Dyslexia - Definition and treatment
Since the end of the nineteenth century, dyslexia has been used as a term for certain severe reading and spelling problems. However, there are a great number of varied definitions of the precise meaning of this term. Some refer to the population in question, others to various explanatory factors and still others to observed symptoms. The committee believes that a working definition which will allow it to answer the questions asked should fulfil a number of conditions. It should be descriptive (with no explanatory elements), specific enough to be able to identify dyslexia within the whole of severe reading and spelling problems, general enough to allow for various scientific explanatory models and developments which those models may undergo, operationalizable for the purposes of research into people and groups, directive for statements concerning the need for intervention and, finally, recognizable for the various groupings involved. The committee has therefore arrived at the following working definition: dyslexia is present when the automatization of word identification (reading) and/or word spelling does not develop or does so very incompletely or with great difficulty.
The term ‘automatization’ refers to the establishment of an automatic process. A process of this kind is characterized by a high level of speed and accuracy. It is carried out unconsciously, makes minimal demands on attention and is difficult to suppress, ignore or influence. The working definition used means that dyslexia is characterized in practice by a severe retardation in reading and spelling which is persistent and resists the usual teaching methods and remedial efforts. Upon examination, it will be accompanied by very slow and/or inaccurate and easily disturbed word identification and/or word spelling. The committee has operationalized these characteristics further. This working definition allows for various causes and explanatory hypotheses, with both univariate and multivariate causes and for both single (dyslexia alone) and complex presentation forms. In all cases a partial and sometimes principal role is played by an person-bound factor. The committee believes that dyslexia can be seen as an (impairment or) disability in the sense of the International classification of Impairments, Disabilities and Handicaps (ICIDH).
This definition both extends and restricts the limits of the concept of dyslexia in comparison with previous definitions. On the one hand, the population is increased because no exclusion-criteria are included. In this way, retarded pupils or pupils with sensory defects can also be dyslexic. On the other hand, the definition delimits the group whose reading and spelling problems are characterized by severe and persistent problems with the automatization of technical reading and spelling. Only a small proportion of the children with reading and spelling problems fall within this category.
Dyslexia must be diagnosed and cannot be predicted. A few risk factors can, however, be stated. The main one is the failure of phonological skills to develop. These are skills needed to discriminate, recognize and use the phonetic (sound) structure of words. Furthermore, problems with the automatization of arbitrarily associations and a family history of severe reading-problems are to be regarded as risk-factors. However, dyslexia should not be associated unthinkingly with attention disorders, neurological disorders, problems with arithmetic, motivation problems, visual disorders, problems in visual/spatial skills, motor difficulties, co-ordination problems, articulation difficulties or language problems. In addition, there is no link between the occurrence of dyslexia and intelligence.
From observation to treatment
The timing of intervention is very important. The committee is of the opinion that the greatest benefit can be achieved if developing reading and spelling problems are dealt with promptly and adequately. The committee has therefore principally concentrated on early readers. This does not alter the fact that adolescents and adults with dyslexia can also require, and benefit from, information, treatment and compensation measures.
Every year, in the Netherlands almost 200,000 children start learning to read. The great majority learn to read quite naturally, almost regardless of the method used. Approximately ten per cent have so much difficulty that extra educational assistance is required. For some, even this is not enough. These children are potential dyslexia sufferers. This group should be selected in a systematic, phased and cyclical process of observation, intervention and evaluation within the educational system. The persistent nature of the problem can only be established in the course of a period of specific additional educational effort. On the one hand, the length of this period should prevent children being referred too quickly. On the other hand, the problems should be prevented from worsening as a result of the delay of effective measures. For various reasons, the committee has decided on a period of no more than six months of specific additional assistance within a school using all the aids and expertise available. The work carried out during that period should produce the desired result. This means that reading and spelling progress will be comparable in terms of speed with the average progress of a normal group. There should be a clear evaluation moment in the education system about three months before the end of the first year of reading education. From that moment onwards, severe and persistent problems with the automatization of word recognition and word spelling can be diagnosed reliably enough according to current knowledge. Specific additional assistance should be provided by this time at the latest but this should preferably and as a rule be done earlier.
