1. The programme at a glance
Indication. A child, adolescent or adult in whom a specific learning disorder is suspected or has been diagnosed: a lasting difficulty in learning to read, to write and spell, or to calculate, which is explained neither by intellectual disability, nor by a visual or hearing impairment, nor by the teaching received, nor by the language of schooling. Everyday usage speaks of dyslexia, dysorthographia and dyscalculia (section 3). The manual also applies when the request first concerns anxiety, a refusal to go to school, low mood or conflicts over homework, and the learning disorder is the background to it.
What this manual does. It is a practice guide, without numbered sessions. Its readers, psychologists and psychiatrists, do not conduct the remediation of reading, spelling or arithmetic: in France, that falls mainly to the orthophoniste, the speech and language therapist, and elsewhere to a remedial teacher, a specialist teacher or a language therapist. A session protocol would describe work that you do not do. This manual describes what you actually do: identify, rule out other explanations, assess, read other professionals' assessment reports, give the diagnosis, judge progress, treat the associated psychological difficulties, coordinate with the school, and see the person again at transitions.
Who does what. The psychologist's part is the history of development and schooling, the cognitive assessment when it answers a question, the critical reading of other assessments, giving the diagnosis, the treatment of anxiety, mood, self-esteem and family conflict, and often coordination. The psychiatrist's part is differential diagnosis, suicide risk, the treatment of associated disorders, including medication, and certain certificates. Other professionals take on the assessment and remediation of language and of mathematical cognition (speech and language therapist or equivalent), of motor skills and handwriting (psychomotor therapist, occupational therapist), the examination of vision and hearing, and the adaptation of teaching. In France, the child's doctor or the school doctor of the Éducation nationale, the French state education system, often coordinates the pathway (Haute Autorité de santé, 2017).
The pathway. It replaces the table of sessions. Each step may take one or more appointments, and some overlap.
| Step |
What falls to the psychologist or psychiatrist |
What comes out of it |
| 1. Welcoming and identifying |
Gathering the request, the history of development and schooling, the help already received and the response to that help |
A hypothesis, or first some targeted teaching support |
| 2. Ruling out other explanations |
Checking vision, hearing, the teaching received, language, absenteeism, intellectual functioning, the context |
The examinations carried out or requested |
| 3. Assessing |
Coordinating the assessments, carrying out the cognitive assessment when it is useful, reading other professionals' assessments |
A diagnosis made, ruled out or deferred, with its arguments; worksheet 8 for the adolescent or adult |
| 4. Giving the diagnosis |
Explaining the disorder to the child, the parents, the adolescent or the adult |
Worksheets 1 and 2 |
| 5. Assessing the impact and treating what can be treated |
Looking for anxiety, depression, school refusal, damage to self-esteem, conflicts over homework, suicide risk |
A care plan, initial measures, worksheet 5 |
| 6. Coordinating |
Writing the report and the letter to the school, preparing the meeting, following up the adjustments |
Worksheets 3, 4 and 6 |
| 7. Following up |
Seeing the person again at transitions, judging progress by reliable change, deciding when to repeat an assessment |
Worksheet 7, a follow-up schedule |
What the family or the person takes away. They take away eight printable worksheets, listed in section 22: understanding my child's disorder, what helps me, my school passport, preparing the meeting with the school, homework without conflict, keeping track of adjustments, preparing a transition, and my questions for the assessment.
What sets this manual apart from the other manuals on this site. It is the only one without sessions, and this is deliberate: the disorder is remediated elsewhere, and your role is to diagnose, explain, coordinate and treat its impact, from childhood to adulthood. The other manuals encounter these disorders as a diagnosis to be ruled out or as a co-occurring condition: Treating ADHD in children: a therapist's manual and Treating ADHD in adults: a therapist's manual distinguish them from an attention disorder, and Treating anxiety-based school refusal: a therapist's manual looks for them behind a refusal to go to school. This manual says how to look for them, confirm them and support the person, and refers to those protocols for the rest.
2. Before you begin
The four preliminary decisions
Who is consulting, and for what? Worried parents, a teacher who has suggested an assessment, an adolescent who is disengaging from school, an adult who has always read slowly: note down each person's request, and ask the child what they think about it; they are sometimes the only one who does not know why they are there.
