Diagnostic Testing

By Warren Jordan,2014-06-14 16:14
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Diagnostic Testing

     Diagnostic Testing

     Children with developmental disorders are referred routinely to specialists and other clinicians for diagnostic testing. Diagnostic tests and other clinical evaluations help to determine the nature, scope, and intensity of

    each child’s unique abilities and deficits. This section will explore the types of diagnostic testing recommended for children with autism spectrum disorders.

    As stated in the Practice Parameter for the Screening and Diagnosis of Autism, “Although educators, parents,

    and other health care professionals identify signs and symptoms characteristic of autism, a clinician experienced in the diagnosis and treatment of autism is usually necessary for accurate and appropriate diagnosis.”

    Diagnostic testing for Autism Spectrum disorders is not a one-time procedure; it is a complex process.

    The practice parameter outlines the following types of evaluations:

    ; Surveillance and screening

    (See Screening Guidelines)

    ; Diagnosis

    It is recommended that the formal diagnosis of autism is made by a physician or clinician who has

    extensive experience with, or specializes in, Autism Spectrum Disorders, such as a pediatric neurologist, a

    developmental pediatrician, a child psychologist or child psychiatrist. See Specialists for more


    ; Medical and neurologic evaluation

    This includes “a perinatal and developmental history” as well as a “physical and neurologic examination.”

    This can be performed by an experienced physician, a developmental pediatrician, or a pediatric


    ; Evaluation and monitoring of autism

    As part of a team or multidisciplinary approach, specialists are called upon to evaluate and monitor a child

    after diagnosis. See Specialists for more information.

    ; Speech, language, and communication evaluation

    A comprehensive speech-language-communication evaluation should be performed on all children who

    fail language developmental screening procedures. These evaluations should be conducted by an

    experienced speech-language pathologist.

    ; Cognitive and adaptive behavior evaluations

    Tests such as the Vineland Adaptive Behavior Scales and the Scales of Independent Behavior “should be

    performed in all children with autism by a psychologist or other trained professional.” These evaluations

    “provide an overall index of ability” including social, verbal, and non-verbal skills.

    ; Sensorimotor and occupational therapy evaluations

    Depending on the presenting needs of a child, a physical therapist or occupational therapist may assess a

    range of skills, including: fine motor, gross motor, and sensory processing. For children thought to have

    sensory integrative dysfunction, the Sensory Integration and Praxis tests may be required.

    ; Neuropsychological, behavioral, and academic assessments

    These assessments may be performed by a psychologist or other experienced clinician. A child’s behavior,

    cognitive abilities, and social skills are core elements of these evaluations. An “assessment of family

    resources” is also important in order to determine if additional supports or resources may be needed.

    Screening Guidelines

     The following screening guidelines for children under 36 months outline a seven-step process for

    1physicians to use when monitoring healthy development:

    1. Make clinical observations and chart developmental milestones

    2. Conduct routine developmental screening and surveillance

    If concerns are raised:

    3. Refer to Early Intervention AND to specialist for further developmental evaluation

    4. Conduct lead screening

    5. Perform formal audiological assessment

    6. Conduct autism screening.

    If additional concerns are raised:

    7. Refer for formal diagnostic testing

    The first three years of life are crucial to a child’s development. During this period of early development,

    children make regular visits to the physician. Well visits provide important opportunities to record history, observe the child, and monitor the child’s developmental progress over time. First Signs, Inc., in collaboration with our clinical advisory board, has outlined a seven-step process. The following guidelines, adapted from key

    policy statements of the American Academy of Pediatrics and American Academy of Neurology (Practice

    1Parameter) , were developed in order to establish standard practices amongst physicians, to simplify the screening process, and to ensure that all children receive routine and appropriate screenings and timely interventions.

    These recommended guidelines, presented graphically below, are critical to ensuring that young children stay on a healthy developmental path.

