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Malhi and Singhi(1) have studied
Attention Deficit Hyperactivity Disorder (ADHD). This study is a useful
addition to the inadequate database in India and should serve as a
building block for future research. However, despite this being a ‘Brief
Report’, certain queries and issues arise which merit attention.
Firstly,
the objective of the study was to determine prevalence of ADHD in
outpatient services. However, the age group was defined as between 3 and
12 years; additionally a neurologically normal population was assessed.
As ADHD can have its manifestation prior to the age of 3 years and can
be associated with neurological impairment and mental subnormality, it
could be possible that the prevalence rate and spectrum of ADHD
exhibited in the study may not be truly representative of the actual
disorder. This aspect can be viewed as a limitation to the
generalizability of results. Secondly, children were referred to
the psychology services for evaluation (Page 1256, Column 2, Para 3).
Was the need for psychosocial evaluation determined independently by the
clinician or was it based upon reporting by the parents of the children?
This could be important in determining the sensitivity of the parents
towards identifying problems arising out of ADHD. In this aspect, it
would be worthwhile to present data on the reason(s) for attendance of
Pediatrics Outpatient Department by parents of children with ADHD, i.e.,
was the attendance arising out of problems related to, or
independent from, ADHD. It will also be pertinent to mention here that
the research report does not allude to, in detail, about the utility of
Connor’s Parent Rating Scale and Connor’s Teachers Rating Scale in
confirma-tion of diagnosis of ADHD; as reported in literature(2). Thirdly,
the prevalence rate of 8.1% for ADHD is related to psychology services
of a pediatric unit. The authors have rightly not compared this with
previous data. However, it could have been discussed that this rate may
be an underestimate of the actual prevalence due to: (a) not
being from pediatric or child psychiatry outpatient services and (b)
non applicability of specific screening for ADHD on all children by the
attending pediatricians. Fourthly, the authors have commented
upon comparability/differences of results (Table I) obtained.
However, it is not clear whether the conclusions drawn are based on any
statistical analysis. In such cases, ANOVA and Kruskal Wallis test would
be appropriate tests(3). Fifthly, the authors have discussed
reasons for age at referral for the subgroups of ADHD. Another possible
reason for the lower age of referral in cases of ADHD-Hyperactive
Impulsive (ADHD-HI) group could be the more frequent presence of
defiant, aggressive, and noisy/uncontrolled behavior(2); as endorsed by
the results of this study. In fact, the lower rate of behavioral and
peer problems in ADHD-Inattentive (ADHD-AD) group is in keeping with the
general description of ADHD-AD cases being described as ‘hypoactive’(2).
Lastly, it would be interesting to examine the relationship of
age at onset (AAO) with the subtype of ADHD. In this study(1), the mean
age at presentation of ADHD-HI was approximately 3 years less than that
for the ADHD-AD type. Hyperkinetic Conduct Disorder (HCD), though not
recognized as a separate diagnostic entity in DSM-IV, is taken as a
subtype of ADHD in ICD-10(4) nomenclature and has been studied in
detail. A recent report showed that HCD children had more impulsivity,
lower intelligence, and a younger AAO with respect to children with
conduct disorder(5). It could, therefore, be possible that the ADHD-HI
group of DSM-IV may have some similarities with the HCD group of ICD-10.
The findings of lower age of referral (and possibly lower AAO) and lower
mean IQ can be interpreted in the above mentioned manner, thereby
highlighting the heterogeneity in presentation of ADHD.
Nitin Gupta,
Assistant Professor,
Department of Psychiatry,
Postgraduate Institute of Medical Education and Research,
Chandigarh 160 012, India.
E-mail: [email protected]
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Malhi P, Singhi P.
Spectrum of attention deficit hyperactivity disorders in children
among referrals to psychology services. Indian Pediatr 2000; 37:
1256-1260.
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Sadock BJ, Sadock
V. Comprehensive Textbook of Psychiatry, Seventh Edition.
Philadelphia, Lippincott Williams and Wilkins, 2000.
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Indrayan A,
Satyanarayana L. Essentials of Biostatistics: 10. Statistical
inference from quantitative data: Comparison of means and other
locations. Indian Pediatr 2000; 37: 1210-1227.
-
World Health
Organization. The ICD-10 Classification of Mental and Behavioral
Dis-orders: Clinical Description and Diagnostic Guidelines.
Geneva, World Health Organization, 1992.
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Malhotra S, Aga VM,
Balraj, Gupta N. Comparison of conduct disorder and hyper-kinetic
conduct disorder: A retrospective study from North India. Indian J
Psychiatry 1999; 41: 111-121.
We thank Dr. Gupta for
giving us an opportunity to provide more details regarding our paper(1)
which we had submitted as an "Original Article" with many
details which had to be subsequently omitted as the paper was accepted
as a "Brief Report".
