Ann Ist Super Sanità 2014 | Vol. 50, No. 1: 77-89
77
Maria Luisa Lorusso(a), Mirta Vernice(b), Marina Dieterich(c), Daniela Brizzolara(d), Enrica
Mariani(e), Salvatore De Masi(f), Franca D’Angelo(g), Eleonora Lacorte(g) and Alfonso Mele(g)
(a)
Servizio di Neuropsicologia dei Disturbi di Apprendimento, IRCCS E. Medea, Associazione
“La Nostra Famiglia”, Bosisio Parini, Lecco, Italy
(b)
Facoltà di Psicologia, Università degli Studi di Milano-Bicocca, Milan, Italy
(c)
II Servizio di Psichiatria, ULSS 20, Verona, Italy
(d)
Dipartimento di Medicina della Procreazione e dell’Età Evolutiva, Università degli Studi di Pisa, Italy
(e)
Società Scientiica Logopedisti Italiani
(f)
Ospedale Pediatrico Meyer, Florence, Italy
(g)
Centro Nazionale di Epidemiologia, Sorveglianza e Promozione della Salute,
Istituto Superiore di Sanità, Rome, Italy
Abstract
A Consensus Conference on Speciic Learning Disorders has been promoted by the
Italian National Institute of Health (Istituto Superiore di Sanità, ISS). The Consensus
Conference consisted in a systematic review of the international literature addressing the
issues of diagnosis, risk factors and prognosis, treatment, service delivery and organizational
models for Speciic Learning Disorders (reading, spelling/writing, calculation). Selected
papers were examined by a group of Evaluators and then discussed by a Scientiic and
Technical Committee, whose conclusions were examined and approved by a Jury Panel.
The part on diagnostic issues is presented here, encompassing a systematic discussion of
the use and appropriateness of diagnostic criteria, parameters, tasks and psychometric
indexes as illustrated in the literature, and providing recommendations for clinical
practice. Special attention has been devoted to the collection, analysis and discussion of
published data concerning languages with transparent orthography. Controversial issues
such as discrepancy criteria, role of reading comprehension and importance of accuracy
and luency are discussed.
INTRODUCTION
Although Speciic Learning Disorders (SLDs) are
one of the most common neurodevelopmental disorders
affecting children, there is still high variability in SLD
prevalence estimates, due to a lack of univocal diagnostic
criteria. Differences in prevalence data might be due to
varying deinitions of SLD, to the different methods used
for diagnosis, as well as to the different age ranges that
are considered in the various studies. In Italy, an attempt
to clearly deine diagnostic criteria for SLD was made
during the Consensus Conference promoted by the National Institute of Health (Istituto Superiore di Sanità,
Key words
• Consensus Conference
• Speciic Learning
Disorders
• diagnosis
• criteria
• parameters
ISS) and celebrated on 6-7 December 2010. The Consensus Conference aimed to ind a consensus about the
clinical conditions associated with reading, writing and
calculation disorders in school-age children. It provided
an updated, systematic and critical review of the scientiic literature on issues related to diagnostic criteria (Aquestions), risk factors and prognosis (B-questions), intervention (C-questions), organization of service delivery
(D-questions). The resulting document (retrievable from
www.snlg-iss.it./cc_disturbi_specifici_apprendimento)
was published in June, 2011, and sent as national guidelines to all diagnostic centers, clinical services, public
Address for correspondence: Maria Luisa Lorusso, IRCCS “E. Medea”, 23842 Bosisio Parini (Lecco), Italy. E-mail: marialuisa.lorusso@bp.lnf.it.
ORIGINAL
The process and criteria for
diagnosing speciic learning disorders:
indications from the Consensus
Conference promoted by the Italian
National Institute of Health
ARTICLES AND REVIEWS
DOI: 10.4415/ANN_14_01_12
ORIGINAL
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Maria Luisa Lorusso, Mirta Vernice, Marina Dieterich et al.
pediatricians and schools of the Italian territory. It is now
considered as the reference document for diagnosis and
intervention on SLD in Italy.
The present paper reports and discusses questions
and recommendations related to diagnostic issues and
processes (A-questions), which were the topics on which
some of the authors had been speciically involved as experts appointed within the Scientiic and Technical Committee (authors 1, 4 and 5) or as Evaluators (author 2).
The international disease classiication manuals used
as a reference for SLDs are:
• ICD-10 (F81 Speciic developmental disorders of
scholastic skills) [1]
• DSM IV TR (315 learning disorders) [2]
SLDs affect the skills involved in academic learning.
They include a series of medical conditions distinguished
on the basis of functional deicits:
• dyslexia, i.e., a disorder in reading (the ability to decode a text);
• dysorthography (also referred to as spelling disorder), i.e., a disorder in writing (orthographic skills and
phonographic coding);
• dysgraphia, i.e., a disorder in hand-writing (graphomotor skills);
• dyscalculia, i.e., a disorder in number and calculation skills (the ability to understand and use numbers in
computations).
In these disorders, the normal acquisition of the processes of reading, writing and calculation is affected by
an underlying neurobiological dysfunction. Additionally,
environmental factors – such as school, home, family and
social context – contribute to determine their phenotypic
expression [1, 2].
It is known that SLDs are chronic, developmental disorders, and their expression is modulated by the patient’s
age and by other environmental variables. That is, a disorder may manifest itself with different characteristics
during different developmental and educational stages.
Thus, diagnoses of SLD show a peak in primary and secondary school. In addition, the clinical expression of the
disorder depends on the orthographic complexity of the
written language. Indeed, orthographic complexity allows to differentiate between opaque languages – such as
English, characterized by a complex relationship between
graphemes and phonemes – and transparent languages
– such as Italian, characterized by a direct and predictable relationship between phonemes and graphemes. The
orthographic complexity of a language has an impact on
the processes activated for reading and writing, and consequently on the instruments that are used for assessment
and intervention. Therefore, scientiic evidence collected
on English-speaking subjects cannot be directly extended
to transparent languages such as Italian [3].
The diagnosis of SLD cannot be formulated in the irst
stages of reading and writing acquisition, since enough
time should be allowed for the teaching and learning processes to be completed. Thus, dyslexia and dysorthography are typically diagnosed from the end of the second
grade, and dyscalculia from the end of the third grade.
Indeed, anticipation of the diagnosis would increase the
risk of false positives. Nonetheless, it is possible to identify early (personal and social) risk indicators of learning
disorders that can enable early intervention and timely
diagnosis [3].
Co-morbidity of SLD with other disorders is frequent,
both with other neuropsychological dysfunctions (such
as ADHD, i.e., Attention Deicit and Hyperactivity Disorder) and with psychopathological disorders (anxiety,
depression and conduct disorder) [1, 2].
In the Italian language, SLD prevalence ranges between 2.5 and 3.5% of school-age population, as estimated by a national epidemiological study currently in
progress. Children with SLD represent about 30% of
school-age patients diagnosed at Child psychiatry services, and about 50% of patients receiving intervention.