Screening Guidelines

    1. General observations and developmental milestones. First Signs recommends that physicians take a brief

    moment at the start of each well visit to observe how the child behaves, interacts, and communicates with a parent or caregiver in either the reception area or examining room. Use the developmental milestone wall chart

    in your First Signs Screening Kit to refer to the social, emotional, and communication milestones for a child’s age and discuss the child’s development with the child’s parents or caregivers. Since it is often difficult to pick up the subtleties of atypical development in a busy practice, measurement through a highly validated

    developmental screening tool is recommended as the most efficient and effective way to monitor a child’s development.

    2. Routine developmental screening. First Signs recommends that a physician, nurse practitioner, or certified

    physician assistant perform routine developmental screenings using a highly validated screening tool at each well visit on all children from birth through school age to identify those at risk for atypical development. A

    screening can give physicians the opportunity to share a child’s developmental strengths and challenges with parents and work with the family to get that child on the correct developmental path. There are a variety of

    ways that practitioners can integrate a developmental screening into a well visit. A parent can complete the screening form in the physician’s waiting room, at home before a well visit, or with the assistance of a nurse, physician, or other professional in the examination room in less than 10 minutes.

    All screening tools vary with respect to targeted age range, accuracy, ease of use, completion time, languages available, and cost. Some developmental screening tools are more specific to social and communication

    milestones, and some are more specific to gross and fine motor skills, while others are more specific to behavior and temperament. All screening tools have limitations and should not take the place of good clinical history and observations. Conversely, clinical history and observations should not take the place of a good screening. Whenever developmental screenings produce concerns, it is essential that physicians refer children for further evaluation, whether or not their own clinical observations agree with the outcome.

    There are several validated screening tools that can be used for routine developmental screening. First Signs has

    included a sample of a well-validated and brief, easy-to-use developmental screening tools in the First Signs

    Screening Kit. See the Screening Kit or Screening Tools for more information. There, you will find supporting

    data, including validity and standardization norms, references to peer-reviewed publications, information about

    2ease of use for clinicians and parents, languages available, and costs.

    If concerns are raised:

    3. Refer to Early Intervention and to specialist for further developmental evaluation. When a developmental

    screening indicates a possible delay, First Signs recommends that you refer the child to Early Intervention and

    directly to a specialist (i.e., developmental pediatrician, pediatric neurologist, psychiatrist, or psychologist) for further developmental evaluation. (See the PDF version of the First Signs brochure “A Pediatric Practitioner's

    Guide: Referring a Child to Early Intervention” a) outside panels, b) inside panels.

    4. Lead screening. Developmental delays and behavioral problems can be a sign of lead poisoning. A child who mouths many objects, or puts non-food items in the mouth, may be at risk for lead poisoning. Because of

    the range of risks involved, lead screenings are performed routinely when a child shows signs of a

    developmental delay or disorder. First Signs recommends that this screening be conducted immediately to rule out lead poisoning and, if detected, to minimize the negative effects of lead exposure. If elevated lead levels are

    found, refer the child to a local health department. Additionally, you may want to refer the child for other

    medical screenings or sub-specialty evaluations to rule out other conditions, since other factors can contribute to high lead levels.

    5. Formal audiological assessment. The relationship between a child’s hearing, communication, and overall development is complex: a child who appears to have a developmental delay may, in fact, have a hearing impairment. A child with a hearing impairment that goes undiagnosed may experience resulting delays in

    development and communication. A child with a communication or developmental disorder may also have related issues with sensitivity to sound. When addressing concerns about a child, First Signs recommends that a

    developmental screening be followed by formal audiological testing.

    6. Autism screening. If a routine developmental screening raises concerns, First Signs recommends that you

    automatically follow up with an autism screening. A parent can complete the autism screening form in the

    physician’s waiting room or with the assistance of a nurse, physician, or other professional in the examination room in less than five minutes.

    Most autism screening tools are designed to detect autism spectrum disorders, concentrating on social and

    communication impairment in children and focusing on DSM IV criteria for autism. They all vary with respect to validated age at which the tool should be administered, accuracy, and languages available. All autism screening tools have limitations, most notably in the lack of well-validated screening tools available for

    children 18 months of age and younger.

