Diagnosing Asperger's Syndrome
Diagnosing Asperger's Syndrome
Diagnosing someone with Asperger's syndrome is a subjective decision that depends on the knowledge and experience of the clinicians, or professionals, who are performing the examination and comparing the individual to other people with the disorder. It is as much art as science, because the cluster of symptoms can be so variable, because so many of the symptoms appear in other disorders or in normal individuals, and because recognition of AS is so new.
Asperger's syndrome was first described by an Austrian psychiatrist, Hans Asperger, in 1944. His description, however, received little attention until 1981, when British psychiatrist Lorna Wing rediscovered his paper and named the disorder Asperger's syndrome in his honor. She had observed children and adults very much like the ones Asperger described and suggested that these people displayed a special kind of autism that needed a name of its own. Her descriptions and conclusions interested other psychiatrists and psychologists, who began identifying the group of symptoms and behaviors in patients of their own. Finally, in 1994 Asperger's syndrome became an official psychiatric diagnosis in the United States.
Asperger's syndrome is a psychological and psychiatric diagnosis, but this does not mean that it is a mental illness, brain damage, “craziness,” mental retardation, or emotional sickness. Rather, the diagnosis is one of learning differences, developmental problems, behavioral difficulties, and brains that seem to work in a way that is nontypical. Professionals arrive at the diagnosis by identifying behaviors that seem to fit the symptoms of AS.
No blood test, no brain scan, no medical or psychological examination of any kind can identify a person with Asperger's syndrome. There is no single characteristic that separates people
Hans Asperger was practicing medicine during the time when Austria was part of Nazi Germany. His paper describing the disorder he discovered was published during the height of World War II, when much of Europe and America rejected anything that seemed to be a part of Nazi thought. That is probably why his findings were lost and ignored for so many years. Asperger, however, was a strong opponent of Nazism. He was particularly disturbed by Nazi eugenics laws. These laws were an effort to purify the human race and eradicate people who were “defective” or not of pure German blood. The Nazis attacked not only Jews but also people perceived to be handicapped, mentally ill, or retarded. They believed in killing any child born with a hereditary disease. Asperger was disgusted by these ideas and bravely argued publicly that education could overcome any possible genetic problems. He did his best to save the children who were patients at his clinic by insisting that unusual traits were not signs of weakness or defects. He said, “Not everything that steps out of line, and thus [is] ‘abnormal’, must necessarily be ‘inferior’.”
Quoted in Tony Attwood, The Complete Guide to Asperger's Syndrome. London and Philadelphia: Jessica Kingsley, 2007, p. 11.
with AS from normal people, autistic people, or people with other disorders. There is no one symptom or impairment that leads to a definite diagnosis of AS. Instead, professionals rely on interviews with the individual and with family members, psychological tests, reports from teachers, and their own previous experience with different psychological disorders to arrive at a diagnosis. They look for a whole constellation of behaviors that point to AS. Some of the characteristics and behaviors must be in evidence to diagnose Asperger's, but none of them prove a person has AS. Clinicians have to use their best judgment to diagnose the condition. And because the diagnosis of AS is so new, few people are skilled at recognizing it. Tony Attwood is an Australian psychologist considered to be one of the foremost experts on Asperger's syndrome today. He explains that the diagnostic process is like a “100-piece jigsaw puzzle.” He says:
Some pieces of the puzzle (or characteristics of Asperger's syndrome) are essential, the corner and edge pieces. When more than 80 pieces are connected, the puzzle is solved and the diagnosis confirmed. None of the characteristics are unique to Asperger's syndrome, however, and a typical child or adult may have perhaps 10 to 20 pieces or characteristics.…The ultimate decision on whether to confirm a diagnosis is based on the clinician's clinical experience, the current diagnostic criteria, and the effect of the unusual profile of abilities on the person's quality of life.11
Diagnostic criteria are standards for labeling someone with a disorder. In the United States these criteria are established by the American Psychiatric Association and published in the Diagnostic and Statistical Manual of Mental Disorders (DSMIV). (Mental means psychological and related to thoughts and feelings, not “crazy.”) Every psychiatrist and psychologist uses the DSM-IV criteria to make a diagnosis, because the standards are agreed to be the best tools so far available for recognizing and naming disorders.
DSM-IV classifies Asperger's syndrome as an autism spectrum disorder. It lists six areas of disability or behaviors that should be present to justify a diagnosis of AS:
- Qualitative impairment in social interaction, as manifested by at least two of the following:
- marked impairments in the use of multiple nonverbal behaviors such as eye-to-eye gaze, facial expression, body postures, and gestures to regulate social interaction
- failure to develop peer relationships appropriate to developmental level [for example, a six-year-old may
not play with other children, but play beside them only, which is more normal for a two-year-old.]