However, SLDs are probably often underdiagnosed and/
or confused with other disorders [3].
SLDs have a major impact on both the individual
(lowering academic achievements and even causing a
premature dropout of school) and the social level (limiting social and individual expression). Scientiic evidence
highlights that only timely interventions can improve
academic performance (a measure of adaptive functioning in children). In fact, early and timely intervention is
regarded in the literature as a positive prognostic factor.
To this aim, professionals and institutions are collaborating in order to disentangle the symptomatic conditions
of SLD at various stages of development. In addition,
pediatricians must take into account the risk factors reported in the medical records, and the school dificulties
reported by families. Teachers should be able to identify
children with persistent dificulties in learning and report
the problems to the families, directing them to the appropriate health services for clinical evaluation. Child
Psychiatry Services provide evaluation and diagnosis,
and ensure appropriate support for those patients who
meet the diagnosis of SLD.
The implementation of shared clinical practice for diagnosis, involving the use of assessment protocols based
on standardized tests, as well as a scientiically based rehabilitation programs, would allow to make intervention
more effective. It would also promote a process of systematic research on the effectiveness of therapeutic interventions in the Italian-speaking population. The use of
evidence-based diagnostic criteria may also help distinguish SLD from other non-speciic school achievement
problems, usually related to familial, environmental and
cultural factors or to cognitive, neurological, sensory or
motor deicits.
This Consensus Conference was held soon after the
enactment of Law No. 170, 8 October 2010 (relating
to SLD in school) [4] that deined the rights and the
actions necessary for the promotion of SLD patients.
Therefore, the clinical recommendations proposed by
this Consensus Conference, held in Rome on the 6th and
7th December 2010, are generated in a social and cultural context full of initiatives and open debate. Close to
the publication of the document, a group of representatives of various associations and institutions involved in
SLD diagnosis and management (neuropsychiatrists,
psychologists, speech therapists, special education and
regular education specialists, geneticians, audiologists,
ophthalmologists and optometrists, etc., some of which
were among the promoters of the Consensus Confer-
METHODS
The Consensus Conference was conducted according
to the standards deined by the Consensus Program Development of the National Institutes of Health (NIH),
US. The methodology is described in the methodological manual “How to organize a Consensus Conference”
(The National Guidelines System) [6].
Organization (people involved and their tasks)
The promotion and organization of the Consensus
Conference involves different subjects, whose tasks are
briely described below.
a) The Organizing Committee – composed of representatives of the Istituto Superiore di Sanità (ISS,
National Institute of Health), independent experts
and representatives of associations of families – was
involved in:
•
promoting the conference;
•
arranging the various stages of the conference;
•
identifying the members of the Scientiic and Technical Committee;
•
identifying the members of the Jury Panel;
•
formulating, in accordance with the Scientiic and
Technical Committee, the questions for the Jury
Panel;
•
providing guidance and methodological support to
the experts for the preparation of the drafts to be
submitted to the Jury Panel.
b) The Scientiic and Technical Committee was composed of members with recognized competence
in the ield of SLDs (including child psychiatrists,
psychiatrists, neurologists, psychologists and speech
therapists). All of them were identiied by the ISS
promoters, based on their academic and/or clinical
positions and on their experience with multidisciplinary work, and invited by the Organizing Committee. Their tasks included:
•
formulating, in accordance with the Organizing
Committee, the questions to be submitted to the
Jury Panel;
•
appointing experts who were in charge of drawing
reports on individual questions to be submitted to
the Jury Panel and orally presented and discussed
during the Consensus Conference.
c) The Jury Panel was selected by the Organizing Committee in order to ensure the necessary multidisciplinary and multi-professional approach in the evaluation of the recommendations; it was composed of
16 members identiied on the basis of intellectual
autonomy, authority in science, representativeness
and high cultural and moral character, and was in
charge of:
•
signing a document specifying the procedures to be
applied within the panel;
•
reading the reports prepared by the experts;
•
attending the presentation and the discussion of reports during the Consensus Conference;
•
discussing, revising and approving the document to
be presented before the closing of the conference;
•
drawing up and approving the inal version of the
consensus document.
Within the Jury Panel, the writing committee was in
charge of preparing the inal consensus document, revising the recommendations of the preliminary document
and adding further commentaries.
The experts considered the following issues:
•
evaluation of the diagnostic procedures currently in
use (A-questions);
•
epidemiological classiication of SLD (risk factors
and prognosis), classiication of a set of tools for the
identiication of subjects at risk for SLD and tools
for intervention (B-questions);
•
effectiveness of currently available rehabilitation interventions (C-questions);
•
organizational models and service delivery (D-questions).
The current paper, as stated in the Introduction, describes how the Consensus Conference addressed issues
related to the diagnostic process (A-questions).
The literature review was surveyed by the experts of
the Documentation Department of the ISS. A panel of
evaluators reviewed the selected studies with respect to
a range of aspects (e.g., methodology, results, etc.) and
prepared grids and tables for each study, including speciic details about the clinical questions and the study design. The experts evaluated and summarized the scientific evidence available for each topic in a series of scientiic
reports (retrievable at www.snlg-iss.it/cms/iles/Allegato_
CC_DSA.pdf.). The reports were then passed to other
experts in order to allow a process of internal peer review
before inal delivery to the Jury about a month before
the conference took place. Finally, they were submitted
to public discussion. The Conference coordinators surveyed the preparation of materials and the circulation of
the drafts; the Secretariat’s Organization coordinated the
logistic and operational aspects of the conference.
To facilitate the work of experts and ensure uniformity
in the presentation of scientiic evidence on the various
topics, the ISS systematically reviewed the literature for
each of the areas covered in the conference. The scientiic literature was surveyed on a number of query databases such as PubMed, Embase, Cochrane Database of
Systematic Reviews and PsycINFO. The key terms entered in the search strategy were: ((Learning Disorders)
ORIGINAL
ence presented here) published a further document, retrievable from www.lineeguidadsa.it, aiming to collect,
discuss and substantiate the clinical protocols commonly
used at a national level and trying to converge on shared
“good practice” lines. This document answers a different
series of questions concerning diagnostic issues for SLDs
and provides practical indications about the processes
and instruments that are relevant to their assessment
and management, originating from the analysis of clinical materials and protocols, and thus fruitfully integrates
and complements the more rigorous, evidence-based indications of the ISS document.
The following section of this paper will present the methodology. Then, the speciic questions and subquestions
(here deined as “Focuses”), the analysis of the relevant
literature, the conclusions and the Recommendations of
the Consensus Conference will be detailed. To facilitate
reading, the Recommendations concerning each Question and Focus will be presented in the form of Tables.
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Maria Luisa Lorusso, Mirta Vernice, Marina Dieterich et al.
OR Dyslexia OR Reading OR Writing OR Mathematics)
NOT ((Dyslexia, Acquired) OR (Alexia, Pure)). Studies
on acquired dyslexia were excluded. Only studies published in English and Italian between January 1990 and
March 2010 and involving individuals aged less than 44
years were included. The strategies and the database are
available on the National Guidelines System website
(www.snlg-iss.it./cc_disturbi_speciici_apprendimento).