    A sample of a well-validated and brief, easy-to-use autism screening tool is included in the First Signs

    Screening Kit, or see Screening Tools for more information, including supporting data such as validity and standardization norms, references to peer reviewed publications, information on ease of use for both health care

    2providers and caregivers, languages available, and costs..

    If additional concerns are raised:

    7. Formal diagnostic evaluation. If an autism screening raises concernsor for a child 18 months and

    younger, there are concerns raised from the history and observationsFirst Signs recommends that you refer

    the child to a developmental pediatrician, pediatric neurologist, psychiatrist, psychologist, or an autism

    specialty team for a formal diagnostic evaluation right away. This clinician should specialize in evaluating children with autism spectrum disorders.

    These recommended guidelines are critical for ensuring that young children stay on a healthy development

    path. Pediatric practitioners play an important role in guiding children and families to favorable developmental outcomes.

    1 Screening Guidelines were compiled and adapted from the following sources: American Academy of Pediatrics. (2001). Committee on Children with Disabilities. Policy Statement: The pediatrician’s role in the diagnosis and management of autistic spectrum disorders in children, Pediatrics, 107, 1221-1226; American Academy of Pediatrics. (2001). Committee

    on Children with Disabilities. Technical Report: The pediatrician’s role in the diagnosis and management of autistic

    spectrum disorders of children, Pediatrics, 107. Filipek, P.A., et al. Practice parameter: Screening and diagnosis of

    autism. Neurology 2000, 55: 468-79. These guidelines are endorsed by the American Academy of Neurology and the American

    Academy of Pediatrics.

    2 To keep pediatric professionals informed, First Signs will follow the development of new and improved screening tools

    as they are introduced, tested, and normed on large populations of children. This information will be published on the First Signs Web site.


     Specialists can play a key role in the diagnosis of, and treatment for, developmental disorders. Parents and physicians should seek input from specialists as part of a “team approach” or a “multidisciplinary approach” that draws on special expertise and is geared to the unique needs of each child.

    In a medical practice, physicians routinely refer children to specialists because the nature or severity of a condition requires special expertise. Similarly, many children with developmental disorders benefit from referrals to specialists with experience in the diagnosis and treatment of these conditions. Each developmental

    disorder has multiple, and variable, impacts on a child. These impacts are best assessed and addressed by a

    range of clinicians and caregivers, working together in a team approach. This approach, also known as a “multidisciplinary approach,” is built on the core concept that each participant, whether parent, physician, or

    other clinician, adds a new dimension of understanding and expertise.

    In the case of children with autism spectrum disorders, the Practice Parameter for the Screening and Diagnosis

    of Autism recommends “a comprehensive multidisciplinary approach,” which can include one or more of the following professionals:

    ; psychologists

    ; neurologists

    ; pediatricians

    ; developmental pediatricians

    ; child psychiatrists

    ; speech-language pathologists

    ; occupational therapists

    ; physical therapists

    ; audiologists

    ; educators

    ; special educators

    ; social workers

    The composition of the “team” is contingent on the presenting needs of the child. Through observation, evaluation, and study, physicians and parents can work together to identify the unique needs of each child. Accordingly, any specialists involved and treatments implemented should be determined by those unique needs.

    More detailed information about each of these specialties can be found in our guest column, “Putting together

    your child’s treatment team,” by author and parent Mitzi Waltz.

    Parents and physicians seeking information about area specialists can contact the local office of the ARC, a

    national organization “of and for people with mental retardation and related developmental disabilities and their families.”

    A parent of a child with an autism spectrum disorder notes, “It is a team approach. It’s the parents, it’s the doctors, it’s the therapists all working together. You know the goal, to get the child to be better than he is


    Autistic Spectrum Disorders: Best Practice Guidelines for Screening, Diagnosis and Assessment

Section I - Core Concepts That Guide Screening, Diagnosis and Assessment

    Major advancements in the sciences of early identification and treatment of ASD have increased public awareness and focused more attention on this class of neurodevelopmental disorders. The core concepts that follow provide guidance for all professionals in the state of California who are responsible for the screening, diagnostic evaluation and/or assessment for intervention planning for persons with ASD. These core concepts suggest a common language by which both professionals and parents can communicate with each other. Importantly, they also provide referring parties with information about what they can expect from well-informed diagnostic and treatment planning teams.