- a lack of spontaneous seeking to share enjoyment, interests, or achievements with other people (e.g., by a lack of showing, bringing, or pointing out objects of interest to other people)
- lack of social or emotional reciprocity [give-and-take]
- Restricted repetitive and stereotyped patterns of behavior, interests, and activities, as manifested by at least one of the following:
- encompassing preoccupation with one or more stereotyped and restricted patterns of interest that is abnormal either in intensity or focus
- apparently inflexible adherence [clinging] to specific, nonfunctional routines or rituals
- stereotyped and repetitive motor mannerisms (e.g., hand or finger flapping or twisting, or complex whole-body movements)
- persistent preoccupation with parts of objects [for example, interest in the wheels of toy cars or the parts of vacuum cleaners]
- The disturbance causes clinically significant impairment in social, occupational, or other important areas of functioning
- There is no clinically significant general delay in language (e.g., single words used by age 2 years, communicative phrases used by age 3 years)
- There is no clinically significant delay in cognitive development [intelligence and learning ability] or in the development of age-appropriate self-help skills, adaptive behavior (other than social interaction), and curiosity about the environment in childhood
- Criteria are not met for another specific Pervasive Developmental Disorder or Schizophrenia [a mental illness]12
In other countries the criteria for diagnosing AS include some different standards (some include motor clumsiness, for example), but in the United States clinicians test for the criteria listed in DSM-IV if they suspect an individual may have AS. Usually a team of several professionals is involved before a diagnosis is made.
The psychiatrist, psychologist, or medical doctor, for example, may interview the individual and look for appropriate eye contact, conversational skills, and typical body language. A psychologist will administer an intelligence test. A speech therapist may test language ability. An occupational therapist checks fine motor skills (skills with small muscles such as in the fingers), as well as self-help skills like dressing oneself or tying shoelaces. A neurologist, a medical doctor specializing in the brain and nervous system, may need to rule out any signs that the individual has other brain disorders and may test for motor clumsiness and awkwardness. An educational specialist may administer tests to see if academic knowledge is age-appropriate.
If the individual is a child, parents will be asked about what age the child spoke his or her first word, spoke in sentences, learned to crawl, and other developmental milestones. If the individual is an adult, he or she might be requested to ask family members for these milestones. In general the evaluator is looking for evidence that the person developed as expected, since normal growth and development is one criterion for AS diagnosis.
Clinicians also perform some tests for empathy, the ability to imagine the thoughts of other people. In this area AS people test as not typical. One test involves a kind of game with dolls. It can be used with anyone suspected of having AS, whether they are children, teens, or adults. First the clinician shows the person two dolls that are named Sally and Anne. As the person watches, Sally is made to put a marble in a basket. Then the clinician takes her out of the room and shuts the door. Next the doll named Anne takes the marble out of the basket and hides it in a box. Now Sally is “allowed” to return to the room. The clinician asks the individual where Sally will look for the marble. Typical people, no matter what their age, say that Sally will look in the basket, because that was the last place she saw it before she left the room. A person with AS, however, might say that Sally will look in the box. A person with AS lacks the empathy to imagine that Sally's experiences are not his or her experiences. Sally did not “see” the marble being moved, even though the person being tested did. Psychiatrist James Robert Brasic explains: “Affected children, adolescents, and adults repeatedly
incorrectly think that Sally will know the location of the marble because they do. Affected individuals do not recognize that Sally's understanding of the placement of the marble is different from theirs because she was absent when it was moved.”13 This kind of mistake happens even in people with superior intelligence because they have such a hard time putting themselves in another person's shoes. It is one of many clinical clues that a diagnosis of AS is justified.
Questions, observations, and tests with dolls are all part of the way that professionals reach a diagnosis of AS, but drawing conclusions from all these methods depends on the skill of the clinician. Different clinicians may interpret the same behaviors in different ways. For example, one professional may believe a person has AS because his or her language skills are normal, but another clinician may diagnose the person with autism because the person was slow to say his or her first words as a baby. Another might believe the person is mentally slow or has trouble following directions because he or she did not understand that Sally could not find the marble.
Asperger's syndrome is often misdiagnosed by professionals who have little experience with the syndrome. In one survey 67 percent of children eventually diagnosed with AS had been diagnosed with another disorder first. About 13 percent of them had received three different diagnoses before being seen by an AS expert. Children are commonly labeled as learning disabled, emotionally disturbed, or mentally ill before the diagnosis of AS is made.
In order to make the diagnosis less subjective and more standardized, some experts have developed questionnaires and interviews that can be scored. In these tests the clinician either answers questions or asks the person being tested or the family to answer questions. Points are assigned according to the way the questions are answered. The points are added up, and a kind of Asperger's score is assigned when the total equals more than a certain number.
In Sweden leading AS expert Christopher Gillberg developed such a standard test in 2001. It is called the Asperger Syndrome Diagnostic Interview (ASDI). The interview is designed to be conducted with a close family member and then scored by the clinician. A family member is chosen, even when the person being diagnosed is an adult, because people with AS often do not recognize the unusual ways they relate to the world. Parents or brothers and sisters usually give more accurate information. The interview consists of twenty questions that cover not only the DSM-IV criteria but also Gillberg's Asperger criteria and the original criteria of Hans Asperger himself. Each question is scored either 1 or 0, for exhibiting the behavior or for its not being present. The ASDI includes twenty questions. Here is a sampling of questions from the interview:
- Does he/she exhibit considerable difficulties interacting with peers? If so, in what way?