The Organizing Committee provided experts and evaluators with detailed methodological indications about
how to select the sources to be included in the bibliography. In addition the evaluators were asked to ill-out
special grids with information about methodology and
results of the selected studies, to facilitate the experts in
their analysis. Scientiic studies were included according
to the following criteria:
• systematic reviews with or without meta-analyses and
experimental studies (i.e., case reports, case series, nonsystematic reviews, experts’ opinions were excluded);
• in case of multiple systematic reviews on the same
topic, only the most recent one was considered;
• in case of multiple reviews on the same topic, only
those showing the greatest methodological validity and
internal consistency were considered;
• the studies had to show good internal validity (appropriateness of the study design, statistical analysis, and
results presentation), adequacy of the sample size and
transferability of the results to the SLD population.
A total of 42 studies were inally considered in order to
answer the Questions addressed in point A.
RESULTS AND RECOMMENDATIONS
The list of questions, and speciic focuses that will be
addressed in the present paper is:
A1 Question. What are the diagnostic criteria for
the diagnosis of SLD (in reading, spelling, calculation)?
Focus 1. The discrepancy between reading achievement and IQ
Focus 2. Cut-offs and scores
A2 Question. Which are the parameters (accuracy and reading luency, etc.) to be used in the
assessment of reading, spelling and mathematical
abilities for the diagnosis of SLD?
Focus 1. Role of reading comprehension
Focus 2. Accuracy vs luency
A3 Question. Which types of psychometric tests
and which indexes should be used to assess reading, spelling and calculation disorders?
Focus 1. Types of tests
The results of the literature review, the experts’ commentaries and the recommendations for clinical practice
will be presented for each question and focus.
A1 Question. What are the diagnostic criteria
for the diagnosis of SLD (in reading, spelling,
calculation)?
Premise
According to the ICD-10 and the DSM-IV TR diagnostic manuals, used by the Italian Health System, a
series of conditions must be met in order to formulate
a diagnosis of Speciic Learning Disability (see Appendix 1 and 2). It is interesting to note that the ICD-10
and the DSM-IV TR diverge with respect to the deinition and the diagnosis of Speciic Spelling Disorders. In
fact, whereas the ICD-10 recognizes the existence of a
developmental disorder of written expression speciic to
spelling, according to the DSM-IV TR a “Disorder of
Written Expression” can be diagnosed only when dificulties in written expression go beyond poor or illegible
handwriting and poor spelling, and extend to sentence
and discourse construction. In addition, under the ICD10 classiication, in contrast to the DSM-IV TR, the
co-occurrence of a reading disorder is considered as an
exclusion criterion for the diagnosis of “Speciic Spelling Disorder”. In other words, ICD-10 considers reading
and spelling disorders as two aspects of the same problem, while DSM-IV TR underscores the differences between the two, at the same time broadening the concept
of writing disorder beyond spelling dificulties.1
The diagnostic criteria for the “Speciic Disorder of
Arithmetical Skills” in the ICD-10 establish that skills
assessed with standardized tests must fall outside the
limits of 2 standard deviations (SD) “from the level expected based on the child’s chronological age and on his
overall intellectual level”. However, these criteria do not
specify any parameter (e.g., luency, accuracy) nor any
speciic skill to be considered for evaluation (e.g., mental numerical computation, etc.). Additionally, in order
to make a diagnosis, the absence of “a history of either
signiicant dificulties in spelling and reading” must be
ascertained, and scores in both these areas have to be
within the normal range (within 2 SD). That is, the diagnosis is excluded in cases of “dificulties associated
with a reading or spelling disorder”. In this case, the
most frequently encountered in clinical practice, it will
be necessary to make a diagnosis of “Mixed Disorder of
Scholastic Skills”. The DSM-IV TR provides indications
similar to the ones given for the other disorders and does
not specify which parameters and which skills should be
taken into consideration for the diagnosis.
In addition to the differences between the two diagnostic manuals described thus far, the application of diagnostic criteria under both manuals raises a number of
issues that will be highlighted and discussed in the next
section.
Focus 1. The discrepancy between reading achievement and
IQ (discrepancy criterion)
According to the DSM-IV TR and ICD-10, learning
disorders are deined with respect to a discrepancy criterion, that is, the level of performance in tests of reading,
writing or calculation must be signiicantly lower than
expected, based on education and intellectual level. The
discrepancy criterion has been historically interpreted in
several ways. The two main approaches to the discrepancy criterion are reported below:
a) calculating the standard values for both the intellectual level and school performance, and requiring that
the difference between the two values exceeds the limit
1. In the inal version of DSM-5, the problem of distinguishing between
reading and spelling disorders is partially overcome by the inclusion of all
“symptoms” in a single diagnostic category, although use of more detailed
speciiers is recommended. Nonetheless, extension of writing disorders
beyond simple spelling errors is preserved and further emphasized.
Reading
A number of studies [6, 7] observed that discrepant
children (i.e., children showing a signiicant discrepancy between their IQ and their reading performance)
did differ from non-discrepant ones with respect to
cognitive abilities as expected (Verbal, Performance
and full-scale IQs, syntax and vocabulary tests), but
their performance overlapped in tests of phonological
awareness, rapid naming and verbal memory. Addi-
tionally, there were no differences between the two
groups in reading comprehension, mathematical
concepts, spelling and writing. A longitudinal study
[8] further indicated that non-discrepant children
showed an overall better performance in a range of
standardized tests than the discrepant ones in the
second, but not in the ifth grade. A study employing cluster-analysis indicated that various subgroups
of children with varying degrees of reading abilities
could be identiied based on their neuropsychological proiles, but these subgroups did not differ in IQ
[9]. Taken together, these studies suggest that an accurate description of cognitive proiles is more useful
to inform diagnosis than IQ is2.
Studies conducted in orthographically transparent
languages led to similar results. Jiménez and Rodrigo
[10] observed that performance on a lexical decision
task was a more critical factor than IQ scores in order
to discriminate between a group of Spanish-speaking
children with SLD and age-matched controls. In Swedish, a language with a moderately transparent spelling,
Svensson and Jacobson [11] showed that the inclusion
of IQ as a diagnostic criterion led to a lower stability
in the diagnosis of SLD between 9 and 19 years of age.
Rispens et al. [12] further observed that inclusion of
discrepancy as a diagnostic criterion had little effects
on the number of children (irst and second grade of
primary school) diagnosed with a learning disorder: excluding IQ from the model, the number of diagnoses
increased by 0.2-0.5% (depending on the reading test
used). The lowering of the cut-off on IQ from 85 to 80,
by contrast, had a greater impact, increasing diagnoses
by 1,3-1,5%. Giovingo et al. [13], on the other hand,
showed that use of IQ-discrepancy criteria applied to
a group of students with school dificulties leads to a
signiicantly lower number of diagnoses (24-29% of
the sample) if compared with two other methods, one
based on intra-individual discrepancy with respect to
other performances, the other corresponding to an
underachievement criterion, with an absolute cut-off
(16th percentile) on performance (diagnosis rates of
40 to 65%).
