Open Journal of Psychiatry, 2011, 1, 79-87
doi:10.4236/jsemat.2011.13012 Published Online October 2011 (http://www.SciRP.org/journal/OJPsych/
OJPsych
).
Published Online October 2011 in SciRes. http://www.scirp.org/journal/OJPsych
Extended time improves reading comprehension test scores
for adolescents with ADHD
Thomas Edwards Brown*, Philipp Christian Reichel, Donald Michael Quinlan
Department of Psychiatry, Yale University School of Medicine, New Haven, USA.
Received 29 August 2011; revised 20 September 2011; accepted 15 October 2011.
ABSTRACT
Objective: To test the hypotheses that reading com-
prehension difficulties of adolescent students with
ADHD: 1) are related not so much to weak verbal
abilities or weak basic reading skills, as to impair-
ments of working memory and processing speed
characteristic of ADHD; and 2) that extended time on
a test of reading comprehension would yield signifi-
cantly higher reading comprehension scores than
would standard time. Method: Charts of 145 adoles-
cents 13 - 18 years diagnosed with DSM-IV ADHD
and no specific reading disorder after a comprehen-
sive clinical and psycho-educational evaluation, were
reviewed to extract 1) word reading and word attack
subtest scores from the Woodcock-Johnson Achieve-
ment Test or the Wechsler Individual Achievement
Test; 2) Index scores from WISC-IV or WAIS-III IQ
tests; 3) scores from the Nelson-Denny Reading Test.
Results: Mean index scores for verbal comprehension
abilities not including reading were in the high aver-
age range, but working memory and processing
speed index scores were significantly weaker. Under
standard time limits 53% were unable to complete
the reading comprehension test and only 42.8% were
able to score within 1 SD of their IQ verbal compre-
hension index (VCI). When allowed extended time,
77.9% were able to score within 1 SD of their VCI.
T-test comparisons between standard time and ex-
tended time were significant at <0.001. Conclusions:
Allowing extended time for adolescents with ADHD
to complete tests involving reading may help to com-
pensate for their impairments of working memory
and processing speed, allowing them to score closer to
their actual verbal abilities.
Keywords: ADHD; Reading Comprehension; Extended
Time; Working Memory; Processing Speed
1. INTRODUCTION
Among adolescents with ADHD are some who report
chronic difficulties in reading that significantly impair
their ability to complete tests and assignments within
usual time allotments. Although most demonstrate no
significant impairment in phonological processing, the
usual hallmark of dyslexia, these students complain of
chronic slowness in assigned reading, due usually to a
need to re-read passages several times in order fully to
grasp the meaning. They also report that, though they
may understand the content at the time of reading a pas-
sage, they have chronic difficulty in recalling what they
have read just a few minutes earlier. It appears that
re-reading is needed to engage their focus sufficiently to
encode the information in memory. One student with
ADHD described this: “Most of the time when I’m read-
ing assignments in my textbooks, I’m just licking the
words rather than chewing them. That’s why I have to
keep going back to read it all over again.”
Interestingly, many of these students report that such
impairments often are not present when reading self-
chosen rather than assigned texts. This clinical observa-
tion suggests that such reading impairments may be the
result of impairments in executive functions (EF), which
tend to be situationally specific, rather than consistent
impairment in verbal abilities or basic reading skills.
Pennington [1] and Brown [2,3] have described the situ-
ational variability of executive functions impaired in
ADHD, how individuals with ADHD often demonstrate
little impairment in their ability to deploy executive
functions when doing tasks which hold strong personal
interest or anxiety for them, though they show much EF
impairment in most other situations. This is consistent
with findings by Anmarkrud and Braten [4] that stu-
dents’ motivation for reading content of personal interest
to them, the value they place on reading a specific text,
plays an important role in their reading comprehension.
