her/his mind.
4. S/he frequently gets so strongly absorbed in one thing that s/he loses sight of other things.
5. S/he often notices small sounds when others do not.
6. S/he usually notices car number plates or similar strings of information.
7. Other people frequently tell her/him that what s/he has said is impolite, even though s/he thinks
it is polite.
8. When s/he is reading a story, s/he can easily imagine what the characters might look like.
9. S/he is fascinated by dates.
10. In a social group, s/he can easily keep track of several different people’s conversations.
11. S/he finds social situations easy.
12. S/he tends to notice details that others do not.
13. S/he would rather go to a library than a party.
14. S/he finds making up stories easy.
15. S/he finds her/himself drawn more strongly to people than to things.
16. S/he tends to have very strong interests, which s/he gets upset about if s/he can’t pursue.
17. S/he enjoys social chit-chat.
18. When s/he talks, it isn’t always easy for others to get a word in edgeways.
19. S/he is fascinated by numbers.
20. When s/he is reading a story, s/he finds it difficult to work out the characters’ intentions.
21. S/he doesn’t particularly enjoy reading fiction.
22. S/he finds it hard to make new friends.
23. S/he notices patterns in things all the time.
24. S/he would rather go to the theatre than a museum.
25. It does not upset him/her if his/her daily routine is disturbed.
26. S/he frequently finds that s/he doesn’t know how to keep a conversation going.
27. S/he finds it easy to ‘‘read between the lines’’ when someone is talking to her/him.
28. S/he usually concentrates more on the whole picture, rather than the small details.
29. S/he is not very good at remembering phone numbers.
30. S/he doesn’t usually notice small changes in a situation, or a person’s appearance.
31. S/he knows how to tell if someone listening to him/her is getting bored.
32. S/he finds it easy to do more than one thing at once.
33. When s/he talks on the phone, s/he is not sure when it’s her/his turn to speak.
34. S/he enjoys doing things spontaneously.
35. S/he is often the last to understand the point of a joke.
36. S/he finds it easy to work out what someone is thinking or feeling just by looking at their face.
Adolescent AQ 349

REFERENCES
APA. (1994). DSM-IV diagnostic and statistical manual of mental
disorders, 4th ed. Washington DC: American Psychiatric
Association.
Asperger, H. (1944). Die ‘‘Autistischen Psychopathen’’ im
Kindesalter. Archiv fur Psychiatrie und Nervenkrankheiten,
117, 76–136.
Attwood, T. (1997). AspergerÕs Syndrome. UK: Jessica Kingsley.
Baron-Cohen, S. (2002). The extreme male brain theory of autism.
Trends in Cognitive Sciences, 6, 248–254.
Baron-Cohen, S., & Hammer, J. (1997). Is autism an extreme form
of the male brain?. Advances in Infancy Research, 11, 193–217.
Baron-Cohen, S., Richler, J., Bisarya, D., Gurunathan, N., &
Wheelwright, S. (2003). The Systemising Quotient (SQ): An
investigation of adults with Asperger Syndrome or high
functioning autism and normal sex differences. Philosophical
Transactions of the Royal Society, Series B, Special issue on
‘‘Autism: Mind and Brain’’, 358, 361–374.
Baron-Cohen, S., & Wheelwright, S. (2003). The Friendship
Questionnaire (FQ): An investigation of adults with Asperger
Syndrome or high functioning autism, and normal sex differ-
ences. Journal of Autism and Developmental Disorders, 33, 509–
517.
Baron-Cohen, S., & Wheelwright, S. (2004). The Empathy Quo-
tient (EQ). An investigation of adults with Asperger Syndrome
or high functioning autism, and normal sex differences. Jour-
nal of Autism and Developmental Disorders, 34, 163–175.
Baron-Cohen, S., Wheelwright, S., Skinner, R., Martin, J., &
Clubley, E. (2001). The Autism Spectrum Quotient (AQ):
Evidence from Asperger Syndrome/high functioning autism,
males and females, scientists and mathematicians. Journal of
Autism and Developmental Disorders, 31, 5–17.
Ehlers, S., Gillberg, C., & Wing, L. (1999). A screening question-
naire for Asperger Syndrome and other high-functioning
autism spectrum disorders in school-age children. Journal of
Autism and Developmental Disorders, 29, 129–141.
Klin, A., Volkmar, F., Sparrow, S., Cicchetti, D., & Rourke, B.
(1995). Validity and neuropsychological characterization of
Asperger Syndrome: Convergence with nonverbal learning
disabilities syndrome. Journal of Child Psychology and Psy-
chiatry, 36, 1127–1140.
Scott, F., Baron-Cohen, S., Bolton, P., & Brayne, C. (2002). The
CAST (Childhood Asperger Syndrome Test): Preliminary
development of UK screen for mainstream primary-school
children. Autism, 6(1), 9–31.
Wakabayashi, A., Baron-Cohen, S., & Wheelwright, S. (2004). The
Autism-Spectrum Quotient (AQ) Japanese version: Evidence
from high-functioning clinical group and normal adults. The
Japanese Journal of Psychology, 75, 78–84.
Wechsler, D. (1958). Sex differences in intelligence : The measure-
ment and appraisal of adult intelligence. Baltimore: Williams &
Wilking.
Wing, L. (1981). Asperger Syndrome: A clinical account. Psycho-
logical Medicine, 11, 115–130.
Woodbury-Smith, M., Robinson, J., & Baron-Cohen, S. (2005).
Screening adults for Asperger Syndrome using the AQ: diag-
nostic validity in clinical practice. Journal of Autism and
Developmental Disorders, 35, 331–335.
Appendix 1. (Continued)
Definitely
agree
Slightly
agree
Slightly
disagree
Definitely
disagree
37. If there is an interruption, s/he can switch back to what s/he was doing very quickly.
38. S/he is good at social chit-chat.
39. People often tell her/him that s/he keeps going on and on about the same thing.
40. When s/he was younger, s/he used to enjoy playing games involving pretending with other
children.
41. S/he likes to collect information about categories of things (e.g. types of car, types of bird, types
of train, types of plant, etc.).
42. S/he finds it difficult to imagine what it would be like to be someone else.
43. S/he likes to plan any activities s/he participates in carefully.
44. S/he enjoys social occasions.
45. S/he finds it difficult to work out people’s intentions.
46. New situations make him/her anxious.
47. S/he enjoys meeting new people.
48. S/he is a good diplomat.
49. S/he is not very good at remembering people’s date of birth.
50. S/he finds it very to easy to play games with children that involve pretending.
Ó MRC-SBC/SJW Feb 1998.
350 Baron-Cohen, Hoekstra, Knickmeyer, and Wheelwright