Prevalence of Attention-Deficit/

Hyperactivity Disorder: A Systematic

Review and Meta-analysis
Rae Thomas, BEd, PhD, Sharon Sanders, BScPod, MPH, Jenny Doust, MBBS, PhD, Elaine Beller, BSc, MAppStat,
Paul Glasziou, MBBS, PhD

abstract Overdiagnosis and underdiagnosis of attention-deficit/hyperactivity

BACKGROUND AND OBJECTIVE:
disorder (ADHD) are widely debated, fueled by variations in prevalence estimates across
countries, time, and broadening diagnostic criteria. We conducted a meta-analysis to: establish
a benchmark pooled prevalence for ADHD; examine whether estimates have increased with
publication of different editions of the Diagnostic and Statistical Manual of Mental Disorders
(DSM); and explore the effect of study features on prevalence.
METHODS: Medline, PsycINFO, CINAHL, Embase, and Web of Science were searched for studies
with point prevalence estimates of ADHD. We included studies of children that used the
diagnostic criteria from DSM-III, DSM-III-R and DSM-IV in any language. Data were extracted
on sampling procedure, sample characteristics, assessors, measures, and whether full or
partial criteria were met.
RESULTS: The 175 eligible studies included 179 ADHD prevalence estimates with an overall
pooled estimate of 7.2% (95% confidence interval: 6.7 to 7.8), and no statistically significant
difference between DSM editions. In multivariable analyses, prevalence estimates for ADHD
were lower when using the revised third edition of the DSM compared with the fourth edition
(P = .03) and when studies were conducted in Europe compared with North America (P = .04).
Few studies used population sampling with random selection. Most were from single towns
or regions, thus limiting generalizability.
Our review provides a benchmark prevalence estimate for ADHD. If population
CONCLUSIONS:
estimates of ADHD diagnoses exceed our estimate, then overdiagnosis may have occurred for
some children. If fewer, then underdiagnosis may have occurred.

Centre for Research in Evidence-Based Practice (CREBP), Faculty of Health Sciences and Medicine, Bond University, Queensland, Australia

Dr Thomas, Ms Sanders, Dr Doust, and Dr Glasziou conceptualized and designed the study; Dr Thomas led the review process, drafted the initial manuscript, and with
Ms Sanders reviewed all articles and extracted data; and Dr Beller and Dr Thomas analyzed and interpreted the data. All authors made substantial contributions
to revising the manuscript and approved the final manuscript as submitted.
www.pediatrics.org/cgi/doi/10.1542/peds.2014-3482
DOI: 10.1542/peds.2014-3482
Accepted for publication Jan 28, 2015
Address correspondence to Rae Thomas, BEd, PhD, Centre for Research in Evidence-Based Practice (CREBP), Faculty of Health Sciences and Medicine, Bond University,
2 University Dr, Gold Coast, Queensland, Australia 4229. E-mail: rthomas@bond.edu.au
PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).
Copyright © 2015 by the American Academy of Pediatrics
FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose.
FUNDING: No external funding.
POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.

REVIEW ARTICLE Downloaded from http://pediatrics.aappublications.org/ by guest on MayPEDIATRICS