In this study, we hypothesized that adolescents with

T. E. Brown et al. / Open Journal of Psychiatry 1 (2011) 79-87 80
ADHD who are slow in reading comprehension tasks
and do not have a specific learning disability in reading
would demonstrate relative weaknesses in working mem-
ory and processing speed, aspects of executive function
often impaired in ADHD. Further, we hypothesized that
extended time on a test of reading vocabulary and read-
ing comprehension would help these students to com-
pensate for their ADHD-related reading impairments,
yielding higher reading comprehension scores more con-
sistent with the individual’s verbal comprehension abili-
ties as shown on an IQ measure not involving reading.
There is considerable evidence that executive func-
tions often impaired in ADHD, especially processing
speed and working memory, play an important role in
reading, particularly in reading fluency and comprehen-
sion (see Willcutt [5], Shanahan [6], Laasonen [7],
McGrath [8], Arnell [9] and Swanson [10]). This is true
not only in those with a reading disorder, but also in
those who are not impaired in phonological processing
(see: Sesma [11], Locasio [12], Samuelson [13], Jacob-
son [14], Bental [15] and Leong [16]).
One specific executive function important in reading
comprehension is processing speed. Willcutt et al. [17]
demonstrated that impairment in processing speed is
found much more in children with reading disability
(dyslexia), in children with ADHD, and in those with
both disorders than in controls. In a sample of children
and adolescents Shanahan et al. [6] demonstrated that
processing speed, measured in multiple ways, is a shared
cognitive risk factor across reading disorder and ADHD
with a correlation of 0.7 between the two disorders. The
authors suggested that participants with each disorder
may be slowed down because they are engaging in a
speed-accuracy trade-off, buying increased accuracy
with a slower rate.
The study by Shanahan et al. utilized a variety of
measures to assess processing speed. These included
linguistic measures such as rapid automatized naming
(RAN) and the Stroop test as well as non-linguistic mea-
sures such as the WISC Coding subtest, the Trailmaking
test and the Stop-Signal task. Findings indicated that,
despite their differences, these various measures of pro-
cessing speed were highly correlated with one another,
all apparently reflecting a common factor that contrib-
utes to both ADHD and Reading Disorder.
Similar findings in a sample of adults in Finland were
reported by Laasonen, Leppamaki, Tani and Hokkanen
[7]. Their assessments of adults with dyslexia, attention
deficit disorder, and comorbid ADHD with dyslexia
found that all shared relative weakness in processing
speed as measured by the WAIS-III.
Primary importance of processing speed in overlap
between ADHD and reading disorder was also demons-
trated in a study by McGrath et al. [8]. They used multi-
ple deficit modeling with a sample of children with
ADHD and/or Reading Disorder. Their analysis identi-
fied processing speed as the most important common
factor between inattention and reading.
One measure of processing speed is the rapid automa-
tized naming (RAN) test, a timed measure of speed and
accuracy for naming familiar stimuli, e.g letters, digits,
colors, etc. randomly sequenced. The RAN has been
shown in numerous studies to predict reading compre-
hension. Arnell and colleagues [9] recently reported a
study using a sample of university undergraduates that
identified specific cognitive elements of the RAN that
contribute to its shared variance with reading compre-
hension. Their various measures explained 52% of the
variance shared by the RAN and reading comprehension
as measured by the Nelson-Denney Reading Test (NDRT).
Results suggested that working memory encoding is a
significant component of the relationship between proc-
essing speed measured by the RAN and reading ability.
Both processing speed and working memory have
been identified as important aspects of the complex cog-
nitive processes involved in reading comprehension.
Cain and Oakhill [18] reviewed multiple studies which
demonstrate that for skilled readers as well as for those
with poor reading skills or very limited reading compre-
hension, working memory plays a critical role in inte-
grating information to facilitate comprehension of text.
This is likely to be because comprehension depends upon
recalling what has been read in preceding sentences and
paragraphs so that the reader can develop and modify an
adequate working understanding of the message of each
section of the text and of how those components are re-
lated to one another.