Questioning the usefulness of IQ scores to predict
response to treatment, Stage et al. [14] showed that
Verbal IQ did indeed predict reading improvement
after an intervention program on word and non-word
reading, but its predictive power was weaker than that
of phonology, rapid naming and attention tests.
Further problems concern the statistical properties
(reliability, stability) of the assessment results (see [15]
for a detailed discussion). First, the correlation between IQ scores and reading and writing skills is weak
[16], decreases considerably from 8-9 years of age to
10-12 years [17] and is much lower than that found
in the normal population (but see [18] for a different view). The speciic test used to assess IQ seems to
2. A recent neuroimaging study by Tanaka et al. (2011) published in Psychological Science (http://pss.sagepub.com/content/early/2011/10/17/0956797611419521) conirms the absence of any signiicant difference between discrepant and nondiscrepant poor readers
also with regard to cortical activation patterns during dyslexia-related
phonological processing tasks.
ORIGINAL
of 1 or 2 SD (a mathematically more sophisticated approach but almost never used in Europe is a regression
analysis that includes as a factor the correlation between
IQ scores and reading skills);
b) setting the cut-off for both school performance
(normally not above the maximum level of -1, -1.5, or
-2 standard deviations below the mean or the 10th or
5th percentile with respect to age and education) and
intellectual level (usually not below the minimum level
of 85 IQ points).
Alternative solutions proposed in the literature can be
considered variants of these two original approaches.
It is important to examine in detail the implications
of these two positions. The irst approach allows luctuation of performance scores: the diagnosis of SLD
can be made also when the performance on standardized tests is not below age mean, provided IQ is particularly high. Alternatively, it allows to diagnose SLD
when IQ is lower than 85, provided performance on
standardized tests is suficiently discrepant. Clearly,
this approach is based on the assumption that academic ability can be predicted on the basis of intelligence. In fact, the correlations reported in the literature between IQ scores and reading skills are rather
low, ranging between 0.6 and 0.75. A mathematical
procedure to calculate “expected performance” on the
basis of IQ was applied in the American context, with
controversial results, but no such formulas have been
made available for languages such as Italian.
The second approach is the most frequently adopted
in the European countries and does not require to deine the exact relationship between IQ and academic
skills. Nonetheless, excluding from the diagnosis subjects with an IQ below 85, even in the presence of very
low levels of performance, implies that low performance
in these cases is assumed to be of a different nature
than in the case of subjects with IQ in the normal range
(excluding mental retardation, the problem arises for
children with IQs between 70 and 85, the so-called
“borderline” cases). Thus, although less explicitly, this
position also rests on the assumption that a low IQ
score per se can explain poor performance in reading,
writing and computing. It would be possible, therefore,
to hypothesize a substantial difference between two
types of “poor readers”: those showing a signiicant discrepancy between their IQ level and their performance,
and those exhibiting a low but non-discrepant performance. Several studies have been conducted to explore
the validity of this hypothesis. An analysis of these studies is reported in the following sections, subdivided according to the speciic type of SLD (reading, spelling/
writing, number and calculation skills).
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play a determinant role in producing these contrasting
results. A second issue refers to the stability and reliability of the IQ measures. Ingesson [19] showed that
full-scale IQ remained substantially stable over time
as a result of a progressive decrease in Verbal IQ and
increase in Performance IQ along with age. A third
problem relates to the use of cognitive tests which may
be inluenced by the presence of language or reading
disorders (language disorders may for instance inluence comprehension of instructions or prevent the use
of an inner guide during performance, while reading
disabilities may prevent the acquisition of information
from textbooks etc.). Such interferences might lead to
underestimate the child’s cognitive potential [20, 21].
Lowering of IQ scores due to progressive decrease in
motivation as a consequence of the learning disorder,
known as “Matthew effect” is a further possibility that
should be taken into account (see [19], but also [18]
for a contrasting view).
Spelling and writing
As for spelling disorders, data from the literature
predominantly relate to English (for the Italian language, see [22, 23]) and involve populations of children who meet the diagnosis of dyslexia, but not of
speciic spelling disorder according to ICD-10. This
may relect the fact that spelling disorders are usually
considered to be associated with reading disorders: indeed, many neuropsychological functions are involved
in both reading and writing. In the description of participants’ characteristics, the criterion of discrepancy
between writing/spelling achievement and IQ scores
is not directly mentioned. As a result, data and conclusions of the existing studies on spelling disorders
cannot be disentangled from the characteristics of dyslexia and considered speciic to spelling/writing disorders per se.
Number and calculation skills
The problem of variable diagnostic criteria applies
also to the speciic disorder of arithmetical skills, so
that it is dificult to compare research data. There are,
nonetheless, some particularly critical issues that have
been more systematically addressed in the international literature and that will be illustrated in greater
detail. These issues include a) the validity of discrepancy-criteria as compared to cut-offs on performance;
b) the relevance of criteria based on the speciic type
of dificulty as compared to performance level in general and c) the expression of the disorder over time.
a) The irst question has been addressed in a study
[24] comparing the results of the application of traditional discrepancy (between IQ and performance) criteria versus a cut-off on performance only. The authors
underscore that mathematical dificulties are not simply the expression of low intellectual functioning (see
also [25, 26]), and conclude that the second approach
is more valid than the former one. The generalizability of the conclusions is limited, though, by the inclusion, in all the mentioned studies, of children with IQs
above 80 only.
b) As to the question of the informativeness of the
speciic dificulties manifested by the children, a meta-analysis [27] suggested that criteria based on the
speciic type of dificulty, e.g., in number facts [28] or
number processing [26] are particularly meaningful.
c) A further important criterion seems to be the
persistence of the disorder over years [24, 27, 29-31].
Indeed, after primary school, subjects with a disorder
of arithmetical skills keep showing dificulties in solving simple tasks [29]. In particular, the most stable
deicit concerns the recovery of arithmetic facts, while
procedural dificulties improve more frequently [30].
Among other studies, Mazzocco et al. [29] observed
that children with Mathematical Learning Disabilities (MLD, performing below the 10th percentile on
standardized mathematical tests) improved their performance at a slower pace as compared not only to
controls (typical achievers, TA), but crucially to low
achievers (LA, performing between the 11th and the
25th percentile) as well (MLD <LA <TA). Thus, low
achievers (LA), but not dyscalculic children (MLD),
tended to reduce their lag with respect to controls
(TA) over time.