The committee describes the process of observing risk factors and the initial signs of reading and spelling problems up to and including referral for specialized diagnosis and treatment. It notes that various factors can justify calling in specialized help at an earlier stage of development of the reading and spelling problem (skipping the ‘school approach’): previous serious language-developmental problems, family history of severe reading and spelling problems or dyslexia and medical problems in the past.
The size and composition of the group to be referred has proved to be partly dependent on the options which school and educational support institutions provide in a specific situation. The committee does not wish to make any definitive statements about the number of children with dyslexia. The literature states figures ranging from two to ten per cent. The committee believes that the number of children who develop severe reading and spelling problems can be reduced by systematic early intervention. Data from a few projects in the educational system indicates a figure in the region of one to three per cent of children who should be referred. Assuming this figure to be correct, it results in a estimate of approximately 6,000 new students per year who would qualify for specialist diagnosis and possible treatment.
Intervention: remediation and treatment
The committee makes a distinction between two levels of intervention, depending on responsibility and the required expertise: remediation including exploratory diagnostics needed for this purpose and the specialist treatment of dyslexia with the associated explanatory diagnostics.
Remediation makes use of a limited number of methods, is individual- or group-oriented and limited in intensity. Responsibility is primarily with the school team, in consultation with the regional network of schools for regular and special education and the educational support body. The concept of remediation can, in this context, mean both help from teaching staff or remedial staff and from a speech- and language therapist.
Specialist treatment takes place on the basis of a broad, more specialized and explanatory diagnosis and is exclusively directed towards individuals. The selection of a particular method of treatment is partly dictated by a hypothesis based on the diagnosis concerning the origin and persistence of the problem. Treatment almost always has to be intensive and long-term and is often multi-disciplinary. The responsibility for treatment is assigned to a specialist, usually a (educational) psychologist specialized in the diagnosis and treatment of learning difficulties or learning disorders.
It is not uncommon that, on the basis of a specialist diagnosis, the decision is taken to use a treatment modality which, in term of practical execution, is (in part) within the range of expertise of the first level. As long as the responsibility for content, progress and evaluation remains with the specialist, the committee refers to remedial work in the context of treatment.
Every intervention should take place in a way which makes it possible to account for the selected course of action. The committee notes that there are many therapists and therapies outside the boundaries of sound intervention modalities.
Specialist diagnosis and treatment
The treatment of people with dyslexia concentrates specifically on reading and spelling skills. However, it also involves aspects of therapeutic or remedial interaction and includes the provision of information and the promotion of appropriate compensation and, where appropriate, dispensation measures. It is of utmost importance to break out of a spiral of negative factors by creating experiences of success. The committee has limited itself to an evaluation of various treatment methods which concentrate specifically on reading and spelling skills, insofar as those methods have a scientific basis. The methods are classified into psycho-motor function training, neuropsychological treatment methods with, in particular, hemisphere-specific stimulation according to Bakker, task-specific treatment, the linguistic approach and treatment using compensatory, cognitive strategies. It has proved difficult to make statements about the effectiveness of various specific treatment methods on the basis of the literature. It is possible however to state which factors can reasonably be considered to have a positive effect on treatment and prognosis and which cannot.
The committee believes that, given current knowledge, the treatment of dyslexia should in any case be task-oriented. A task-oriented treatment aims at assessing deficiencies in reading and spelling skills and eliminating them by means of systematically built up subtasks. This means that, during the treatment process, use must be made of reading and spelling tasks which have been analyzed and selected by experts. There is reason to assume that task-oriented treatment is most effective when use is made of a combination of different methods which are directed on the one hand at the automatization of word identification and word spelling and on the other hand at compensation techniques. According to some, but not all, research on this topic, the use of hemisphere-specific or hemisphere-alluding stimulation can make a valuable contribution to the treatment of children with whom no results or inadequate results have been achieved. Additional research is required into the best application and scientific foundation. It is the opinion of the committee that psycho-motor function training, on the other hand, should not be linked to dyslexia or reading and spelling problems. It has been sufficiently demonstrated that it has no effect on reading and spelling skills.