Swanson, Zheng and Jerman [10] published a meta-
analysis of studies on working memory (WM), short-
term memory (STM) and reading disabilities. They de-
fined WM as “a processing resource of limited capacity
involved in the preservation of information while proc-
essing the same or other information (p. 260)”; they dif-
ferentiated this from STM, a resource in which small
amounts of information are held passively and then pro-
duced in an untransformed fashion, like the buffer of a
printer holding information from a computer prior to
printing. They noted that WM measures in these studies
were related primarily to reading comprehension of sen-
tences and paragraphs while STM measures related pri-
marily to recognition of individual words on a list.
Sesma, Mahone and colleagues [11] extended this view
in a 2009 study, noting that while some children have dif-
ficulty with reading comprehension because they have
chronic difficulty in decoding and accurately reading sin-
gle words, there are others who struggle with reading

T. E. Brown et al. / Open Journal of Psychiatry 1 (2011) 79-87 81
comprehension despite their having adequate ability to
decode and accurately read single words. These re-
searchers did a study with 60 children aged 9 to 15 years
with deficits in reading comprehension to test the hy-
pothesis that executive functions would be significantly
associated with reading comprehension skills, but not
with single word reading accuracy in children with word
reading deficits, reading comprehension deficits, and/or
ADHD.
Results indicated that executive skills differentially
support reading comprehension, but are less necessary
for single word reading. They explained their findings as
follows: “Reading comprehension is inherently more
complex than single word reading, with demands that go
beyond phonological decoding and word identification
and include higher order cognitive processing of mean-
ing conveyed through sentences and paragraphs… ex-
ecutive control skills such as planning and working
memory become more necessary as the length and com-
plexity of written text increases” (p. 8). A subsequent
study by these authors [12] of executive function im-
pairments in children with reading comprehension defi-
cits provided additional evidence that executive function
impairments, including planning and organizing, were
closely associated with impairments in reading compre-
hension. A significant proportion of the samples in both
of these studies were diagnosed with ADHD.
Similar findings about the role of executive function
impairments in reading comprehension of individuals
with ADHD was reported by Samuelsson, Lundberg and
Herkner [13]. In their study of male adults they found a
significant correlation between poor reading compre-
hendsion and ADHD while there was no significant as-
sociation between word decoding and ADHD. They ex-
plained this by arguing that word decoding “is deter-
mined by a smoothly operating, encapsulated… phono-
logical module largely unrelated to higher cognitive func-
tions such as executive controls” while “reading compre-
hension involves many of the higher cognitive control
functions assumed to be impaired in ADHD” (p. 165). In
a sample of 9 to 14 year old children with ADHD Ja-
cobson, et al. [14] (2011) demonstrated that both proc-
essing speed and working memory were significantly
associated with reading fluency.
The importance of working memory and processing
speed in reading comprehension is not limited to reading
in the English language. Using Hebrew language meas-
ures, Bental and Tirosh [15] evaluated a sample of Israeli
boys with ADHD only, Reading Disorder only, comorbid
ADHD + Reading Disorder, and controls, all of whom
were equivalent in oral language functions. They dem-
onstrated that reading performance in Hebrew by pre-
adolescent children with ADHD is linked to rapid nam-
ing and to executive functions, particularly verbal work-
ing memory, more than to phonological processing. A
large sample of preadolescent Chinese children showed
a similar pattern in a study by Leong, et al. [16] who
found that verbal working memory had a strong unique
effect on Chinese text comprehension, significantly gr-
eater than the influence of their ability to read pseudo-
words or rapid automatized naming (RAN).
Increasing recognition of the importance of working
memory and processing speed in reading comprehension
is consistent with a major shift emerging from research
on dyslexia. Shaywitz and Shaywitz [19] have empha-
sized how current research shows that reading is not
simply a modular process dependent only on phonologi-
cal processing needed to decode words. They argued that
reading must now be understood as involving also atten-
tional mechanisms that are essential to fluency and
automaticity in reading. “The critical requirement for
automaticity is for the reader to encode the relevant
items in memory and to retrieve them on a subsequent
encounter… for both encoding and retrieval, attention is
central (p. 1332).”