Where does the diagnosis stand? A hypothesis, a diagnosis under way, one made long ago, or one that is disputed: depending on the case, you will build the assessment (sections 7 and 8), reread assessment reports (section 9), support a known diagnosis (sections 15 and 16) or revisit a doubtful diagnosis (section 21).
Does distress or a risk come first? Thoughts of death, bullying, entrenched school refusal, or violence around homework have their own course of action in section 11, and it comes before the assessment of learning.
Who is already doing what? Before requesting one more assessment, find out what already exists: remediation, support at school, a doctor who coordinates. Many families accumulate assessments that nobody links together; your first contribution is often to bring order to what has already been done.
What this manual does not cover
It does not describe remediation. It says what research establishes about it (section 13), so that you can advise families.
It does not cover intellectual disability, except when a learning disorder is added to it, that is, when the difficulties clearly exceed what the disability explains (American Psychiatric Association, 2013).
It does not cover, as its main subject, developmental language disorder, developmental coordination disorder or autism. It places them (section 3) and says when to consider them (section 10); autism in children has its own manual, Autism in children and adolescents: a therapist's manual.
It does not replace the protocols for anxiety, depression or school refusal. It says how to adapt them for a person who has a learning disorder (section 16), and refers to the manuals that describe them.
Who does what, by country
In France, by way of example, the Haute Autorité de santé, the French national health authority (2017), describes a three-level pathway: front-line professionals, including the child's doctor, who prescribes the speech and language therapy assessment, since speech and language therapy (orthophonie) is provided on medical prescription (a provision of French law; elsewhere, the local equivalent); for complex situations, a multidisciplinary team trained in language and learning disorders, under the responsibility of a doctor, with a psychologist specialised in neuropsychology; and for the most complex situations, hospital reference centres.
Elsewhere, remediation may fall to a remedial teacher, a specialist teacher, a speech and language therapist or the school, and the diagnosis to a school psychologist or a neuropsychologist. Everywhere, each professional does what falls within their training, and someone links it all together: know how this is divided up in your country before promising anything to a family.
How to use it
Read sections 4, 8 and 9 first: the classifications, assessment and reading an assessment report. That is where mistakes cost the most, in either direction: a diagnosis made on a single test, or refused because the IQ does not "fit". The pathway in section 1 serves as a thread, with no fixed duration. As in the other manuals on the site, most sections set out what you say and the common mistakes, without session numbers.
3. "Troubles dys": what the term covers
A word in everyday use, not a diagnosis
In France, people commonly speak of "troubles dys", that is, "dys" disorders. The Haute Autorité de santé uses the expression specific language and learning disorders, which it says are "commonly called troubles dys", and groups under it difficulties with oral language, written language, arithmetic, motor skills and spatial organisation, as well as so-called cross-cutting functions such as attention, memory and executive functions (Haute Autorité de santé, 2017). This grouping has a public health logic — frequent disorders of cognitive development, often associated with one another, which call for a coordinated pathway —, but it brings together under a single word diagnoses that the classifications keep separate, and the referral is not the same for each.
What belongs to the learning disorders
Dyslexia is a lasting difficulty in recognising written words accurately and fluently, in decoding and in spelling. DSM-5 uses this word for this profile, while asking for any other difficulties, such as comprehension, to be specified as well (American Psychiatric Association, 2013). A recent expert consensus describes it as a difficulty with reading and spelling associated with several factors, often accompanied by other developmental disorders, of which reading fluency and spelling are key markers, depending on age and on language (Carroll et al., 2025).
Dysorthographia — the French term "dysorthographie", for a lasting difficulty with spelling — falls under the "written expression" form of the disorder (section 4). It very often accompanies dyslexia, but it may persist on its own in an adolescent or adult who has learned to read correctly.
Dyscalculia is a lasting difficulty in understanding quantities and numbers, in remembering arithmetic facts and in calculating accurately and fluently; DSM-5 also uses this word for this profile (American Psychiatric Association, 2013).
What belongs to other diagnoses
"Dysphasia" ("dysphasie") is the former French name for what an international consensus calls developmental language disorder: a lasting difficulty with oral language, in comprehension or expression, which interferes with everyday life and is not linked to a known medical cause (Bishop et al., 2017). ICD-11 classifies it separately, under code 6A01.2. It is not a learning disorder, but the two often coexist, and a recent review stresses the role of oral language in reading and how frequently the two are associated (Snowling and Hulme, 2021).