2, 2018 Volume 135, number 4, April 2015
Considerable debate exists vary when only some of the estimates of ADHD between DSM-III,
surrounding the diagnosis of diagnostic criteria are fulfilled DSM-III-R, and DSM-IV and that
attention-deficit/hyperactivity compared with full criteria being differences in study methods would
disorder (ADHD), with claims for the met.14,15 Prevalence estimates for account for significant variations in
condition being both underdiagnosed1 ADHD can be reduced by more than prevalence estimates.
and overdiagnosed.2,3 Prevalence one-half when full criteria are used.
estimates of ADHD within and For example, differences between METHODS
between countries often vary widely,4 DSM editions include the criterion of
and reports of increases in pervasiveness: the Diagnostic and Inclusion and Exclusion Criteria
prevalence5 further fuel the Statistical Manual of Mental Disorders, The searches were conducted for
controversy. Prevalence estimates are Revised Third Edition (DSM-III-R), studies with point prevalence
important because high estimates are requires symptoms to manifest estimates of ADHD. Eligible studies
often widely reported and provide usually (but not necessarily) in .1 were those that used the diagnostic
anchors for parents and diagnosing setting, whereas the Diagnostic and criteria from DSM-III, DSM-III-R, or
clinicians. Concern has also been Statistical Manual of Mental Disorders, DSM-IV with samples from
expressed regarding the effect of Fourth Edition (DSM-IV), requires community or school populations, or
widening diagnostic criteria with more symptoms be present in $2 settings. using a whole population approach
recent editions of the Diagnostic and DSM-IV includes a criterion of (eg, national surveys). We included
Statistical Manual of Mental Disorders clinically significant impairment. studies of any language and with
(DSM).6,7 Given the controversy of In the past decade, 5 systematic participants aged #18 years.
whether ADHD is overdiagnosed or reviews have been conducted Intervention or treatment studies
underdiagnosed and the true regarding prevalence estimates of were excluded.
prevalence rate of the disorder, we ADHD: 3 descriptive reviews16–18 and
conducted a systematic review to Search Strategy
2 meta-analyses.9,13 However, the
estimate the prevalence of ADHD and latter 2 studies are limited by the The databases of Medline, PsycINFO,
to examine factors that may explain following factors: (1) studies were CINAHL, Embase, and Web of Science
the variations in prevalence. restricted to only 5 languages; (2) the were searched by using Medical
Five editions of the DSM have been method of measurement (eg, Subject Headings terms and key
published, and reports of increases in symptom only questionnaires words to identify potentially eligible
ADHD prevalence have been made compared with interviews) as studies (Supplemental Box 1). Key
with each new edition since potentially affecting prevalence was words included attention deficit,
publication of the Diagnostic and not considered; (3) prevalence ADHD, hyperactivity, disorder,
Statistical Manual of Mental Disorders, studies using DSM-IV criteria only epidemiology, point estimate, child,
adolescent, survey, and prevalence.
Third Edition (DSM-III).7–9 Even when were included; and (4) the impact of
No language, date, or publication
diagnoses are made by using the study variables on prevalence
restrictions were used.
same DSM edition, variations in estimates were not investigated. The
prevalence are reported. For example, present study is the first to Study Selection and Data Extraction
the United States has conducted statistically compare the prevalence
Our search yielded 5134 unique
multiple nationwide studies that estimates of ADHD over time between
citations (Fig 1). All studies were
provide estimates of ADHD different editions of the DSM.
screened against the eligibility
prevalence. When aggregated, these Our aim was to answer 3 research criteria by 2 independent reviewers
findings suggest statistically questions: (1) What is the pooled (R.T. and S.S.) by using screening
significant differences in prevalence prevalence estimate of ADHD in software (DistillerSR, Evidence
estimates, both between states and children according to DSM criteria? Partners, Ottawa, Ontario, Canada).
within the overall national estimate.10 (2) Have prevalence estimates of Conflicts were resolved through
How different studies assess ADHD ADHD increased over time when discussion. Data were independently
may affect reported prevalence differing DSM diagnostic criteria have extracted by the same 2 reviewers
estimates; for example, the person been used? (3) What is the effect regarding general publication
reporting symptoms for a diagnostic of different sampling frames, information, DSM edition used for
evaluation (parent, teacher, or child) informants, measurements, full diagnosis, country, language of
and with what instrument11,12 and versus partial criteria, and regions publication, sampling procedure
when .1 informant is used, how the on prevalence estimates? We (eg, random selection, cohort), year
information is combined.9,13 hypothesized that there would be of sampling (or publication date if
Estimates of ADHD prevalence also significant increases in the prevalence sampling year not reported),

