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Archive for September, 2012

ADHD diagnosis: research

ADHD Is Over-Diagnosed, Experts Say

Source: ScienceDaily, 2012

What experts and the public have already long suspected is now supported by representative data collected by researchers at Ruhr-Universität Bochum (RUB) and University of Basel: ADHD, attention deficit hyperactivity disorder, is over-diagnosed. The study showed that child and adolescent psychotherapists and psychiatrists tend to give a diagnosis based on heuristics, unclear rules of thumb, rather than adhering to recognized diagnostic criteria. Boys in particular are substantially more often misdiagnosed compared to girls.

These are the most important results of a study conducted by Prof. Dr. Silvia Schneider and Prof. Dr. Jürgen Margraf (both from RUB) and Dr. Katrin Bruchmüller (University of Basel) as reported in the periodical Journal of Consulting and Clinical Psychology.

Daniel has ADHD, Danielle does not 

The researchers surveyed altogether 1,000 child and adolescent psychotherapists and psychiatrists across Germany. 473 participated in the study. They received one of four available case vignettes, and were asked to give a diagnoses and a recommendation for therapy. In three out of the four case vignettes, the described symptoms and circumstances did not fulfil ADHD criteria. Only one of the cases fulfilled ADHD criteria based strictly on the valid diagnostic criteria. In addition, the gender of the child was included as a variable resulting in eight different case vignettes. As the result, when comparing two identical cases with a different gender, the difference was clear: Leon has ADHD, Lea doesn’t.

The “prototype” makes the difference

Many child and adolescent psychotherapists and psychiatrists seem to proceed heuristically and base their decisions on prototypical symptoms. The prototype is male and shows symptoms such as motoric restlessness, lack of concentration and impulsiveness. In connection with the gender of the patient, these symptoms lead to different diagnoses. A boy with such symptoms, even he does not fulfil the complete set of diagnostic criteria, will receive a diagnosis for ADHD, whereas a girl will not. Also the therapist’s gender plays a role in the diagnostic: male therapists give substantially more frequently a diagnosis for ADHD than their female counterparts.

Diagnostic inflation, more medication, higher daily doses

In the past decades the diagnoses ADHD have become almost inflationary. Between 1989 and 2001, the number of diagnoses in German clinical practise increased by 381 percent. The costs for ADHD medication, such as for the performance-enhancer methylphenidate (Ritalin), have grown 9 times between 1993 and 2003. The German health insurance company, Techniker, reports an increase of 30 percent in methylphenidate prescriptions for its clients between the ages of 6 and 18. Similarly, the daily dosage has increased by 10 percent on average.

Remarkable lack of research

Considering these statistics, there is a remarkable lack of research in the diagnostic of ADHD. “In spite of the strong public interest, only very few empirical studies have addressed this issue,” Prof. Schneider and Dr. Bruchmüller point out. While in the 70s and 80s a “certain upswing” of studies on the frequency and reasons for misdiagnoses could be observed, current research hardly examines the phenomena. The current study shows that in order to avoid a misdiagnosis of ADHD and premature treatment, it is crucial for therapists not to rely on their intuition, instead to strictly adhere to defined, established diagnostic criteria. This is best possible with the help of standardized diagnostic instruments, such as diagnostic interviews.

Vision and ADHD (2)

Rouse et al., in 2009, also conducted a study to determine whether children with symptomatic convergence insufficiency, without the presence of parent-reported Attention Deficit Hyperactivity Disorder (ADHD) had higher scores using a questionnaire on school behavior, the ABS Academic Behavior Survey.

The group of optometrists developed a questionnaire called the Academic Behavior Index (ABS). The Academic Behavior Survey is a 6-item survey that evaluates parent concern about school performance and the parents’ perceptions of the frequency of problem behaviors that their child may exhibit when reading or performing schoolwork (such as: difficulty completing work, avoidance, and inattention). The survey was administered to the parents of 221 children 9-17 years old with symptomatic convergence insufficiency and to 49 children with normal vision.

The results of this study showed that 15% of the convergence insufficiency group and children with normal vision were classified as ADHD by parental report. The total ABS score for the symptomatic convergence insufficiency with parent-report of ADHD group was significantly higher than the symptomatic convergence insufficiency with no parent-report of ADHD group. The authors concluded that both children at risk for ADHD or related learning problems should have a comprehensive vision evaluation to assess the presence of convergence insufficiency as a contributing factor.