The Shaywitz paper also notes the importance of high-
er association cortices, particularly the prefrontal cortex,
in attentional mechanisms. Recognizing that “… atten-
tional mechanisms play a critical role in reading and that
disruption of attentional mechanisms plays a causal role
in reading difficulties (p. 1343)”, Shaywitz and Shaywitz
suggested that medications shown effective for improve-
ing attentional function in patients with ADHD “…
might be an effective adjunct to improving reading in
dyslexic students (p. 1329).” They also noted that “…
lack of automatic, fluent reading means that the dyslexic
reader may be able to decode words, but is still not able
to read quickly and continues to be at a disadvantage
compared to non-dyslexic peers when taking high-stakes
standardized tests such as SATs, Graduate Management
Admission Tests, Graduate Record Examination and so
forth (p. 1343).”
The comments of Shaywitz and Shaywitz focus on
dyslexic readers, but they are applicable to non-dyslexic
readers as well. Recent research such as studies cited
earlier in this paper clearly indicates that adequate read-
ing comprehension depends not only on ability to recog-
nize and decode words. It also depends upon 1) adequate
attention; 2) adequate working memory; and 3) adequate
processing speed. Typically, individuals with ADHD are
significantly impaired in all 3 of these critical executive
functions. One example is a study of fluency and reading
comprehension by Jacobson and colleagues [14] which
demonstrated that slow processing speed and impaired
working memory were significant predictors of difficult-
ties in reading fluency in children aged 9 to 14 years
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T. E. Brown et al. / Open Journal of Psychiatry 1 (2011) 79-87 82
with ADHD.
Our study reported here focused not on students who
suffer from dyslexia, but a sample of adolescents aged
13 to 18 years who did not suffer from a reading disorder.
This is an older group than those in most studies of
reading comprehension, an age group whose academic
work usually requires reading of longer, more complex
texts. All had been carefully diagnosed with ADHD and
were without a comorbid reading disorder. Students with
scores for basic reading skills below the low average
range were excluded from the study. We tested several
predictions about cognitive functions related to reading
comprehension difficulties in these adolescent students
diagnosed with ADHD. We also tested the effects of one
specific compensatory strategy that may be helpful to
many of these students… extended time for a reading
comprehension test.
Walczyk and colleagues [20] have reported research
testing a variety of compensatory strategies that have
been demonstrated helpful for readers at various skill
levels who are struggling for efficient comprehension of
a text. These compensatory strategies include slowing
down the reading rate; pausing to allow more time for
processing; looking back in the text to clarify confusion;
jumping over text segments that are confusing, but not
essential; and rereading of the text to enhance under-
standing. Regression analyses in their study revealed that
restriction of time to read a text tends to reduce compre-
hension because it does not allow sufficient opportunity
for the reader to clarify information to be processed in
working memory. This is consistent with clinical reports
of many students with ADHD who are unable to com-
plete exams within standard time allocation. Extended
time is one useful way to help students whose reading
comprehension is compromised by impaired working
memory and processing speed.
We predicted that students diagnosed with ADHD
would tend to be significantly weaker in working mem-
ory and processing speed than in their overall verbal
abilities exclusive of reading. This prediction was con-
sistent with findings of our study on executive function
impairments in children and adolescents with ADHD. It
was also consistent with findings reported by Mayes and
Calhoun [21] in their report of IQ index score predictors
of academic achievement. Their study used index scores
from WISC-III/IV to predict learning disorders (LD)
with a discrepancy formula using the Wechsler Individ-
ual Achievement Test-Second Edition (WIAT-II). From a
large sample of youths 6 - 16 yrs they reported that the
most powerful predictor of academic achievement was
the Verbal Comprehension Index and that the most pow-
erful predictors of LD were the index score for Working
Memory/Freedom from Distractibility and the index
score for Processing Speed.