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 prevalence estimate was extracted.
Finally, if a study reported several
prevalence estimates for ADHD based
on full or partial criteria, data were
extracted by using the most
comprehensive criteria available
(eg, we extracted full criteria instead
of partial, severe instead of moderate
ADHD, and clinical instead of
subthreshold).
Prevalence studies often used .1
informant (eg, parent, teacher, child)
to identify children or adolescents
with ADHD symptoms. The most
conservative estimate was again
used: the “and rule” (positive if
endorsed by $2 informants [usually
the parent or the teacher]). We also
coded whether the study used an
“or rule” (positive if endorsed by
either informant). The informant
was coded as “clinician” if the final
stage of screening required
a diagnostic interpretation of
a clinical interview.
Risk of bias was assessed by using
a modified tool developed by Hoy
et al19 for assessing this variable in
prevalence studies. One risk of bias
FIGURE 1 item from Hoy et al19 required
Preferred Reporting Items for Systematic Reviews and Meta-analyses flow diagram. studies use an acceptable case
definition. As we used studies that
reported DSM criteria, we considered
sampling frame, demographic study. The most conservative this item irrelevant to our review and
variables of sample, informant, diagnosis was used in those studies it was not included. We also limited
measures used to make diagnosis reporting .1 estimate. Several response options to a forced choice
(ie, symptom only checklists, reports studies reported lower prevalence of of “low risk” or “high risk.” Risk of
of diagnosis by others, interviews that ADHD when children were the bias criteria included items regarding
were not necessarily conducted by informant compared with parent,13,16 the representativeness of sample,
clinicians), and whether the diagnosis parent compared with teacher,11,13 sampling frame, random selection,
met the full DSM criteria for each and clinicians were reported to nonresponse bias, informant, and
edition (ie, age of onset and duration estimate the lowest prevalence measurement reliability and validity.
for DSM-III; age of onset, duration, compared with any other The more criteria were met, the lower
and symptoms manifest in at least 1 informant.9,13 Therefore, if a study the risk of bias. If the text was
setting for DSM-III-R; age of onset, reported prevalence estimates from unclear, a high risk of bias was then
different informants, we chose child
duration, symptoms manifest in $2 recorded. A study was considered to
over parent or teacher, a parent over have a high overall risk of bias if #3
settings, and clinically significant
teacher, and a clinician over any other criteria were met, moderate risk of
impairment for DSM-IV). The number
informant. If the study was bias if 4 or 5 criteria were met, and
of children/adolescents identified as
longitudinal with multiple prevalence low risk of bias if studies met 6 to
having ADHD was extracted, and
estimates over time in the same 8 criteria.
prevalence was calculated by dividing
sample, the first prevalence estimate
this number by the total sample size. was chosen. If a study reported Statistical Analyses
Only 1 prevalence estimate for each different prevalence estimates for Data were analyzed by using Stata
DSM edition was extracted for each different ages, the combined version 11.1 (Stata Corp, College

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Station, TX). Because there were in the overall pooled result and the (82%, 62%, and 39%) and a
many small studies with low meta-regression analysis. corresponding increase in a reliance on
prevalence estimates, SEs of the symptom only criteria (9%, 33%, and
prevalence estimates from each study 42%). There was also a decrease in
were calculated based on the exact RESULTS the use of full criteria compared with
binomial likelihood.20 Summary effect A total of 175 unique studies were partial criteria from DSM-III to DSM-III-R
estimates of prevalence were included that contributed 179 to DSM-IV (82%, 62%, and 37%).
calculated by using a meta-analysis estimates of prevalence in 1 023 071 Although most studies (75%) were at
with a random effects model. Studies subjects over 36 years (Fig 1). Study moderate or low risk of bias, no
were grouped according to DSM characteristics are depicted in Fig 2, studies met all 8 criteria, and only
editions, and the estimates were and characteristics of all included 17% were at low risk of bias (Fig 3).
then pooled. We used z tests of studies are provided in Supplemental The majority of studies rated poorly
2 proportions to examine differences Table 2. Overall, there was a broad for likelihood of nonresponse bias
in prevalence estimates of studies by geographical distribution of studies, (88%) and representativeness of
using different DSM criteria. The although the greatest proportion of sample (84%), and most studies did
study factors were investigated that studies were conducted in Europe not collect ADHD diagnostic
might be related to prevalence (31%). A majority of studies were information directly from children or
estimate by using meta-regression conducted within school populations adolescents (68%). Summary statistics
analyses. Study factors included (74%), and few used a whole for risk of bias for studies included
sample size, sampling frame, population approach (10%). The in each DSM edition are provided in
informant, measurement (symptom methods used in the studies varied Supplemental Figs 5, 6, and 7.
only, report of diagnosis, interview, or over time, with the use of clinicians
unclear), study region, and full versus falling from 55% in DSM-III studies to
partial criteria. Three studies 28% in studies using DSM-IV criteria. Overall Prevalence of ADHD
compared prevalence estimates by Parents were used as informants in The overall, pooled prevalence of
using different DSM criteria: DSM-III more than twice as many studies ADHD including all editions of the
with DSM-III-R, DSM-III with using DSM-IV compared with DSM was 7.2% (95% confidence
DSM-III-R and DSM-IV, and DSM-III-R DSM-III-R criteria (29% and 12%, interval [CI]: 6.7 to 7.8]). Within the
with DSM-IV. These studies were respectively) and .3 times compared univariable models, prevalence
included in analyses for each DSM with DSM-III criteria (9%). There was estimates of ADHD were, on average,
prevalence estimate, but only 1 a general decrease in the use of 3% lower when diagnoses were made
estimate (based on the earliest interviews as a measurement tool with DSM-III-R criteria than with
published DSM edition) was included from DSM-III to DSM-III-R to DSM-IV either DSM-III or DSM-IV criteria

FIGURE 2
Characteristics of included studies.