The ABS questionnaire:

  • How often does your child have difficulty completing assignments at school?
  • How often does your child have difficulty completing homework?
  • How often does your child avoid or say he/she does not want to do tasks that require reading or close work?
  • How often does your child fail to give attention to details or make careless mistakes in schoolwork or homework?
  • How often does your child appear inattentive or easily distracted during reading or close work?
  • How often do you worry about your child’s school performance?

The symptoms frequently reported in convergence insufficiency such as loss of concentration when reading or reading slowly are similar to behaviors associated with ADHD (inattentive type), such as, failure to complete assignments and trouble concentrating in class.

The same team of optometrists in 2012, sought to determine whether treatment of symptomatic convergence insufficiency had an effect on the scores of the questionnaire Academic Behavior Survey (ABS), used previously.

The ABS was administered at baseline and after 12 weeks of treatment to the parents of 218 children aged 9 to 17 years with symptomatic CI, who were enrolled in the Convergence Insufficiency Treatment Trial and randomized into (1) home-based pencil push-ups; (2) home-based computer vergence/accommodative therapy and pencil push-ups; (3) office-based vergence/accommodative therapy with home reinforcement; and (4) office-based placebo therapy with home reinforcement. Participants were classified as successful (n = 42), improved (n = 60), or non-responder (n = 116) at the completion of 12 weeks of treatment using a composite measure of the all visual tests.

A successful or improved outcome after the convergence insufficiency treatment was associated with a reduction in the frequency of adverse academic behaviors and parental concern associated with reading and school work as reported by parents.

ADHD and Vision

Children with undetected vision problems can exhibit symptoms similar to ADD.  Studies show that approximately 20% of school-aged children suffer from eye teaming or focusing deficits which make remaining on task for long periods of time difficult.  Like those with ADD, children with vision-based learning problems are highly distractible, have short attention spans, make careless errors, fail to complete assignments, and are often fidgety and off task.  However, their inability to remain on task is caused by the discomfort of using their eyes for long periods of time at close ranges, not true deficits in attention.  Unfortunately, parents and teachers are not trained to recognize the difference and these children are often misdiagnosed.

These children are often looking around the room, getting a drink, going to the bathroom, staring out the window, or talking to their neighbors.  They’re taking “vision breaks,” although they don’t realize that’s what they’re doing. Children with eye teaming problems have always seen this way, and most are not aware that their close-up vision is not normal.  Few report eye strain or blurred or double print; all they know is that they cannot continue with their seat work one more moment.  As the day progresses, they become increasingly fatigued and frustrated

Any child who is suspected of having ADD should have a complete eye exam by a pediatric specialist in children’s vision to determine if poor visual processing is a factor in the child’s behavior.  Unlike ADD  is diagnosed by a subjective checklist, objective clinical measures and tests can be run to determine for certain if the child has a learning-related vision problem which is making it difficult for him to remain on task.

25% of Children May Have a Learning-Related Vision Problem (source: www.covd.org)

Research supports what optometrists have known for some time — a significant percentage of children with learning disabilities have some type of vision problem.  One study found that 13% of children between nine and thirteen years of age suffer from moderate to marked convergence insufficiency, and as many as one in four, or 25%, of school age children may have a vision problem that can affect learning. If we now consider visual-perceptual problems, nearly 60 % of children with learning problems will sow these types of problems.

ADHD questionnaire

The DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, fourth edition) contains the Diagnostic Criteria for diagnosing Attention Deficit (Hyperactivity) Disorder:


The child:

  1. Often fails to give close attention to details or makes careless mistakes in schoolwork, work, or other activities 
  2. Often has difficulty sustaining attention in tasks or play activities
  3.  Often does not seem to listen when spoken to directly
  4. Often does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace (not due to oppositional behaviour or failure of comprehension)
  5. Often has difficulty organizing tasks and activities
  6. Often avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort (such as schoolwork or homework)
  7.  Often loses things necessary for tasks or activities at school or at home (e.g. toys, pencils, books, assignments)
  8. Is often easily distracted by extraneous stimuli
  9. Is often forgetful in daily activities

It is interesting to note that five behaviors (outlined above) out of the 9 present in the DSM-IV may also be due to visual-perceptual problems!