We also predicted that our sample of students with
ADHD and without a specific LD in reading would have
relatively unimpaired basic reading skills (within 1 SD
of their verbal comprehension index on the WISC/
WAIS) but would tend to score relatively low on a timed
test of reading comprehension (≥1 SD below their ver-
bal comprehension index). When allowed extended time
on a reading comprehension test, we predicted that their
score would be closer to their VCI.
2. METHODS
2.1. Sample
Records of two ADHD specialty clinics in a metropolis-
tan area of the Northeast U.S., one private, the other in a
university medical center were reviewed to select charts
of all individuals 13 to 18 years who sought consultation
for attention or learning problems, met DSM-IV diag-
nostic criteria for ADHD, had undergone a full psy-
cho-educational evaluation within the past three years,
and did not have any specific learning disorder in read-
ing.
Potential participants were excluded if their basic
reading skills as measured by WIAT-II or WJ-III word
reading or pseudoword decoding (word attack) scores
were below 80, or if their vcrbal comprehension index
score on the WISC or WAIS was below 80. Thus par-
ticipants were all non-dyslexic students with verbal
comprehension abilities (not including reading) in the
low average range to superior range who suffered sig-
nificant current impairments from ADHD sufficient to
warrant diagnosis under DSM-IV diagnostic criteria. The
sample included 145 participants aged 13 to 18 years;
69.1% were males. The mean for VCI was 118.6; the
mean for POI was 112.6.
Evaluation protocols in both clinics were identical. A
licensed clinical psychologist experienced in assessing
ADHD and related disorders conducted a two hour
clinical interview of the patient with one or both parents
to take relevant history and assess impairment according
to DSM-IV-TR diagnostic criteria for ADHD. A normed
and validated rating scale for ADD and related executive
functions, the Brown ADD Rating Scale, [22,23] was
administered and screening for possible comorbid dis-
orders was completed. In a separate session after ADHD
diagnosis, the full WISC-IV [24] or WAIS-III [25] IQ
tests were administered followed by the Wechsler Indi-
vidual Achievement Test (WIAT-II) [26] or the Wood-
cock-Johnson 3rd Edition Achievement Tests [27].
2.2. Measures
To assess basic reading skills, we used standardized
measures of word reading and pseudoword reading (word
attack) from the Woodcock-Johnson Achievement Test

T. E. Brown et al. / Open Journal of Psychiatry 1 (2011) 79-87 83
(WJ-III) or the Wechsler Individual Achievement Test
(WIAT-II). These were compared with the student’s
overall verbal abilities as measured by the Verbal Com-
prehension Index (VCI) of the student’s WISC or WAIS
IQ tests, a measure of verbal ability not requiring read-
ing. The VCI was used as a basis for comparison be-
cause it is a validated and normed measure of verbal
comprehension abilities that does not require any read-
ing.
To assess processing speed and working memory, we
used two index scores from the student’s WISC or WAIS:
Working Memory Index (WMI) and Processing Speed
Index (PSI), neither of which involves reading, Mayes
and colleagues [28] have shown, in their own research
and have cited other studies showing that children with
ADHD tend to score significantly lower on WMI and
PSI than comparison children and significantly lower
than their own Verbal Comprehension index.
To assess the impact of extended time for reading
comprehension, we used the Nelson-Denny Reading Test
[NDRT] [29], a normed measure which requires each
subject to complete 80 multiple choice vocabulary ques-
tions within 15 min. Each is then asked to read 7 narra-
tive passages and answer 38 multiple choice compre-
hendsion questions within 20 min. Any individual unable
to complete the vocabulary section is allowed up to 9 ad-
ditional minutes; anyone unable to complete the com-
prehension section is allowed up to 12 additional minutes.