Conclusions
With respect to the discrepancy criterion reported in
the diagnostic manuals, it is a common clinical practice to make a diagnosis of SLD only in the presence of
IQ scores higher than or equal to 85. However, the use
of this criterion is controversial on the basis of:
a) empirical research over the last 20 years, showing
that: 1) there are no substantial differences between
discrepant and non-discrepant children in neuropsychological proiles (except for obvious differences in
intellectual skills), or in response to treatment; 2) the
diagnosis based on the discrepancy criterion appears
to be less reliable and less stable over time, depending
on the nature and on the type of tests used;
b) the new diagnostic trends, which tend to reduce
the role of IQ scores. The new edition of DSM, DSM5 (see Appendix 3, 4 and 5), is going to modify Criterion A in a substantial way, with direct reference to
IDEA regulations (2004) [32] in the US which state
that: “the criteria adopted by the State must not require the use of a severe discrepancy between intellectual ability and achievement for determining whether
a child has a speciic learning disability, as deined in
34 CFR 300.8(c)(10)”.
Note that similar considerations apply to the diagnosis of Dysorthography/Spelling disorders, although
there are no studies to our knowledge which have
addressed the problem of different characteristics in
samples of dysorthographic children with different levels of intellectual ability3.
3. In one of the irst studies taking into account the effects of intelligence scores on spelling ability, Finucci and colleagues (see Brain
and Language 1983, 20(2), 340-355) found no relationship between
spelling performance and IQ in reading-disabled children, but no IQs
lower than 95 were included in the sample; a recent follow-up study on
mid-age adults with former diagnoses of reading and spelling disorders,
allowing greater variation of IQ scores (above 70) conirms the absence
of IQ effects on spelling in spelling-disordered individuals (Maughan
et al., 2009, published in Journal of Child Psychology and Psychiatry
50.8:893-901).
Recommendations
A1.1 A more lexible consideration of the criterion of a discrepancy between performance and IQ is recommended
when diagnosing SLDs.
A1.2 Use of multicomponential tests for intellectual assessment is recommended in the presence of borderline
IQ (70-85) levels, when diagnosing SLDs, since the cognitive proile is more informative than the mere IQ scores.
A1.3 When diagnosing SLDs, it is rather recommended to
emphasize the discrepancy with respect to expected performance according to the subject educational level.
Focus 2. Cut-offs and scores
In order to identify poor performance on academic
tests, that might be of clinical interest, the diagnostic
manual ICD-10 indicates a cut-off of -2 SD (or the 5 th
percentile) below the mean. However, in the literature
on dyslexia cut-off levels are often much higher (the
25th or the 15th percentile are often referred to).
As for dyscalculia, the cut-offs reported in the literature are also very variable, ranging from the 5th
percentile [31] to the 46th [33], and so are the various tests used to measure arithmetic skills (as a result,
reported prevalence is also not uniform: Ramaa and
Gowramma [34] address this issue and suggest a igure of about 5%). Recent studies suggest to consider
as dyscalculic only children whose performance falls
below the 10th percentile in at least two speciic tests
of basic arithmetic skills, whereas Low Achievers (LA)
perform between the 11th and 25th percentile, and
Typical Achievers (TA) perform above the 25th percentile [24, 29, 30].
A1 Question. What are the diagnostic criteria for the
diagnosis of SLD (in reading, spelling, calculation)?
Focus 2. Cut-offs and scores
Recommendations
A1.4 In the absence of clear indications from the literature
on the use of speciic cut-offs in the assessment of academic skills for the diagnosis of SLDs, the application of
the cut-offs suggested by the diagnostic manual ICD-10
should be recommended.
A1.5 The use of standard deviations (especially for speed
scores, more symmetrically distributed) and percentiles
(especially for accuracy or error scores, characterized by
asymmetric distributions) according to available norms is
recommended, since the distributional properties of these
scores ensure better precision in measuring performance
than grade-equivalent scores. In fact, the function describing change in performance according to school grade is
too far from linear to allow calculation of meaningful and
comparable measures of achievement or backwardness
(e.g., a 3-years lag at primary school has a very different
meaning if compared with a 3-years lag at college).
A2 Question. Which are the parameters (accuracy and reading luency, etc.) to be used in the
assessment of reading, spelling and mathematical
abilities for the diagnosis of SLD?
Focus 1. Role of reading comprehension
The diagnostic manuals ICD-10 and DSM-IV include reading comprehension in addition to the parameters of accuracy and luency. However, in accordance with the latest scientiic evidence, performance
in reading comprehension is rarely considered in the
clinical practice in countries with orthographically
transparent languages, such as Italy, and, more recently, also in Anglophone countries. These issues had
been given special emphasis in the proposed revisions
of DSM-IV as retrieved from the APA site in November 2010 (see Appendix 4)4. It is clear, indeed, that
problems in comprehension are not closely related to
dificulties in decoding (which underlie the process of
reading and writing), and cannot be viewed as simple consequences of their presence. In the typically
developing population, the relationship between reading and comprehension decreases with schooling (as
described in the model “simple view of reading” by
Gough and Tunmer [35]), indicating that as the decoding process becomes more automatized, its ability
to predict reading comprehension weakens [36-38].
For instance, Nation and Snowling [39] analyzed
intercorrelations of performance on a set of reading,
reading comprehension, sentence completion and listening comprehension tests, in a sample of 184 children
aged 7 to 9, also including 17 children with oral comprehension dificulties. All tests turned out to be highly
intercorrelated, except for the listening comprehension
and the non-word reading test. Similarly, Snyder and
Downey [40] reported that in 8-11 years old children
with reading disorders, reading comprehension was
predicted by accuracy in sentence completion and lexical retrieval tasks, whereas for 11-14 years-old children,
inferential skills (the ability to integrate missing information) are better predictors. Again, Nation et al. [38]
observed that poor comprehenders scored signiicantly
lower than controls in syntactic awareness, listening
comprehension and expressive vocabulary tasks, but
not in phonological and meta-phonological tasks.
Conclusions
It seems clear that the ability to comprehend written text is at least partially independent of decoding
abilities (although it can obviously be affected by the
presence of decoding deicits) and cannot be included
among the parameters to be evaluated for the diagnosis
of Speciic Reading Disorder or Dyslexia. One possibility could be to diagnose a Disorder in Reading Comprehension without decoding deicits (some authors
propose to consider it as a linguistic disorder). Another
possibility (indicated by the proposed revisions of the
DSM-IV TR, see Appendix 4)5 is the classiication as
a Learning Disorder (super-ordinate category), without
further speciication.
4. The inal version of the DSM-5 (not available at the time of celebration of the Consensus Conference) has radically changed its perspective, and a more general category of Speciic Learning Disorders,
including comprehension and mathematical reasoning, is now being
proposed instead. Appendix 5 (text retrieved from APA site in August
2013) gives an overview of the actual recommendations of DSM-5.
5. In the inal version of DSM-5, however, comprehension dificulties
have been included in the list of deicits belonging to the category of
Speciic Learning Disorders.
ORIGINAL
A1 Question. What are the diagnostic criteria for the
diagnosis of SLD (in reading, spelling, calculation)?
Focus 1. Discrepancy criterion
ARTICLES AND REVIEWS
83
DIAGNOSING SPECIFIC LEARNING DISORDERS
84
Maria Luisa Lorusso, Mirta Vernice, Marina Dieterich et al.