    These Guidelines represent wide collaboration and consensus from expert panels across the state of California regarding screening, evaluation and interdisciplinary assessment for individuals who may meet diagnostic criteria for autistic spectrum disorder. Variables considered by the panels in developing these Guidelines included current scientific knowledge, level of expertise needed to execute a particular function, pragmatics of clinical practice and respect for the family ecology.

    ; The DSM-IV is the current classification standard for establishing a diagnosis of ASD.

The Diagnostic and Statistical Manual, 4th edition (DSM-IV) and the Diagnostic and Statistical Manual, 4th edition, Text

    Revision (DSM-IV, TR) published by the American Psychiatric Association (1994 and 2000) are the current standards for the diagnosis and classification of ASD. In clinical practice, the DSM-IV is a tool to inform clinical judgment. Its use

    requires specialized training that provides a body of knowledge and clinical skills (American Psychiatric Association, 1994). Derivation of a differential diagnosis between the ASD and other alternative psychiatric or developmental disorders should employ the DSM-IV criteria for analysis and clarification of diagnostic impressions.

    ; Early identification is essential for early therapeutic intervention and leads to a higher quality of life for the child and family.

    Numerous studies on early intervention outcome have delineated the

    benefits of early identification and intervention for children with developmental disabilities and, particularly, for those with

    difficulties on the autistic spectrum (Dawson & Osterling, 1997; Harris & Delmolino, 2002; Smith, 1999; Committee on Educational Interventions for Children with Autism, 2001). Strong empirical support exists for the benefits of intensive behavioral programs for young children with autistic spectrum disorders, although the precise teaching strategies and curricula content are often a topic of debate (Dawson & Osterling, 1997; Gresham & MacMillan, 1998; Lovaas, 1987; Ozonoff & Cathcart, 1998; Rogers, 1998; Sheinkopf & Siegel, 1998). While the components of intervention programs are often a source of controversy, it is generally agreed that program intensity combined with early diagnosis and intervention can lead to substantial improvement in child functioning (Harris, 1994b; Sheinkopf & Siegel, 1998).

    A substantial benefit of early intervention is the positive impact on the family's ability to interact in a developmentally appropriate manner with their child and to have a greater understanding of the disability and how it interacts with family life (Committee on Children with Disabilities, 1994). Early identification and diagnosis enhances the opportunity for effective educational and behavioral intervention; reduction of family stress by giving the family specific techniques and direction; and access to medical and other supports (Cox, Klein & Charman, 1999). In the end, early intervention improves the quality of life for the individual and his/her family, and is cost efficient for the human service delivery system

    (Jacobson, Mulick & Green, 1998).

    ; Informed clinical judgment is a required element of a screening, diagnostic and assessment process that leads to accurate identification of and intervention planning for ASD.

    In the absence of a single biomedical marker, simple laboratory test or procedure for identifying children who meet the diagnostic criteria for one of the ASD, accurate identification of individuals with ASD is entirely dependent on clinical competencies. For the diagnosis of ASD, the knowledge base must include familiarity and experience with the research literature and with children with ASD. Clinical judgment, based upon knowledge and experience with this population, is critical to the interpretation of DSM-IV criteria for ASD. Access to professionals who possess the necessary levels of clinical competency, such as pediatricians and psychologists, can be found in private health systems, state funded regional centers, and university medical centers.

    ; The screening, diagnosis and assessment of ASD presents different challenges through the individual's life span.

    While the core impairments in individuals with autistic disorder are commonly identified in early childhood, other spectrum disorders (PDD-NOS, Asperger's disorder) may be identified much later. Although identification of an ASD is usually made during childhood, it is important to recognize that ASD is a lifelong disability that compromises the individual's adaptive functioning from childhood through adulthood to variable extents, and requires different forms of intervention throughout the lifespan. Assessment should never be viewed as a discrete process, but rather as ongoing, flexible and responsive to changes in the individual's profile caused by intervention effects, maturation, family dynamics and other factors.