2.3. Data Analysis
To allow for comparison of NDRT and WAIS/WISC
scores, the percentile ranks of the NDRT were converted
to a normal-curve scale that matched the mean (100) and
SD (15) of IQ and Index scores. We scored results ob-
tained with extended time using the NDRT norms for
standard time. Our procedure differs from the Extended
Time tables used in the NDRT, but our procedure with
this scoring is similar to that of Ofiesh, et al. [30] and
closely mirrors what is done when the accommodation
of extended time is allowed, i.e., scores are ranked on
the same metric. Students given extended time accom-
modations for standardized measures such as the SAT
and ACT are scored on the same metric as students
without accommodations. They are not penalized by be-
ing scored with separate norms applicable only to those
receiving extended time.
We compared each student’s scores for reading vo-
cabulary and reading comprehension on the NDRT under
both standard time and extended time conditions (using
the NDRT norms for standard time) with their basic
reading abilities and their overall cognitive abilities as
measured by the VCI. We then used paired t-tests to as-
sess significance.
We chose the verbal comprehension index as the
standard for comparison because it is an age-based and
validated measure of verbal comprehension abilities
that does not require any reading. Normative data from
the WIAT-II show that VCI is a reasonable predictor of
reading comprehension. Only 11% - 12% of individu-
als score more than 1 standard deviation below their
WISC/WAIS VCI on a standardized measure of read-
ing comprehension [26].
3. RESULTS
Overall verbal skills of these students on tests not in-
volving reading were relatively strong.
As shown in Figure 1, their WISC-IV/ WAIS-III Ver-
bal Comprehension Index (VCI) mean was in the high
average range: 118.6 (13.8). As predicted, and as is com-
mon among individuals diagnosed with ADHD, their
mean index scores for Working Memory (WMI) and
Processing Speed (PSI) were both more than 1 SD lower,
in the average range: WMI: 102.8 (14.2); PSI: 99.9
(16.3). These scores indicate relative weakness in these
two index scores that tap executive functions associated
with ADHD and are significantly lower than the VCI (p
= < 0.0001).
It should be noted that this sample was not strong only
in verbal comprehension and weak in all other factors of
measured IQ. Their mean score for Perceptual Organiza-
tion Index (POI) was in the high average range, 112.6
(12.6), just 6 points lower than their mean VCI. This dis-
crepancy is not significantly different from the stan-
dardization samples for the WISC-IV or WAIS-III [26].
These students were in the high average range for the two
factors of Wechsler IQ tests less sensitive to im- pairments
of executive function. Like most individuals with ADHD,
they were relatively weak in their scores for WMI and PSI,
the two factors of these IQ tests that are more sensitive to
executive function impairments [21].
Also shown in Figure 1 are mean scores for basic
Figure 1. Basic reading vs. IQ verbal abilities vs. executive
functions.
C opyright © 2011 SciRes. OJPsych

T. E. Brown et al. / Open Journal of Psychiatry 1 (2011) 79-87 84
reading skills on the WJ-III/WIAT-II, word recognition
and word attack, which were solidly in the average range:
word recognition: 106.5 (11.05) word attack: 106.8
(13.4). These scores indicate that basic reading skills of
this sample were somewhat lower than their VCI, but
still solidly in the average range. Reading difficulties of
this group were not due to significant impairments in
ability to use phonics principles to decode unfamiliar
words or to impairments in ability to recognize and cor-
rectly pronounce words from an age-appropriate vo-
cabulary list.
This is consistent with the findings of other studies
(see: Sesma [11], Locasio [12] and Jacobson [14]) dem-
onstrating that problems with reading comprehension
exist independently in some students with fully adequate
basic reading skills. Reading comprehension problems
are not limited to those with weak decoding and/or sight
vocabulary. Reading comprehension requires adequate
decoding skills, but it also requires adequate executive
functioning, especially in working memory and process-
ing speed, two areas typically weak in individuals with
ADHD.
Figure 2 displays comparisons of participants’ mean
scores for VCI and their mean scores for the NDRT un-
der standard and extended time. Scores for the vocabu-
lary section with standard time were 10.6 (15.1) points
below their VCI. When those who were unable to finish
the vocabulary section were allowed extended time, the
discrepancy between mean VCI and mean vocabulary
score reduced to 8.2 points (12.1).