ORIGINAL
ARTICLES AND REVIEWS
A2 Question. Which are the parameters (accuracy and reading luency, etc.) to be used in the assessment of reading,
spelling and mathematical abilities for the diagnosis of SLD?
Focus 1. Role of reading comprehension
Recommendations
Premise: ICD-10 criteria for diagnosis are fully maintained unless otherwise speciied, with the modiications indicated in the
recommendations in re sponse to questions A1 and A2. In particular, the exclusion of IQ scores below 70, as assessed with a
valid, standardized, individually administered test, is unmodiied.
A2.1 We recommend, for the purposes of diagnosing dyslexia,
not to include reading comprehension as a diagnostic parameter, since persons with comprehension problems but good
decoding skills do not meet the criteria for dyslexia.
A2.2 We recommend however, when diagnosing dyslexia, to keep
considering comprehension in passage-reading tests as one of the
critical tests to be used for a broader functional characterization of
the disorder (see recommendations related to the question A3).
Focus 2. Accuracy vs luency
It has been shown that, in orthographically transparent languages, luency is a more sensitive indicator of the
presence of a reading disorder as compared to accuracy,
especially after the irst years of schooling.
A number of studies conducted in orthographically
transparent languages provided evidence that luency is
a major predictor of reading dificulties as compared to
accuracy. For instance, German-speaking children with
dyslexia showed more dificulties in luency than in accuracy in word and non-word reading [41, 42]. Lehtola and
Lehto [43] showed similar results for Finnish- (a highly
transparent orthography) speaking students with dyslexia.
On the other hand, both Landerl et al. [42] and Davies et
al. [44] showed that German and Spanish children with
dyslexia, albeit being less luent and accurate than agematched controls in reading tasks, were less accurate but
equally luent when compared to reading-age controls.
As for spelling and writing, luency is usually not explicitly mentioned as a diagnostic criterion [45, 46]. Angelelli
et al. [22, 23] speciied that accuracy in writing performance had been taken as the diagnostic parameter in her
studies (which set a cut-off of -2 SD below the mean of
age-matched controls and also provide an accurate analysis of error types).
The issue of accuracy versus luency parameters has
been addressed also for the diagnosis of Dyscalculia.
Many authors consider luency a more relevant parameter as compared to accuracy [25, 47, 29], whereas others
observe that accuracy does not improve by allowing extra
time on the task [31]. A careful examination of the type of
errors is recommended, in order to provide reliable indications about the disorder, and differentiate children with
Dyscalculia from low achievers and typically developing
children. Mazzocco et al. [29] reported that low achievers
differed from typically developing children with respect to
the number of errors, but not in the type of errors. By contrast, children with dyscalculia differed from the other two
groups in both the number and the type of errors, indicating an atypical development.
Conclusions
Based on research data, it appears that in addition to
reading accuracy, reading luency is the most sensitive
parameter for the detection of reading dificulties in
orthographically transparent languages such as Italian.
As for arithmetic skills, both parameters appear to be
sensitive, whereas for spelling and writing skills, luency
has not been systematically addressed in the analyzed
literature as a diagnostic parameter.
Another important source of information for the purpose
of diagnosing disorders of writing and arithmetic skills is
the qualitative analysis of errors. In doubtful cases, in fact,
the type of errors could help differentiating between low
achievers and subjects with a speciic learning disorder.
A2 Question. Which are the parameters (accuracy and
reading luency, etc.) to be used in the assessment of
reading, spelling and mathematical abilities for the diagnosis of SLD? Focus 2. Accuracy vs luency
Recommendations
A2.3 For the diagnosis of dyslexia, it is recommended to consider reading luency in addition to the parameter of accuracy
as reported in the ICD-10 manual criterion A.
A2.4 For the diagnosis of dysorthography, it is recommended to
consider accuracy parameters in standardized tests for spelling,
as reported in the ICD-10 manual criterion A,
A2.5 For the diagnosis of dysorthography, it is recommended
to use qualitative analysis of errors as an additional source of
information that can help guiding the diagnosis and deining
functional proiles, in order to differentiate low achievers from
subjects with a speciic learning disorder.
A2.6 For the diagnosis of dyscalculia, it is recommended to
consider the parameters of both accuracy and luency in standardized tests for arithmetic skills, as reported in the ICD-10
manual criterion A.
A2.7 For the diagnosis of dyscalculia, it is recommended to
include qualitative analysis of errors as an additional source
of information that can help guiding the diagnosis especially in
doubtful cases, in order to better differentiate low achievers from
subjects with a speciic learning disorder.
A3 Question. Which types of psychometric tests
and which indexes should be used to assess reading, spelling and calculation disorders?
Focus 1. Types of tests
In the literature, as well as among assessment instruments available in the Italian language, there are different
types of reading tests, including word, non-word, sentence
and passage reading tests. Presumably, the choice of different diagnostic tests in different studies has the effect to
select different subgroups within the SLD population, with
different cognitive and performance proiles.
Interestingly, meta-analysis studies and experimental
evidence indicate that spelling and non-word reading abilities are better predictors of word reading than phonological awareness and rapid naming skills [46]. Additionally,
phonemic awareness appears to lose power over time in
predicting reading performance, while scores on linguistic
tasks such as vocabulary and naming tests appear to be
more stable predictors [48]. Additional evidence revealed
that accuracy in a non-word reading test is not predicted
by performance in a passage reading test, but rather by
word reading scores [49]. Word and non-word reading appeared to be so strongly correlated in the irst four years of
schooling, that they could be considered expressions of the
same construct [50]. In this study, phonological awareness
appears to be more correlated with word than with non-word
85
DIAGNOSING SPECIFIC LEARNING DISORDERS
Conclusions
As for reading disability, based on the literature, it appears that word and non-word reading tasks highly correlate with each other and exhibit higher reliability and
predictive value for diagnosis than passage reading tests.
Therefore, it is recommended to use both word and nonword reading tests. Non-word reading tests are especially
sensitive with dyslexic and/or compensated adults. Passage reading tests appear less reliable and more inluenced
by other abilities, however the experts highlight that text
reading may be seen as a more ecological test with respect
to the criterion of interference with daily life activities reported in the diagnostic manuals.
A3 Question. Which types of psychometric tests and
which indexes should be used to assess reading, spelling
and calculation disorders?
Focus 1. Types of tests
Recommendations
A3.1 For the diagnosis of dyslexia, it is recommended to use
word and non-word reading tests, that are highly correlated to
the disorder, and show higher reliability and predictability as
compared to whole text reading.
A3.2 For the diagnosis of dyslexia in dyslexic and/or compensated adults, use of non-word reading tests is recommended
for its relevance in this particular population.
A3.3 For the diagnosis of dyslexia, the use of a whole text
reading test (including comprehension assessment) is recommended in order to evaluate interference of the learning
disability with daily activities (as reported by the diagnostic
manual ICD 10).
A3.4 For the diagnosis of dysorthography, the use of word and
non- word dictation tests is recommended.