What is important to consider in a visual and perceptual examination in presence of a child who suffers from an attention deficit disorder?

We must clearly identify the following visual and perceptual aspects that modulate visual attention and concentration:

  • Eye movements
  • Functional problems such as problems focusing, eye alignment and convergence problems (excess or insufficiency)
  • Visual attention skills
  • Visual discrimination skills
  • Visual memory skills


• Borsting E, Rouse M, Chu R. Measuring ADHD behaviors in children with symptomatic accommodative dysfunction or convergence insufficiency: a preliminary study. Optometry 2005;76:588-92.

• Granet DB, Gomi CF, Ventura R, Miller-Scholte A. The relationship between convergence insufficiency and ADHD. Strabismus 2005;13:163-68.

• Gronlund MA, Aring E, Landgren M, Hellstrom A. Visual function and ocular features in children and adolescents with attention deficit hyperactivity disorder, with and without treatment with stimulants. Eye 2007;21:494-502.

• Rouse M, Borsting E, Mitchell GL, Kulp MT, Scheiman M, Amster D, Coulter R, Fecho G, Gallaway M.Academic behaviors in children with convergence insufficiency with and without parent-reported ADHD. CITT Study Group. Optom Vis Sci. 2009 Oct;86(10):1169-77.

• Borsting E, Mitchell GL, Kulp MT, Scheiman M, Amster DM, Cotter S, Coulter RA, Fecho G, Gallaway MF, Granet D, Hertle R, Rodena J, Yamada T; CITT Study Group. Improvement in academic behaviors after successful treatment of convergence insufficiency. Optom Vis Sci. 2012 Jan;89(1):12-8.

Vision and ADHD (1)

Research: possible link between convergence insufficiency and attention deficit disorder (ADHD), the answer to everything?


Convergence is the inward movement that both eyes make when, for example, we are approaching an object close to the eyes. Both eyes should be looking at the same location in space.

Convergence insufficiency is a difficulty for the eyes to move more and more near the nose. When convergence is insufficient, the child may suffer from eyestrain or even double vision, depending on the extent of the problem.

In fact, the convergence test is rather simple to administer. Ask the child to look at a target (small penlight or a pencil, for example) which is located at eye level. Approach the target to the eyes, which will be  converging until either 1) the child reports double vision or 2) you can observe that one eye loses fixation and moves outwards. Note the distance at which this occurs. This portion of the test is called the “break point of convergence.” The normal distance is about 5 cm (2 inches). Closer still, the eyes can not converge anymore.

The second part of the test is to measure the “recovery point” of convergence. Once the break point is reached, you simply move the target slowly away from the eyes until you see that both eyes are now fixating the target. The normal distance from the point of recovery is about 10 cm (4 inches) (see figure below). Of course, doing the test requires some practice.

We note the test as follows:

Convergence test: 8 cm / 20 cm (break point / recovery point)

Possible link between convergence and ADHD

An article published in the scientific literature in 2005 has created a stir that still persists. We know that the diagnosis of ADD or ADHD is mainly done by questionnaire and that there are no objective tests to make this diagnosis. But in 2005, a research has shown a possible link between convergence insufficiency and attention deficit hyperactivity disorder (ADHD). The beginning of a new era?

A potential relationship between convergence insufficiency and attention deficit hyperactivity disorder (ADHD) has been uncovered by researchers at the University of California, San Diego. “This is the first report on the potential connection of these two disorders,” Dr. David B. Granet, ophthalmologist [UCSD Shiley Eye Center].

The study “showed that children with convergence insufficiency are three times more likely to be diagnosed with ADHD than children without the disorder.” We will come back to this study and others…

Scientific studies

Now back to the study by Dr. Granet and his team. This study argues that children being evaluated for attention deficit hyperactivity disorder (ADHD) often have an eye exam as part of their evaluation. The symptoms of convergence insufficiency (CI) can make it difficult for a student to concentrate on extended reading and overlap with those of ADHD. Surprising statement from an ophthalmologist when we know that these doctors are rarely concerned with such problems.