Under standard time the mean score for the NDRT
comprehension section was 17.7 points lower than the
mean VCI. As predicted, scores of these ADHD students
improved significantly when they were allowed the ex-
tended time on the reading comprehension section,
yielding a discrepancy of just 7.4 (13.1). Paired t-tests on
both comparisons yielded p = < 0.0001.
In addition to comparing group means, we also as-
sessed individual performances on these measures. Each
Figure 2. Standard vs. extended time vs. IQ verbal abilities
group means.
participant’s score for vocabulary and for comprehension
on the NDRT under standard time was compared with
his scores on these measures when allowed extended
time. In both cases, obtained scores on the NDRT were
compared with that individual’s VCI score on the IQ test.
Thus we assessed the degree to which that individual’s
performance on the NDRT resembled his score for basic
verbal comprehension abilities.
Figure 3 shows that under standard time conditions
for vocabulary items, 63.4% of the sample obtained a
score on the NDRT within one SD of their VCI score; for
reading comprehension items, only 42.8% were within
that range. This can be compared to the normative data
from the WIAT which shows that only 11% - 12% of
individuals scored one SD or more below their VCI on a
standardized measure of reading comprehension.
When those unable to finish in standard time allot-
ments were allowed the stipulated amount of extended
time to finish, scores within 1 SD of their VCI were ob-
tained by 72.9% for vocabulary and by 77.9% for com-
prehension, much closer to the percentage in the general
population that would be expected to have such a dis-
crepancy.
4. DISCUSSION
While many of these 145 adolescents with ADHD were
able to complete the NDRT within standard time con-
straints, 48% were unable even to attempt all the vo-
cabulary questions and 53% were unable to attempt all
of the reading comprehension questions without ex-
tended time. This is consistent with our clinical experi-
ence that many, but not all students with ADHD report
chronic difficulty in completing tests, particularly tests
involving substantial reading, within standard time limits.
The high average mean verbal comprehension index
scores of this sample and their solidly average mean
scores for basic reading skills may limit generalizability
of our results, but they do support our prediction that
Figure 3. Percentage of subjects scoring within 1 sd of their iq
verbal ability index standard time vs. extended time.

T. E. Brown et al. / Open Journal of Psychiatry 1 (2011) 79-87 85
their difficulty with the reading test used was not likely
to be a result of weaknesses in basic verbal abilities or
weaknesses in basic reading skills. It appears more likely
that their significant relative weaknesses in processing
speed and working memory, aspects of the executive
functions often impaired in ADHD, contributed to their
relatively low scores on our reading measure adminis-
tered with just standard time.
These data provide evidence that on tests involving
reading longer, more complex texts under time con-
straints, allowing a modest extension of time can provide
individuals with ADHD opportunity to demonstrate
reading comprehension abilities more consistent with
their actual verbal abilities. This accommodation can
help these students to compensate for the chronic prob-
lems with working memory and processing speed that,
for such tasks, burden many, though not all, adolescents
with ADHD.
Some might question whether allowing extended time
on exams, particularly high stakes exams that may im-
pact admission to university or graduate studies, would
be providing ADHD students with an unfair advantage.
This is an issue that is complex and remains controver-
sial due to conflicting research findings, many due to
methodological differences between studies. Lovett [31]
has highlighted central issues in the controversy over
extended time accommodations and has reviewed some
of the evidence to draw conclusions about the way ex-
tended time accommodations are currently provided. He
argues for developing tests using principles of universal
design so that all students can take the tests in the same
format.
Sireci, Scarpati and Li [32] have provided a compre-
hensive review of studies that attempted to address the
issue of test accommodations for students with disabili-
ties and how they impact both students identified with
disabilities and those without disabilities who do not
receive accommodations. Their review supported the
contention that extended time helps students with dis-
abilities. They also found that extra time tends to impr-
ove the performance of all students, not just those with
disabilities. However, they noted that students with dis-
abilities tend to experience more substantial gains from
extended time than do their non-disabled counterparts.