- Is there a pattern of interest or a specific interest which takes up so much of his/her time that time for other activities is clearly restricted? If there is, please comment.
- Are there comprehension problems (including misinterpretations of literal/implied meanings)? If so, what kind of problems?
- Is his/her gaze stiff, strange, peculiar, abnormal or odd? If so, please characterize.
- Does he/she make limited use of gestures? If so, please comment.14
Most professionals believe that interviews and questionnaires such as the ASDI are valuable tools for diagnosing AS, but no
one uses a single test all by itself as proof that a person has AS. The questions themselves are still subjective, and the total score still depends on the professional's judgment. None of the tests are 100 percent reliable. (Reliability is a measure of whether the same score can be obtained for the same person either by different clinicians administering the test for the same person or by the same interviewer giving the test multiple times for the same person.) The ASDI, for instance, is reliable most of the time, but not all the time for every person tested.
Validity is another measure of a test's usefulness. It is a measure of a test's accuracy and answers the question of whether the test correctly identifies people with AS and never indicates that someone has AS when he or she does not. Validity for most questionnaires and tests is measured by comparing results to professional diagnoses. So far there is no other measure of validity available. The ASDI is considered valid most of the time, but it can misclassify people as AS or miss someone who is already diagnosed as having the disorder. No AS test is 100 percent valid. Even Gillberg himself warns that the ASDI cannot distinguish between someone with AS and someone with high-functioning autism. Attwood asserts, “There is currently no convincing argument or data that unequivocally confirm that High Functioning Autism and Asperger's syndrome are separate and distinct disorders.”15
Because a completely reliable and valid test for AS does not exist, some professionals wonder whether Asperger's is a real syndrome at all. They argue that not only is AS indistinguishable from high-functioning autism, but sometimes people may just have learning disabilities, ADHD, or psychiatric disorders. Some people are perhaps just odd, unfriendly loners, not individuals with a syndrome.
In 1998 Lorna Wing wrote, “Asperger syndrome and high-functioning autism are not distinct conditions.” Psychiatrist Susan Dickerson Mayes and her colleagues agree with this statement. In 2001 they studied 157 children between the ages of five and fourteen who had been previously diagnosed with an autism spectrum disorder. The team was specifically interested in whether DSM-IV criteria for autism and AS could distinguish among the children and reveal differences in their behaviors. Mayes concluded that there were no valid reasons for diagnosing AS instead of autism. She and her team say:
Children with autism who have relatively mild symptoms and high IQs are variously referred to by different clinicians as having autism, high-functioning autism, mild autism, Asperger's disorder or syndrome, pervasive developmental disorder not otherwise specified, or autistic features. This causes much confusion…[and] certainly has not been proven empirically.16
Mayes did add, however, that her study might have yielded different results if she had looked at older teens and adults. She was not sure if her conclusions applied only to younger children because they are harder to diagnose. Attwood also says that Asperger's cannot be reliably diagnosed in very young children.
Despite the controversy about how to diagnose AS, most professionals and AS experts continue to believe it is a real disorder that can be distinguished from other disorders on the autism spectrum. Since it was first recognized, more and more people have been diagnosed with AS, as well as with other autism spectrum disorders. Many professionals argue that the increase in diagnosis is due to an improved awareness and the ability to identify people with the milder autistic traits. Others say that both autism and AS are overdiagnosed. They suggest that “quirky” or nonconforming children are being labeled unfairly.
Studies of the incidence of autistic spectrum disorders do point to a rising rate in populations. No one knows why this should be so, but both autism and AS seem to be more common now than they were in the past. In the United States, for example, 5,200 students were diagnosed with autism in 1991.
By 2005 that number had risen to more than 192,000. By 2006 the prevalence of autism spectrum disorders was estimated to be 1 out of 166. These statistics might support the idea that both autism and AS are overdiagnosed, but most experts disagree. They point out that it was not until the 1990s that professionals began to recognize milder forms of autism. They remind the doubters that AS was not even a diagnosis until 1994. They explain that as the definition of autistic disorders broadened and changed to include milder autistic traits, it was natural that more people would be diagnosed.
As a matter of fact, many clinicians believe that AS is under-diagnosed. Attwood explains: “It is my clinical opinion that we are currently detecting and diagnosing about 50 percent of children who have Asperger's syndrome. Those who are not referred for a diagnostic assessment of Asperger's syndrome are able to camouflage their difficulties and avoid detection, or a clinician fails to see Asperger's syndrome and focuses on another diagnosis.”17 He estimates that the prevalence of AS is about 1 in 250 children. Since almost all of today's older teens and adults with Asperger's were not identified as having the disorder as children (because the diagnosis is so new), no one is sure about the prevalence in the total population. AutismHelp.org, a general information Web site about autism and related disorders, suggests that as many as 1.5 million Americans may have an autism spectrum disorder.
Whether or not AS is clearly defined, increasing in prevalence, or always diagnosed accurately, the experts continue to search for a better understanding of what AS is and why it happens in the first place.