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FIGURE 3
Number and percentage of included studies addressing risk of bias (RoB) questions (N = 178).

(P = .008), 2% higher when symptom 96.9% and 99.3%). Despite the approval dates of significant ADHD
only checklists were used rather than different prevalence estimates, the medications, and the year direct-
clinical interviews (P = .02), and 4% pooled prevalence was not statistically to-consumer advertising commenced
higher when children were diagnosed significantly different between in the United States. When a new
in the Middle East compared with editions of the DSM (DSM-III to DSM edition was published, it was
North America (P = .002) (Table 1). DSM-III-R, P = .9; DSM-III-R to DSM-IV, followed by an increased publication
No other variables were statistically P = .6; DSM-III to DSM-IV, P = .8). of studies with prevalence estimates
significant. After entering all of ADHD with a publication lag
statistically significant variables into Impact of Study Variables on time. Most studies with a prevalence
Prevalence Estimates for Different
a multivariable meta-regression, only estimate of ADHD .10% occurred
DSMs
DSM edition and region remained using the diagnostic criteria of DSM-IV.
significant. After adjusting for In univariable meta-regressions for
measurement and region, prevalence studies conducted with DSM-III
criteria, there was a significant Sensitivity Analysis and Potential
estimates for ADHD were, on average,
increase in prevalence estimates Bias
2% lower when using DSM-III-R
compared with DSM-IV criteria when the informants were parents Sensitivity analyses were conducted
(P = .03) and 2% lower in studies compared with clinicians (parents’ with the 32 studies (contributing
conducted in Europe compared with estimates were, on average, 33 prevalence estimates) that were
North America after adjusting for DSM 8% higher, P = .03). However, no other at the lowest risk of bias. The
edition and measurement (P = .04). study variables were significant. In prevalence estimate of ADHD in these
studies establishing the prevalence of studies was slightly higher at 7.8%
Changes in Prevalence Using ADHD by using DSM-III-R criteria, no (95% CI: 6.6 to 9) but not statistically
Different DSMs study variables helped explain different from the overall pooled
There was a wide range of prevalence heterogeneity. When using DSM-IV prevalence (P = .95). Prevalence
estimates for each DSM. DSM-III criteria, only the region in which the estimates of low risk of bias studies
prevalence ranged from 1% to 12% study was conducted was significant; ranged between 1% and 20%.
and had a pooled prevalence of 5.6% the Middle East had, on average, Heterogeneity remained significant
(95% CI: 3.7 to 7.5). DSM-III-R 3% higher prevalence estimates of (I2 = 99.5%), and there were no
estimates ranged from 0.3% to 11% ADHD than North America (P = .02). statistically significant differences
with a pooled prevalence of 4.7% between prevalence estimates
(95% CI: 3.3 to 6.0). DSM-IV had the Changes in Prevalence Over Time according to the various DSM editions.
widest prevalence range (between Figure 4 plots the prevalence Prevalence estimates were compared
0.2% and 34%) with a pooled estimates of ADHD between 1977 and with study sample size (Supplemental
prevalence of 7.7% (95% CI: 7.1 to 2013 according to year of study Fig 8), similar to a funnel plot, to
8.4). There was significant publication. Also shown are the year detect publication or methodologic
heterogeneity across all studies in of DSM publication, the year of bias. Almost all of the studies with
each DSM edition (I2 ranged between US Food and Drug Administration smaller samples (between 100 and