They suggested further research to consider whether
time limits should be extended for all students on most
tests.
The purpose of this study was not to try to resolve the
complex issues of fairness in allowing or denying use of
accommodations to students with various types of im-
pairments. It is to test hypotheses about the impact of
ADHD-related executive function impairments on read-
ing comprehension of adolescent students with ADHD
and regarding the potential benefits of extended time for
these students when taking tests requiring reading com-
prehension of more complex texts.
Our study indicated that many, but not all of our partici-
pants with ADHD were unable to complete one or both
sections of the NDRT within standard time allotments. This
suggests that some diagnosed with ADHD do not need
extended time on tests such as the NDRT, though many
do need extended time to have a fair chance to show
what they know and can do.
These findings suggest that clinicians screening indi-
viduals for ADHD should include in their evaluation
specific inquiries about reading comprehension, speed of
reading, memory for what has been read, and whether
the individual can usually finish tests and exams within
usual time constraints. In making such inquiries, it is
important that the clinician ask about assigned reading as
distinguished from reading of self-chosen materials in
which the person has strong personal interest.
As mentioned in the introduction to this paper, the
situational variability of executive function impairments
associated with ADHD can result in very different levels
of functioning for self-chosen vs. assigned reading tasks
[2]. For patients who report significant difficulties in
reading speed, recall and comprehension of what has been
read, or difficulty in completing tests or exams within
standard time allotments, a more comprehensive assess-
ment of reading, working memory and processing speed
is usually indicated.
Current regulations on most high-stakes testing requi-
re clinical diagnostic interviews and a battery of psycho-
educational testing for persons requesting extended time
for such exams based on diagnosis of ADHD or a spe-
cific learning disorder. Such an assessment seems appro-
priate to establish need for extended time, but this re-
quirement is problematic for students who cannot afford
the high costs of such testing which often is not covered
by insurance. The requirement is also problematic for
those who do not have access to psychological evaluat-
ors who have the appropriate expertise.
4.1. Limitations of the Study
Findings from this study should be understood in light of
limitations of the study.
First, this sample is characterized by students who
tended to have high average verbal comprehension abili-
ties. Applicability to students with different levels of verbal
comprehension may be limited and remains to be tested.
The Nelson-Denny Reading Test has been criticized
for having a low ceiling which does not provide ade-
quate challenge for students of stronger ability who may
be required in their schooling to read and take tests in-
volving much more complex text than is provided by the
C opyright © 2011 SciRes. OJPsych

T. E. Brown et al. / Open Journal of Psychiatry 1 (2011) 79-87 86
Nelson-Denny. Also, one study by Coleman, et al. [33]
found that a sample of students with and without dis-
abilities were able to obtain scores well above chance on
this test without having read the passages on which the
comprehension questions are based.
However, despite its limitations, the NDRT is one of
the few reading tests currently available that provides
passages of text that extend for several paragraphs. Most
other reading comprehension tests currently available
attempt to test reading comprehension, even for adoles-
cent and adult students, using very short passages or, in
some cases, single sentences that bear little relationship
to the longer, more complex readings required even of
junior high and high school students, not to mention
students in college or university programs. The NDRT
also offers two normed versions and provides a useful
measure for both a standard and extended time condi-
tions.
Clearly more adequate normed measures are needed,
but at this time the NDRT, despite its very real limita-
tions, provides a more challenging normed measure of
reading comprehension for adolescents and adults than
do most other measures of reading comprehension avail-
able at this time.
5. CONCLUSIONS
Given the findings of this study, it would seem advisable
for clinicians assessing individuals with ADHD to in-
quire directly about whether they are able to complete
tests involving reading comprehension within the time
usually allowed. If the student reports frequent inability
to complete such tests, the student should be referred for
a full psychoeducational evaluation, including the NDRT
or a comparable measure, to establish whether accom-
modations including extended time for tests and exami-
nation are appropriate and should be provided.
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