A retrospective review of 266 patients with CI presenting to an academic pediatric ophthalmology practice was performed. All patients included were diagnosed with CI by one author and then evaluated for ADHD diagnosis. A computerized review was also performed looking at the converse incidence of CI in patients carrying the diagnosis of ADHD.

Twenty-six patients (9.8%) were diagnosed with ADHD at some time in their clinical course. Of the patients with ADHD and convergence insufficiency, the review of computer records showed a 15.9% incidence of CI in the ADHD population. It would therefore seem to be a three-fold greater incidence of ADHD in patients with convergence insufficiency when compared with the incidence of ADHD in the general US population (1.8-3.3%). The authors also noted a three-fold greater incidence for this convergence problem in the population with ADHD. This may simply represent an association and not be a causal link.

But just before Dr. Granet’s article, a team of optometrists (Borsting et coll., 2005) publihed a research on the same subject a a few months before.

Borsting et al. identified accommodative (focusing) and convergence insufficiency problems in relation to other learning difficulties such as attention deficit hyperactivity disorder (ADHD). The purpose of this study was to evaluate the frequency of ADHD behaviors in school-aged children with symptomatic accommodative dysfunction or convergence insufficiency.

24 children from 8 to 15 years of age with symptomatic accommodative dysfunction or convergence insufficiency were included in this study. One parent of each child completed the Conners Parent Rating Scale-Revised Short Form (CPRS-R:S). The children’s scores on the CPRS-R:S were compared with the normative sample.

Regarding the Conners questionnaire, and more specifically the S, cognitive problem/inattention, hyperactivity, and ADHD indexes were significantly different from normative values (p < or = .001 for all tests).

The results from this preliminary study suggest that school-aged children with symptomatic accommodative dysfunction or convergence insufficiency have a higher frequency of behaviors related to school performance and attention as measured by the Conners questionnaire.

Gronlund et al. in 2007 studied various aspects of visual function in children with attention deficit hyperactivity disorder (ADD / ADHD) and establish whether treatment with stimulants is reflected in functioning of the visual system.

In all, 83% of children had normal visual acuity without treatment, and 90% with the use of stimulants. A problem with eye alignment (phoria) was found in 29% without treatment, and 27% with stimulants. A stereoscopic vision problem (three-dimensional vision) was found in 26% without stimulants, and 27% with stimulants. Abnormal convergence (> 6 cm or no convergence) was noted in 24% without treatment and 17% with treatment. Signs of visual-perceptual problems were found in 21% of all children. Children with AD/HD had a high frequency of visual findings, which were not significantly improved with stimulants.

Visual attention and reading problems

Tackling Dyslexia Before Kids Learn to Read

From: ScienceDaily (Apr. 5, 2012) —

For children with «dyslexia», the trouble begins even before they start reading and for reasons that don’t necessarily reflect other language skills. That’s according to a report published online in Current Biology, a Cell Press publication, that for the first time reveals a causal connection between early problems with visual attention and a later diagnosis of dyslexia.

“Visual attention deficits are surprisingly way more predictive of future reading disorders than are language abilities at the prereading stage,” said Andrea Facoetti of the University of Padua in Italy.

The researchers argue that the discovery not only closes a long-lasting debate on the causes of dyslexia but also opens the way to a new approach for early identification and interventions for the 10 percent of children for whom reading is extremely difficult.

The researchers studied Italian-speaking children for a period of three years, from the time they were prereading kindergarteners until they entered second grade. Facoetti’s team, including Sandro Franceschini, Simone Gori, Milena Ruffino, and Katia Pedrolli, assessed prereaders for visual spatial attention — the ability to filter relevant versus irrelevant information — through tests that asked them to pick out specific symbols amid distractions. The children also took tests on syllable identification, verbal short-term memory, and rapid color naming, followed over the next two years by measures of reading.

Those test results showed that kids who initially had trouble with visual attention were also the ones to later struggle in reading.

“This is a radical change to the theoretical framework explaining dyslexia,” Facoetti said. “It forces us to rewrite what is known about the disorder and to change rehabilitation treatments in order to reduce its impact.”

The author says that simple visual-attention tasks should improve the early identification of children at risk for dyslexia. “Because recent studies show that specific prereading programs can improve reading abilities, children at risk for dyslexia could be treated with preventive remediation programs of visual spatial attention before they learn to read.”