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TABLE 1 Association Between Study Variables and ADHD Prevalence Estimates Willcutt13 also conducted meta-
Study Variable Univariate Analyses Multivariate Analyses With analyses for prevalence estimates of
Significant Predictors ADHD. The author categorized the
Coefficient 95% CI P Coefficient 95% CI P
prevalence estimates according to
informant, with the lowest prevalence
DSM edition (RC: DSM-IV)
DSM-III-R 23% –0.05 to –0.01 .008 22% –0.05 to 0.00 .03
estimate reported for clinicians (5.9%
DSM-III 22% –0.05 to 0.01 .18 21% –0.04 to 0.02 .60 “best estimate”) and the highest for
Sample size 0% –0.00 to 0.00 .17 — — — teachers using measurements that
Origins of sample (RC: population) assessed symptoms only (13.3%).
Community 21% –0.04 to 0.03 .72 — — — Our estimate is within this range.
School 2% –0.01 to 0.04 .17 — — —
Informant (RC: clinician) Although pooled estimates were not
AND rule 0% –0.03 to 0.03 .85 — — — statistically significantly different
OR rule 0% –0.04 to 0.03 .79 — — —
between DSM editions, prevalence
Parent 0% –0.02 to 0.02 .79 — — —
Teacher 1% –0.01 to 0.04 .19 — — — estimates were smaller when studies
Child 22% –0.06 to 0.02 .24 — — — used the DSM-III-R criteria for
Unclear/not reported 21% –0.05 to 0.07 .71 — — — diagnosis of ADHD. It is possible
Measurement (RC: interview) that the inclusion of subtypes in both
Symptom only 2% 0.00 to 0.04 .02 1% –0.00 to 0.03 .11
DSM-III and DSM-IV criteria allow
Reports of diagnosis 21% 0.03 to 0.02 .59 21% –0.04 to 0.01 .36
Unclear/ not reported 0% –0.04 to 0.04 .82 0% –0.04 to 0.04 .92 for a broader group of children to
Criteria be diagnosed with the disorder that
Partial versus full 1% –0.01 to 0.02 .32 — — — our study has not had the power to
Country region (RC: North America) detect. When different DSM criteria
Europe 21% –0.04 to 0.01 .15 22% –0.05 to 0.00 .04
were considered simultaneously in
Asia 22% –0.05 to 0.01 .12 22% –0.05 to 0.00 .08
South America 2% 0.00 to 0.05 .10 1% –0.02 to 0.04 .55 a univariable and multivariable
Oceania 23% –0.07 to 0.01 .13 23% –0.07 to 0.01 .12 analysis, studies using the criteria
Middle East 4% 0.02 to 0.06 .002 2% –0.00 to 0.05 .09 of DSM-III-R had significantly lower
Africa 21% –0.05 to 0.03 .70 23% –0.07 to 0.02 .21 ADHD prevalence than studies using
South Asia 21% –0.05 to 0.03 .65 22% –0.06 to 0.03 .39
either DSM-III or DSM-IV criteria.
RC, reference category; —, variable not included in multivariable analyses.
The only other study characteristic
that contributed to the variation in
5000 participants) and with a change in the prevalence of ADHD prevalence estimates was region.
prevalence estimates .10% used over time and after publication of Estimates of ADHD prevalence were
DSM-IV diagnostic criteria. Of the new DSM editions. Anecdotally, and greater in the Middle East compared
75 studies with ,1000 participants, using data from physician outpatient with North America in univariable
23 studies reported prevalence registries,21 the number of children analyses; multivariable analysis
estimates of .10%. Of these, all but diagnosed with ADHD seems to have studies conducted with participants
2 (91%) were studies that used increased. However, contrary to our from Europe had lower prevalence
DSM-IV criteria for ADHD diagnosis. hypothesis, the estimates of estimates of ADHD compared with
Similarly, of the 80 studies with prevalence did not statistically North America. Unexpectedly, sample
sample sizes between 1001 and 5000, significantly increase over time nor size, sampling frame, informant, and
18 studies reported a prevalence were they statistically significantly measurement did not account for
estimate of .10%; of these, 17 (94%) different between the various DSM differences in prevalence estimates.
were studies that used DSM-IV editions.
criteria. A post hoc x2 analysis Our study has several strengths. It is
indicated that studies with
Our pooled estimate of 7.1% for all the first to quantify changes to ADHD
studies exceeds the 5.3% estimate prevalence estimates over time.
prevalence estimates .10% were
reported by Polanczyk et al,9 but the The included studies span 36 years
more likely to be from studies that
difference may be explained by the and report on prevalence estimates
used the DSM-IV criteria compared
with DSM-III or DSM-III-R criteria
language restriction in that sample of ADHD for .1 million children.
and by the increased number of We included all languages, and most
(x2 = 6.99, P = .03).
studies included in our review. We regions of the world were
included 83 studies published since represented. We used the most
DISCUSSION the review of Polanczyk et al was conservative estimates of prevalence
We conducted the first meta-analysis published, and we had no language by analyzing data in a manner that
investigating if there has been restriction for included studies. reflected best practice (eg, full criteria