The specific point
details are as follows:
1. The aim of the study
was to assess prevalence of ADHD among 3-12 year old neurologically
normal children. We purposely included only those children with a
primary diagnosis of ADHD with no other recognizable neurological
condition wherein hyperactivity and/or inattention could be an
associated feature. This was done intentionally to obviate the
profound confounding effects of the neurological disorder on the
cognitive, academic, and social profile of the child.
Regarding the issue of
presence of hyperactivity before 3 years of age, it is important to
bear in mind that it is often difficult to establish the diagnosis of
ADHD with certainty as a number of children may be active at this age
and symptoms may be wrongly labeled as ADHD. Moreover, the diagnosis
of ADHD requires the persistence of symptoms in multiple settings for
a period of atleast 6 months before a diagnostic label can be used
which may not be practically possible before the age of 3 years. The
diagnosis of ADHD in very young children should only be provisional.
2. Children from the
OPD of the Department of Pediatrics were referred to Psychology
Services when: (i) Clincians suspected a problem and/or (ii)
parents raised concerns about child’s behavior and academic
performance. In the ‘Results’ section of the paper (p 1257) the
reasons for referral are clearly mentioned(1).
3. Regarding the
utility of the Conner’s Parents and Teachers Rating Scales for
confirmation of the diagnosis of ADHD, we wish to emphasize that ADHD
is a clinical diagnosis and is based on the clinical picture of the
child and the presence of symptoms that are chronic and persistent
across several settings and cause functional impairment in several
domains of functioning(2). There is no laboratory test or
psychological test/s that can make a definitive diagnosis of
ADHD(3,4). In this light, we have used both the Parents and Teachers
ratings on the Conner’s Scales inorder to collect information from
multiple informants in several settings and not as the sole basis of
the diagnosis.
4. The prevalence of
ADHD of 8.1% as reported in our study(1) may be an underestimation of
the actual prevalence. However, it is important to recognize that the
prevalence of ADHD has been found to vary depending on the criteria
used (DSM or ICD), the kind of sample (clinical vs.
epidemiological, psychiatric vs. pediatric) and number of
informants used (single vs. multiple)(5). In fact, prevalence
of ADHD has been found to range from 1% to 23%(5). Moreover, the
prevalence reported is indeed among referrals to Psychology Services
from the entire out-patient section of the Department of Pediatric and
not from the Pediatric Unit as mentioned in the letter.
5. Since the number of
cases in each of the three groups of ADHD types were small, we were
more interested in highlighting trends rather than establishing
statistical significances. Moreover, neither the para-metric test,
ANOVA, nor the non-parametric test, kruskal Wallis, are appro-priate
for testing statistical significance between groups when the data are
in form of percentages (which is the case in our study).
6. There are several
possible explanation for the relatively younger age of the ADHD-HI
type as compared to the other two types of ADHD. We offered one for
the sake of brevity that younger children who qualify for the ADHD-II
type do no exhibit levels of inattention because they are in preschool
and attention deficits do not become apparent till a later age
(p1258). Dr. Gupta argues that the frequent presence of externalizing
behavoral difficulties in ADHD-HI children may account for their
earlier recognition. Yet another explana-tion could be that older ADHD
children may not meet criteria for the HI type as they now meet
criteria for the Combined type and/or older children may outgrow their
hyperactive symptoms. It is important to bear in mind that many
explanations can be put forward to explain a particular finding and
each may be plausible.
7. Lastly, the
Hyperactive Conduct Disordcer (HCD), a sub type of hyperactive
disorder (HKD) in ICD-10 is more similar to the ADHD-Combined type of
the DSM IV rather than the ADHD-HI(5).
Prahbhjot Malhi,
Pratibha Singhi,
Department of
Pediatrics,
Postgraduate Institute of Medical Education and Research,
Chandigarh 160 012, India.
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Malhi P, Singhi P.
Spectrum of attention deficit hyperactivity disorder in children
among referrals to psychology services. Indian Pediatr 2000; 37:
1258-1260.
-
American
Psychiatric Association. Diagnostic and Statistical Manual of
Mental Disorders. 4th edn. (DSMIV). Washington DC, American
Psychiatric Association, 1993; pp 63-65.
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Rostain AL.
Attention deficit disorder in children and adolescents. Pediatr
Clin North Am 1991; 38: 607-635.
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Cantwell DP.
Attention deficit disorder: A review of past 10 years. J Am Acad
Adol Psychiatry 1996; 35. 978-987.
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Swanson JM,
Sergeant JA, Taylor E, Sonugu-Barke ETS. Jensen PS, Cantwell DP.
Attention deficit hyperactivity disorder and hyperkinetic
disorder. Lancet 1998; 351: 429-433.
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