"Dyspraxia" ("dyspraxie") most often corresponds to developmental coordination disorder: an acquisition of coordinated motor skills well below what is expected for age, with clumsiness, slowness or imprecision that interfere with everyday life and schooling (Blank et al., 2019). ICD-11 classifies it under code 6A04. Handwriting that is slow, effortful or illegible often comes under this disorder, and not under a learning disorder.
"Dysgraphia" is not a category in the classifications. The word refers to a difficulty with handwriting, which belongs to coordination disorder when it is the motor act that is affected, and to the written expression disorder when it is spelling, syntax or the organisation of the text.
Attention-deficit/hyperactivity disorder (ADHD) is sometimes classed among the "dys" disorders. It is a distinct disorder, which is often associated with learning disorders (section 10).
Why this matters in practice
Referral follows the diagnosis. A reading difficulty linked to an oral language disorder calls for work on oral language as much as on decoding; illegible handwriting in a good reader calls for an assessment of motor skills, not for spelling remediation. And a child described as "dys" with no further detail does not yet have a diagnosis: you ask which one, made by whom, on what grounds.
What you say
"The word 'dys' is an everyday word that groups together several different disorders. For your son, what is involved is reading and spelling: that is what we call dyslexia. His handwriting, on the other hand, is fine, and there is no difficulty with spoken language."
Common mistakes
Accepting "he is dys" as a diagnosis. The word says neither which area is affected, nor how severely, nor what assessment it rests on. Ask for the assessment reports and reread them before building anything on them.
Confusing slow handwriting with dysorthographia. An adolescent who writes slowly and badly may spell correctly when typing or dictating; it is then the motor act that is costly, and the help needed is not the same.
4. What the classifications say
The categories, reformulated
The wording below is a reformulation in our own words, intended as a reminder. It does not replace the manuals: refer to DSM-5-TR (American Psychiatric Association, 2022) and ICD-11 (World Health Organization, 2022) for the wording itself.
Specific learning disorder, in DSM-5-TR. A single category, which since DSM-5 has brought together what were previously four separate diagnoses (American Psychiatric Association, 2013). It rests on four elements.
The first is a difficulty in learning and using one or more basic academic skills — reading words accurately and without excessive slowness, understanding what is read, spelling, expressing oneself in writing, mastering number sense, arithmetic facts and calculation, reasoning mathematically —, which has persisted for at least six months even though help targeting it has been provided. This point is central: a child who catches up with classmates when given appropriate help does not have a disorder; they lacked teaching.
The second is a level clearly and measurably below what is expected for age, which interferes with schooling, work or everyday life, confirmed by individually administered standardised tests and by a comprehensive clinical assessment. From the age of 17, a documented history of impairing learning difficulties may take the place of standardised tests.
The third is onset during the school years, even if the disorder only becomes fully apparent when demands exceed the person's capacities, with timed exams or a heavy workload: hence diagnoses made in lower or upper secondary school, or later.
The fourth is that the difficulties are not better explained by intellectual disability, uncorrected loss of vision or hearing, another mental or neurological disorder, psychosocial adversity, insufficient proficiency in the language of instruction, or inadequate teaching.
The three forms, and their codes. DSM-5-TR asks for each affected area to be specified, and each has its own code: with impairment in reading, F81.0 (accuracy of decoding, speed or fluency, comprehension); with impairment in written expression, F81.81 (accuracy of spelling, of grammar and of punctuation, clarity and organisation of the text); with impairment in mathematics, F81.2 (number sense, memorisation of arithmetic facts, accurate or fluent calculation, mathematical reasoning). When several areas are affected, each one is coded.
Severity. DSM-5-TR distinguishes three levels: mild, when the person can compensate for difficulties limited to one or two areas thanks to adjustments or support; moderate, when marked difficulties require periods of intensive, specialised teaching, and adjustments part of the time; severe, when several areas are affected and intensive, individualised teaching remains necessary for most of the school years, without everything becoming possible even with adjustments.
The threshold. The text accompanying the criteria does not set a mandatory threshold, and it points out that academic skills are distributed continuously, with no natural boundary. It indicates that a score at least 1.5 standard deviations below the mean for age, that is, a standard score of 78 or less, below the 7th percentile, gives the greatest diagnostic certainty, and that a more lenient threshold, between 1 and 2.5 standard deviations, may be used when several sources agree (American Psychiatric Association, 2013); DSM-5-TR keeps this benchmark. Section 9 explains how to read these figures.