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 benchmark. Over time and editions
of the DSM, the high-quality estimates
of prevalence are relatively
consistent. If diagnoses from national
or state population surveys exceed
our estimate, then prima facie
overdiagnosis of ADHD may be
occurring for some children. If fewer,
then underdiagnosis may be
occurring.
Prevalence estimates matter because
they have an anchoring effect.
If a condition is considered rare,
a clinician does not often consider it
as a primary diagnosis. Conversely,
if deemed common, the condition is
often considered one of the most
likely diagnoses. ADHD is a well-
known, “common” childhood
diagnosis, and publications of high
estimates receive widespread media
coverage. We have established
a benchmark prevalence estimate for
ADHD by systematically extracting
the most robust and conservative
estimates from 36 years of published
FIGURE 4 research.
Prevalence of ADHD over time. aUS Food and Drug Administration approval year. bConducted in the
United States.
There was a wide variation in
prevalence estimates between
studies, and few factors in our meta-
rather than partial criteria).14 This There are no agreed standards regression explain this variation. It is
study is also the first to rate risk of regarding accuracy or reliability of possible that how the diagnostic
bias of prevalence studies for ADHD. different informants, and studies vary criteria were applied may explain
The major limitation of our review is in their informant source. Using the some of the variation. For example,
the sampling frames of the primary most conservative estimates based on although 2 studies may consider the
studies. Few studies used a whole informant and full criteria rather than extent to which ADHD symptoms
population approach with random partial criteria may have affected clinically affect an individual, the
selection. Most were from single prevalence. Finally, only 55 studies subjective interpretation of “clinically
towns or regions, thereby limiting reported clinician involvement in the significant” can vary. This
generalizability. The majority did not diagnosis of ADHD, and studies using qualification was added to DSM-IV
discuss the potential of nonresponse these informants decreased over criteria and has been criticized for its
bias. We also did not contact time; the impact of this outcome is subjectivity.25,26 It has been changed
authors to find unpublished studies; unclear. in the Fifth Edition of the Diagnostic
given the range of prevalence and Statistical Manual of Mental
There is significant community22 and
estimates over the 3 DSM editions, Disorders to symptoms must
professional23 concern that ADHD is
however, we do not consider this “interfere with, or reduce the quality
overdiagnosed. Some researchers24
omission likely to have affected our of” functioning.6 How this change
have argued that to determine if
outcomes. affects the prevalence of ADHD is
overdiagnosis of ADHD has occurred,
unknown.
To ensure that the study data were as a comparison of actual diagnoses
homogeneous as possible, we with the prevalence estimate of
extracted prevalence estimates from a large-scale, well-conducted, national CONCLUSIONS
each by using the study’s most representative study would be Given the range of prevalence
conservative diagnosis. This method suitable. We contend that our estimates in published studies and
may also be a limitation of our review. estimates provide a suitable that these estimates matter to

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professionals and the public alike, it is 2003 and 2007. MMWR Morb Mortal Wkly 16. Skounti M, Philalithis A, Galanakis E.
clear that how the criteria of the DSM Rep. 2010;59(44):1439–1443 Variations in prevalence of attention
are applied must be standard and 6. American Psychiatric Association. deficit hyperactivity disorder worldwide.
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 Prevalence of Attention-Deficit/Hyperactivity Disorder: A Systematic Review
and Meta-analysis
Rae Thomas, Sharon Sanders, Jenny Doust, Elaine Beller and Paul Glasziou
Pediatrics 2015;135;e994
DOI: 10.1542/peds.2014-3482 originally published online March 2, 2015;

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Pediatrics is the official journal of the American Academy of Pediatrics. A monthly publication, it
has been published continuously since . Pediatrics is owned, published, and trademarked by the
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Prevalence of Attention-Deficit/Hyperactivity Disorder: A Systematic Review
and Meta-analysis
Rae Thomas, Sharon Sanders, Jenny Doust, Elaine Beller and Paul Glasziou
Pediatrics 2015;135;e994
DOI: 10.1542/peds.2014-3482 originally published online March 2, 2015;

The online version of this article, along with updated information and services, is
located on the World Wide Web at:
http://pediatrics.aappublications.org/content/135/4/e994

Pediatrics is the official journal of the American Academy of Pediatrics. A monthly publication, it
has been published continuously since . Pediatrics is owned, published, and trademarked by the
American Academy of Pediatrics, 141 Northwest Point Boulevard, Elk Grove Village, Illinois,
60007. Copyright © 2015 by the American Academy of Pediatrics. All rights reserved. Print
ISSN: .

Downloaded from http://pediatrics.aappublications.org/ by guest on May 2, 2018