A3.5 For the diagnosis of dysorthography, the use of single
word and text dictation is recommended, along with the production of written texts and sentences.
A3.6 For the diagnosis of dysorthography, assessment of different components according to educational stage is recommended, as speciied below:
In early school years, assess grapheme-phoneme conversion
processes.
During primary school, assess spelling at the lexical level,
which is becoming progressively more important over time.
At the end of primary school, assess the presence of grapheme-phoneme conversion errors which, if found in this age
range (the advanced stages of primary school), constitutes a
marker of particularly severe disorders.
A3.7 For the diagnosis of dyscalculia, tests to assess speciic
skills (arithmetic facts, mastery of basic skills such as addition,
subtraction, multiplication, reading and writing numbers; comparing numerosity; counting skills) are recommended.
A3.8 For the diagnosis of dyscalculia, use of standardized
tests assessing memory and visual-spatial skills is further recommended, as these support and/or facilitate the acquisition
and consolidation of arithmetic skills.
Conlict of interest statement
There are no potential conlicts of interest or any inancial or personal relationships with other people or
organizations that could inappropriately bias conduct
and indings of this study.
Received on 9 October 2013
Accepted on 31 January 2014.
ARTICLES AND REVIEWS
dition, as some of the above-listed skills are supported by
working memory [59- 62, 47], it could be critical to assess
working memory skills too [27].
ORIGINAL
reading, while RAN (Rapid Automatic Naming) and phonological awareness were equally good predictors of word
and non-word reading. Further evidence however suggests
that improvement in word reading is strongly associated with
Verbal IQ, whereas improvement in non-word reading is best
predicted by tests of phonology, RAN and attention [14].
Evidence form studies on dyslexia in adults indicated
that subjects with a reading disorder are signiicantly slower
and less accurate in non-word than in word reading [51].
Lyytinen et al. [17] showed that phonological spelling and
orthographic word recognition abilities predicted reading
comprehension of Finnish students when they were 11
years old, with phonological tasks increasing their predictive
power with respect to text comprehension with age, compared with orthographic tasks. Svensson and Jacobson [11]
reported that a cut-off criterion of -1 SD below the norm in
non-word reading allows to identify subjects with dyslexia
at 9 and 19 years of age. A study on Malaysian-speaking
(a language with regular orthography) irst-grade children,
showed that both word and non-word reading tests (highly
correlated) strongly correlate with a spelling task, a passage
comprehension test and a meta-phonological test [52].
Miller-Shaul [53] observed that adult participants with a
reading disorder in Israel perform signiicantly poorer than
age-matched controls in phonological tasks but not in orthographic tests.
As for the type of tests used for the diagnosis of writing/
spelling disorders, most studies in the literature use dictation tests. A longitudinal study in Italian [23] indicated
that the nature of the writing dificulties involved in spelling disorders changes with age and education. Interestingly,
Italian children with Dyslexia early learn to avoid errors in
phoneme-to-grapheme conversion and syllabic conversion
tasks, while they keep making many errors on a lexical basis. Gregg et al. [54] studied the interrelationships between
phonemic awareness and orthographic awareness and their
inluence on writing skills, showing that spelling skills were
largely independent of phonological awareness and related
to the acquisition of a lexical strategy for writing.
As for dyscalculia, different criteria and tests have been
used in the literature, which is one of the reasons why experimental groups so often showed different clinical features and were not comparable. Previous studies did not
discuss the assumptions underlying the distinction between
a type of dyscalculia based on a numerical cognition deicit
and another type based on procedural deicits. Rousselle
et al. [47] observed that children with a deicit in number
skills have problems in accessing number magnitude from
symbols rather than in processing numerosity per se. Other
studies have suggested that the proile may be more impaired in the presence of comorbid reading disorders [33,
55], although Rousselle and Noël [47] did not observe any
signiicant difference between groups with and without
comorbid reading disorders. It appears therefore essential
to assess the child’s ability in a series of tasks such as: recalling number facts; applying calculation procedures [33];
reading and writing numbers; linking a number (written or
orally presented) with the appropriate quantity of tokens
[56]; processing and comparing numerosities [47]; counting [57]. It is also crucial to consider error types [58, 33, 24]
and to evaluate the persistence of immature computation
strategies (e.g., long-term use of the ingers) [33, 29]. In ad-
86
Maria Luisa Lorusso, Mirta Vernice, Marina Dieterich et al.
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ARTICLES AND REVIEWS
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Maria Luisa Lorusso, Mirta Vernice, Marina Dieterich et al.
ORIGINAL
ARTICLES AND REVIEWS
Appendix 1.
Diagnostic criteria according to ICD-10
F81 Speciic developmental disorders of scholastic skills
F81.0 Speciic reading disorder
A. Either (1) or (2):
(1) A score on reading accuracy and/or comprehension that is at least 2 standard errors of prediction below the level expected
on the basis of the child’s chronological age and general intelligence; with both reading skills and IQ assessed on an individually administered test standardized for the child’s culture and educational system.
(2) A history of serious reading dificulties, or test scores that met criteria A (1) at an earlier age, plus a score on a spelling test
that is at least 2 standard errors of prediction below the level expected on the basis of the child’s chronological age and IQ.
B. The disturbance in A signiicantly interferes with academic achievement or activities of daily living that require reading skills.
C. Not directly due to a defect in visual or hearing acuity, or to a neurological disorder.
D. School experiences within the average expectable range (i.e. there have been no extreme inadequacies in educational
experiences).
E. Most commonly used exclusion criterion: IQ below 70 on an individually administered standardized test.
F81.1 Speciic spelling disorder
A. A score on a standardized spelling test that is at least 2 standard errors of prediction below the level expected on the basis
of the child’s chronological age and general intelligence.
B. Scores on reading accuracy and comprehension, and on arithmetic, that are within the normal range (+ 2 standard deviations from the mean).
C. No history of signiicant reading dificulties.
D. School experience within the average expectable range (i.e. there have been no extreme inadequacies in educational
experiences).
E. Spelling dificulties present from the early stages of learning to spell.
F. The disturbance in A signiicantly interferes with academic achievement or activities of daily living that require spelling skills.
G. Most commonly used exclusion criterion: IQ below 70 on an individually administered standardized test.
F81.2 Speciic disorder of arithmetical skills
A. A score on a standardized arithmetic test that is at least 2 standard errors of prediction below the level expected on the
basis of the child’s chronological age and general intelligence.
B. Scores on reading accuracy and comprehension, and on spelling that are within the normal range (+ 2 standard deviations
from the mean).
C. No history of signiicant reading or spelling dificulties.
D. School experience within the average expectable range (i.e. there have been no extreme inadequacies in educational
experience).
E. Arithmetic dificulties present from the early stages of learning arithmetic.
F. The disturbance in A signiicantly interferes with academic achievement or activities of daily living that require mathematical skills.
G. Most commonly used exclusion criterion: IQ below 70 on an individually administered standardized test.
Appendix 2.