What ICD-11 adds
ICD-11 speaks of developmental learning disorder, under code 6A03 (World Health Organization, 2022): a significant and persistent difficulty in acquiring reading, writing or arithmetic, with performance well below what is expected for age and for the level of intellectual functioning, which appears when these skills are taught in the first years of school and interferes with schooling or work. It excludes the same explanations as the DSM, including lack of access to education, insufficient proficiency in the language of instruction and psychosocial adversity.
Its subcategories are 6A03.0, with impairment in reading (accuracy of decoding, fluency, comprehension); 6A03.1, with impairment in written expression (spelling, grammar and punctuation, organisation and coherence of ideas); 6A03.2, with impairment in mathematics (sense of quantities and numbers, memorisation of number facts, accurate and fluent calculation, reasoning); 6A03.3, for another specified impairment; and 6A03.Z, for an unspecified form. So-called developmental dyslexia and developmental dyscalculia are among the index terms of 6A03.0 and 6A03.2.
A nuance. ICD-11 keeps a reference to intellectual level, whereas DSM-5-TR merely excludes intellectual disability; in practice, neither requires a quantified discrepancy between IQ and performance.
What has changed
The end of the discrepancy criterion. For decades, dyslexia was defined by a discrepancy between IQ and reading level: a child with a high IQ who read poorly was dyslexic, a child with an average IQ who read just as poorly was not. This criterion was abandoned because no difference in kind was found between these two groups of poor readers, either in reading or in the processing of the sounds of language, and because faulty decoding calls for the same interventions whatever the IQ (Snowling et al., 2020). Brain imaging points the same way: the reduced activation of the brain regions linked to sound processing is the same in poor readers, whether their IQ is high or not (Tanaka et al., 2011). The international consensus on language disorder made the same choice (Bishop et al., 2017).
Response to intervention. DSM-5 replaced the discrepancy with persistence despite targeted help: appropriate teaching support is provided first, and you look at how the child responds to it. The Haute Autorité de santé (2017) does the same: a difficulty that persists after three to six months of differentiated teaching, or that is severe from the outset, calls for a medical assessment. This criterion assumes that the help was real, targeted and sufficient, which is not always the case: ask precisely what was done, for how long, and with what result (section 7).
A diagnosis that has become less strict. By relaxing the criteria, fairness was gained, since children with an average IQ are no longer excluded, but some authors consider that clarity was lost, as the word dyslexia now covers very different realities depending on who uses it (Snowling et al., 2020). In concrete terms, two assessment reports that conclude dyslexia may rest on criteria that have nothing in common.
What the classifications do not say and must be assessed
They do not say what the person experiences — the shame of reading aloud, the exhaustion of homework, the idea of being stupid —, nor how the school has responded, nor what is going well, even though strengths are the basis of any useful explanation and of any plan for the person's educational or career direction. And their criteria say nothing about suicide risk, which the DSM-5 accompanying text nevertheless associates with this disorder, in children, adolescents and adults (American Psychiatric Association, 2013; section 11).
5. How common it is, in whom, and how it develops
Figures that depend on the threshold
The DSM-5 text put the frequency of the disorder, all areas combined, at between 5 and 15% of school-age children, and at around 4% in adults, a figure it described as poorly known (American Psychiatric Association, 2013). DSM-5-TR keeps the range of 5 to 15%, attributing it to studies carried out in Brazil, Northern Ireland and the United States, but no longer gives a figure for adults, whose frequency is described as unknown (American Psychiatric Association, 2022). The collective expert review by Inserm, the French national institute for health and medical research, estimates, on the basis of the most rigorous international studies, that dyslexia affects at least 3 to 5% of children around the age of 10 (Inserm, 2007). The Haute Autorité de santé puts forward an order of magnitude of 8% for all language and learning disorders, oral language and coordination included (Haute Autorité de santé, 2017).
These figures do not contradict each other: they do not measure the same thing. Reading and arithmetic skills are distributed continuously, and the proportion of people "affected" depends on the threshold and the tests chosen: a single study found, depending on the definition used, between 3.6 and 8.5% of children with dyslexia in Italy and between 4.5 and 12% in the United States (Inserm, 2007). Remember the idea rather than the figure: a frequent disorder, present in almost every class, whose boundary is a convention.