Furthermore, the structure and planning of the treatment should take various explanatory models into account, as well as the findings of the individual diagnosis. The persistent nature of dyslexia means that treatment is, as a rule, intensive and long-term and that the results are difficult to predict. On the basis of its own clinical experience, the committee would estimate that treatment can be considered to be successful in approximately three quarters of the children treated. It discusses the limits of treatment and the situations in which - exceptionally - a second course of treatment can be justified.
The committee believes that there is, in the Netherlands, a need for well-structured and multi-disciplinary treatment research of adequate size. The conditions required for research of this kind are also in place. The committee is of the opinion that the departments of Health, Welfare and Sport and of Education, Culture and Science should make joint efforts to promote research of this kind.
The role of speech- and language therapists
The basis of speech- and language therapy for reading and spelling problems is the fact that deficient phonological skills interfere with the technical aspects of learning to read and spell. Given this, the committee sees a role for speech- and language therapy in connection with reading and spelling problems in the following situations:
- a possible preventive role linked to tracing and combating language and speech problems
- a role in the context of remediation of reading and spelling problems
- a role in the context of treatment for dyslexia.
Speech- and language screening of children at the age of five of the kind which takes place in the education system is primarily directed towards detecting language and speech disorders but there are indications that it might be used, when linked to early intervention in the form of the training of phonological skills, for the prevention of reading and spelling problems and probably for dyslexia also (in some cases). This takes place in the so called pre-reading stage.
With reading and spelling problems in the developmental stage, the use of speechand language therapy can be justified in certain situations. This is the case when the phonological skills which are so important for reading are not developing before or in parallel with early reading. It makes sense to impose limits on the duration of training as well as on the period in which such training can sensibly be commenced. In terms of content, the most obvious step is linkage to early reading in the first year of reading education.
During educational progress, reading development becomes increasingly intertwined with further cognitive development. The committee considers that broader remedial expertise is required after the first year of education for the treatment of reading and spelling problems in all conditions. Registered remedial teachers have this expertise with regard to a range of learning difficulties. The committee would not exclude the possibility that, particularly in the case of children whose reading and spelling problems are associated with general language problems, speech- and language therapists can also provide remedial assistance with reading and spelling problems after the first year of education. It believes that these speech- and language therapists should have acquired demonstrably broader remedial expertise based on training and experience. The committee believes that the profession has a responsibility to safeguard the required expertise by means of conditions for regular, additional and refresher training and professional experience, as well as conditions relating to the working methods. It is of the opinion that consultation is required for this purpose between the professional associations of speech- and language therapists and remedial teachers. Remedial assistance from a qualified speech- and language therapist after the first year of education is, in the opinion of the committee, part of educational support.
Finally, speech- and language therapy can be indicated in the context of the specialist treatment of dyslexia based on the explanatory diagnosis and the treatment plan and under the supervision of the specialist.
However, the committee does not believe that dyslexia can be used as an indication for referral to a speech- and language therapist or for calling in a remedial teacher without the mediation of a specialist in the field of the diagnosis and treatment of learning difficulties.
The role of other professionals
In addition to parents, general practitioners, doctors in child health clinics, school medical officers, paediatricians, other doctors and speech- and language therapists, teachers from the first year of education onwards in particular have a role to play in observing risk factors. Teachers of the first year of reading-education have a special responsibility for the early observation and intervention of reading and spelling problems. The committee believes that the diagnosis, indication and treatment of severe, persistent and complex reading and spelling problems should be carried out by, or under the supervision of, a (educational) psychologist specialized in the diagnosis and treatment of learning difficulties. In the future, it is expected that these professionals will be registered as health care psychologists in the context of the Individual Health Care Professions Bill. Depending on the problem and the situation, experts from a variety of disciplines can play a role. Examples would be neuropsychologists, doctors from various medical specialisms and experts in the field of neurophysiological research. In the case of complex problems, there should be treatment by a multi-disciplinary team, with agreements being made about everyone’s role and responsibility. In many cases, children are involved who also suffer from psychiatric problems. This should be borne in mind in the organizational design of treatment options.