Diagnostic criteria according to DSM-IV TR
Diagnostic criteria for 315.00 Reading Disorder
A. Reading achievement, as measured by individually administered standardized tests of reading accuracy or comprehension, is substantially below that expected given the person’s chronological age, measured intelligence, and age-appropriate
education.
B. The disturbance in Criterion A signiicantly interferes with academic achievement or activities of daily living that require
reading skills.
C. If a sensory deicit is present, the reading dificulties are in excess of those usually associated with it.
Diagnostic criteria for 315.2 Disorder of Written Expression
A. Writing skills, as measured by individually administered standardized tests (or functional assessments of writing skills),
are substantially below those expected given the person’s chronological age, measured intelligence, and age-appropriate
education.
B. The disturbance in Criterion A signiicantly interferes with academic achievement or activities of daily living that require
the composition of written texts (e.g., writing grammatically correct sentences and organized paragraphs).
C. If a sensory deicit is present, the dificulties in writing skills are in excess of those usually associated with it.
Diagnostic criteria for 315.1 Mathematics Disorder
A. Mathematical ability, as measured by individually administered standardized tests, is substantially below that expected
given the person’s chronological age, measured intelligence, and age-appropriate education.
B. The disturbance in Criterion A signiicantly interferes with academic achievement or activities of daily living that require.
mathematical ability.
C. If a sensory deicit is present, the dificulties in mathematical ability are in excess of those usually associated with it.
Appendix 3.
Proposed revisions for DSM-5 retrieved from APA site, 22 November 2010 (NB subsequently revised and changed)
(www.dsm5.org/ProposedRevisions/Pages/proposedrevision.aspx?rid=84#) speciically relating to the discrepancy criterion.
Proposed new criteria
Dyslexia
Appendix 4.
Proposed revisions for DSM-5 retrieved from APA site, 22 November 2010 (NB subsequently revised and changed)
(www.dsm5.org/ProposedRevisions/Pages/proposedrevision.aspx?rid=85#) speciically relating to the parameters to be considered
Proposed new criteria
Dyslexia
A. Dificulties in accuracy or luency of reading that are not consistent with the person’s chronological age, educational opportunities, or intellectual abilities.
Multiple sources of information are to be used to assess reading, one of which must be an individually administered, culturally appropriate, and psychometrically sound standardized measure of reading and reading-related abilities.
B. The disturbance in criterion A, without accommodations, signiicantly interferes with academic achievement or activities
of daily living that require these reading skills.
Rationale
• (…)
• Reading luency is included as a critical feature of reading acquisition: poor luency is a key feature of dyslexia in adulthood;
also poor luency is a key feature of dyslexia in languages other than English (e.g., Bashir & Hook, 2009 Lang Speach Hear
Services Sch; Share DL, 2008 Psychol Bull; Shaywitz, SE et al. 2008 Annu Rev Psychol; Shaywitz et al. Biol Psychiatry 2003).
• Recommend that reading comprehension per se be omitted from DSM-5, because individuals who have speciic reading
comprehension problems in the presence of good decoding skills, do not meet criteria for dyslexia. Such individuals typically
are found to have poor oral language (as in communication disorders). However, speciic reading comprehension disorders
could be coded under the newly proposed superordinate category of Learning Disability.
• (…)
Appendix 5.
“Speciic Learning Disorder Fact Sheet” – inal version of DSM-5 (retrieved from APA site, 2 august 2013) (www.dsm5.
org/Documents/Speciic Learning Disorder Fact Sheet.pdf) concerning “A 08: Speciic Learning Disorder”
The upcoming ifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) takes a different approach
to learning disorders than previous editions of the manual by broadening the category to increase diagnostic accuracy and effectively target care. Speciic learning disorder is now a single, overall diagnosis, incorporating deicits that impact academic
achievement. Rather than limiting learning disorders to diagnoses particular to reading, mathematics and written expression,
the criteria describe shortcomings in general academic skills and provide detailed speciiers for the areas of reading, mathematics, and written expression.
Characteristics of Speciic Learning Disorder
Speciic learning disorder is diagnosed through a clinical review of the individual’s developmental, medical, educational,
and family history, reports of test scores and teacher observations, and response to academic interventions. The diagnosis
requires persistent dificulties in reading, writing, arithmetic, or mathematical reasoning skills during formal years of schooling. Symptoms may include inaccurate or slow and effortful reading, poor written expression that lacks clarity, dificulties
remembering number facts, or inaccurate mathematical reasoning.
Current academic skills must be well below the average range of scores in culturally and linguistically appropriate tests of
reading, writing, or mathematics. The individual’s dificulties must not be better explained by developmental, neurological,
sensory (vision or hearing), or motor disorders and must signiicantly interfere with academic achievement, occupational
performance, or activities of daily living.
Because of the changes in DSM-5, clinicians will be able to make this diagnosis by identifying whether patients are unable
to perform academically at a level appropriate to their intelligence and age. After a diagnosis, clinicians can provide greater
detail into the type of deicit(s) that an individual has through the designated speciiers. Just as in DSM-IV, dyslexia will be
included in the descriptive text of speciic learning disorder. The DSM-5 Neurodevelopmental Work Group concluded that
the many deinitions of dyslexia and dyscalculia meant those terms would not be useful as disorder names or in the diagnostic
criteria.
Broader Approach for Targeted Care
Broadening the diagnostic category relects the latest scientiic understanding of the condition. Speciic symptoms, such as
dificulty in reading, are just symptoms. And in many cases, one symptom points to a larger set of problems. These problems
can have long-term impact on a person’s ability to function because so many activities of daily living require a mastery of
number facts, written words, and written expression.
Early identiication and intervention are particularly important. The broader DSM-5 category of speciic learning disorder
ensures that fewer affected individuals will go unidentiied, while the detailed speciiers will help clinicians effectively target
services and treatment.
ARTICLES AND REVIEWS
A. Dificulties in accuracy or luency of reading that are not consistent with the person’s chronological age, educational opportunities, or intellectual abilities.
Multiple sources of information are to be used to assess reading, one of which must be an individually administered, culturally appropriate, and psychometrically sound standardized measure of reading and reading-related abilities.
(…)
Rationale
• Name change to dyslexia consistent with international use.
• Wording needs to be consistent with the change in the U.S.’s reauthorized IDEA regulations (2004) which states that: “the
criteria adopted by the State must not require the use of a severe discrepancy between intellectual ability and achievement
for determining whether a child has a speciic learning disability, as deined in 34 CFR 300.8(c)(10).”
• There is little evidence to support the DSM-IV criterion of a substantial discrepancy between achievement and intellectual ability (e.g., Fletcher et al., J Learn Disabil 1992; Vellutino et al. J Learn Disabil 2000; Siegel LS, J Learn Disabil 1989;
Stanovich KE, Learn Disabil Quarterly 2005; Stuebing K [2002, meta-analysis] Am Education Res Journal).
• (…)
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DIAGNOSING SPECIFIC LEARNING DISORDERS