Isolated dyscalculia is considered rarer than dyslexia in the most rigorous studies, even though one often reads that the two are equally frequent (Inserm, 2007).
Forms that occur together
The three forms occur together more often than chance would predict. Among 1,633 German-speaking children in the third and fourth years of primary school, combined disorders were as frequent as isolated ones, and arithmetic difficulties were more often associated with spelling difficulties than with reading difficulties (Moll et al., 2014). In another population study, a child with marked difficulty in one area was four to five times more likely to have difficulty in another (Landerl and Moll, 2010). When one area is affected, look at the other two.
Boys and girls
The DSM-5 text indicates that the disorder is more frequent in boys, by two to three to one (American Psychiatric Association, 2013), a ratio that DSM-5-TR repeats, and four large epidemiological studies have confirmed this excess for reading, which rules out the idea of mere referral bias (Rutter et al., 2004). This bias nevertheless widens the gap in clinical settings: the authors of a twin study point out that there are about four boys for every girl in referred samples, against 1.2 to 1.5 in non-referred samples, and they propose an explanation: the restlessness of dyslexic boys attracts more attention than the silent inattention of girls (Willcutt and Pennington, 2000). Arithmetic is the exception: girls more often have difficulties with it, and spelling affects boys more (Landerl and Moll, 2010; Moll et al., 2014).
What this changes: a quiet girl who reads poorly is a diagnosis that gets missed, because she bothers nobody.
A disorder that lasts, and changes shape
The disorder is lasting, and the gap shows early: in a cohort of 414 children followed every year from the first year of school to the last year of secondary school, the reading gap between dyslexic children and the others was present from the first year of school and did not close over the years (Ferrer et al., 2015).
What changes with age is the form: the adolescent often decodes, but slowly and at the cost of constant effort, and their difficulties shift towards understanding long texts, written expression and spelling (American Psychiatric Association, 2013). In adults, a meta-analysis of 178 studies shows persistent reading and writing difficulties, more marked for speed than for accuracy, with comprehension less affected than decoding (Reis et al., 2020).
Depending on the language
The form of the disorder depends on the written language. In all the languages studied, learning to read relies on awareness of the sounds of the language, but languages differ in how regularly their writing transcribes speech, and this changes the way dyslexia shows itself (Ziegler and Goswami, 2005). In English, the most visible sign is reading that is both inaccurate and slow; in more regular writing systems, such as Spanish or German, and in non-alphabetic writing systems such as Chinese or Japanese, it is above all reading that is accurate but slow (American Psychiatric Association, 2013). In adults too, deficits are less marked in regular writing systems (Reis et al., 2020).
What this changes: in a regular language, a child who reads without errors may be dyslexic. It is speed that needs to be looked at.
What is passed on
The disorder runs in families. The DSM-5 text reports a risk four to eight times higher for reading, and five to ten times higher for mathematics, in first-degree relatives of an affected person, and a high heritability, above 0.6, of reading abilities as well as reading difficulties, in alphabetic as in non-alphabetic writing systems (American Psychiatric Association, 2013); DSM-5-TR repeats these figures. A meta-analysis of the studies that followed children at family risk of dyslexia shows that these children more often have, from their first years, a language delay, then difficulties in sound processing, letter knowledge and rapid naming; even those who do not become dyslexic read less well on average than other children (Snowling and Melby-Lervåg, 2016).
Heritability is not destiny: it does not mean that the environment does not matter. The DSM-5 text also cites very premature birth, very low birth weight and prenatal exposure to tobacco, and points out that no genetic test, no brain imaging and no single cognitive test is used for diagnosis today (American Psychiatric Association, 2013). The environment carries weight: with the same definition, an old British study found 3.6% of children with dyslexia on the Isle of Wight and 9.3% in more deprived areas of London (Inserm, 2007).
What the disorder costs when it is not supported
The DSM-5 text describes consequences throughout life — shorter schooling, more school dropout, greater psychological distress, more unemployment and lower income — and adds that strong social and emotional support predicts better mental health (American Psychiatric Association, 2013). This last lever is yours: support, explanation and protection from humiliation.