Education and health care
The whole process of observation through to the treatment of dyslexia is a problem which transcends the departmental distinction between education and health care. The committee believes that the main responsibility in the field of remedial work with reading and spelling difficulties is with education, whereas the specialist diagnosis and treatment of dyslexia must be considered to be a task for health care. There is a certain overlap if the initial stage of reading education proceeds with great difficulty and phonological skills fail to develop adequately or when the assistance from the education system produces insufficient results and there is a danger that the child will develop severe emotional or social problems. The committee believes that the response to reading and spelling problems should, on the one hand, do justice to this link between education and health care but that it is necessary to avoid an unjustified transfer of tasks which are primarily educational to health care. The linkage between education and health care should be monitored and managed (and also be monitorable and manageable). The committee proposes, in line with developments concerning referral to Special Education, drawing up requirements for the initial stages of the process in the education system, as well as for the indications for treatment. It advocates joint involvement of the Ministers of Education, Culture and Science and of Health, Welfare and Sport in order to ensure a sound, efficient and just system of intervention options.
Organization and capacity of diagnosis and treatment
Specialist diagnosis takes place in various locations with many different financing and payment methods. However, specialist treatment principally takes place as a form of out-patient psychotherapy at a limited number of institutions specialized in the field of child and adolescent psychiatry and at self-employed partnerships and private practices. Data are available about the extent of the assistance provided for the first option only. In total, approximately 120 children per year with generally complex problems start treatment. The average number of ‘sessions’ is, according to available data, between 60 and 75 per child during a period of about one year to eighteen months. It is estimated that another 30 or 40 children qualify for intake or diagnosis without specialist treatment being given. At some institutes, there are waiting lists of a few months to a year, while at present, the children involved have often stopped progressing in educational terms some time previously. The committee cannot say how much treatment is given in private practices and institutes. It assumes that single problems are more often found here. Furthermore, the committee knows from experience that many children do not receive the treatment they require or do not receive it in time.
The current situation in terms of the availability and reimbursement of expert intervention does not ensure that this help is available for everyone equally. It is far from being the case that every school has a remedial teacher. Remedial work often has to be paid for by the clients themselves. Only a few health insurance schemes reimburse speech- and language therapy for dyslexia, either directly or under other categories. Specialist diagnosis and treatment does not have to be paid for individually in some cases. In other cases, it must be paid for in part or in whole, while the options for claiming expenses from an insurer differ according to the situation.
Children with simple dyslexia can, in principle, be helped by qualified (educational) psychologists in solo-practice, where appropriate in collaboration with remedial experts. A drawback of a solo-practice can be the lack of professional consultation and review. Most of the experts however can be found in organizational contexts. It can be expected of the professions in question to assume responsibility for the sound development of this specific function. They should, among other things, formulate requirements for training, professional experience, working methods and consultation structures. A few institutions could fulfil a pioneering role here. The government can stimulate and make possible this development in various ways. In so doing, a policy decision will be required about whether the emphasis will be on individual providers of treatment and room for a variety of developments or whether there will be an orientation towards certain organizational contexts into which providers of treatment can or must be recruited.
For children with complex problems, multi-disciplinary diagnosis and, in many cases, treatment is necessary. What is involved here is a combination of expertise in the field of learning difficulties, child and adolescent psychiatry and, where necessary, other medical disciplines. A structure which makes this possible is now in place in about five locations in the Netherlands. The committee believes that this provision should be equally available and accessible for everyone and advocates widening the opportunities in this area, especially in the regions where facilities of this kind are not yet in place. It estimates that between eight and ten of these combined facilities are needed. Centres for child study and child guidance (PI’s and ambulatoria) and possibly educational support institutes (OBD’s) on the one hand, and institutions for child and adolescent psychiatry on the other hand (possibly in collaboration with Regional Institutes for Out-Patient Mental Health Care (RIAGGs), can be asked to develop this service.