    ; Practitioners must be aware of and understand confidentiality issues and honor the need for shared information.

    Th[e] Guidelines encourage the use of interdisciplinary teams and interagency collaboration in the screening/early identification, diagnostic evaluation and assessment of individuals suspected of having an ASD. Th[e] Guidelines also

    recognize that "open" oral and written exchange of information among clinicians and agencies places a grave ethical and legal responsibility on those professionals to share only personal information that is clinically pertinent to the purposes of the intervention. A fully informed written consent at each step in the process is not only an ethical responsibility but a legal one as well. The scope of information shared should be decided on a "need to know" basis. For example, the education system might need specific information from the diagnostic and assessment team about a child's learning strengths and challenges. However, family history regarding psychiatric or other health illness that may be important to the diagnostic process should be held in confidence and not automatically shared with the educational planning team without specific consent. Such discretion can be difficult to manage when parents, for example, are asked to sign multiple releases of confidential information with many providers.

    ; Accurate diagnostic evaluation and assessment requires collaboration and problem solving among professionals, service agencies and families.

    Th[e] Guidelines promote interdisciplinary, interagency collaboration and partnership between the referred individual, their family and the service delivery system. It is critical that service providers promote collaboration across disciplines, agencies and programs to resolve conflicts of legal mandates.

    Collaborative efforts should be made to avoid duplication of effort and maximize efficient use of time in pursuit of the desired outcomes for the individual and his/her family. Respect for divergent perspectives is necessary to delineate a comprehensive diagnostic profile of children, adolescents and adults with autistic spectrum disorders. Rather than viewing each component of the process as separate, these Guidelines stress establishing linkages among, for example,

    the primary care provider (PCP), the diagnostic and assessment team and educational planning teams. The diagnostic team, in turn, needs to keep the PCP informed by providing feedback and assisting the PCP in working with the family to ensure appropriate referrals for intervention services, transition planning and family support.

    ; An interdisciplinary process is the recommended means for developing a coherent and inclusive profile of the individual with ASD.

    Autistic spectrum disorders affect multiple developmental domains. Therefore, utilizing an interdisciplinary team constitutes best practice for a diagnosis of ASD and is an essential component of the assessment process. An interdisciplinary team is essential for establishing a developmental and psychosocial profile of the child and family to guide intervention planning. Such an approach promotes seamless communication among team members and leads to a more integrated, cohesive translation of findings. The interdisciplinary team creates a view of the individual that is detailed, concrete, easily understood and offers realistic recommendations (Klin, Sparrow, Marans, et al., 2000). A quality interdisciplinary process involves shared leadership, respect, integration and coordination among professionals. Team members recognize that their individual contributions inform construction of the overall picture of the child and that their individual interpretations enable formulation of conclusions and recommendations based upon the combined efforts of the team.

    ; From screening through intervention planning, the evaluation process must be

    family-centered and culturally sensitive.

    A family-centered frame of reference reinforces the concept of parents and caregivers as the most knowledgeable source of information about the child, acknowledges that the child is part of a larger family system and sets the stage for ongoing collaboration and communication between professionals and family members. The needs, priorities and resources of the family should be the primary focus and be respectfully considered during each step of screening, diagnostic evaluation and assessment for intervention planning.

    A family-centered frame of reference includes cultural sensitivity and regard for family and community diversity of cultural values, language, religion, education, socio-economic and social-emotional factors that influence coping and conceptualization of the individual with ASD. Maintenance of family involvement should remain at the forefront of interactions in keeping with the concept of family as an equal partner in the diagnostic, assessment and intervention processes.

    ; Timely referral and coordination of evaluation and ongoing assessment enhances outcome.

    The diagnostic and assessment process should proceed in a timely manner to expedite the provision of services to the individual and family. Referring professionals should be familiar with options within the individual's geographic area and serve as the communication bridge with service providers to minimize service delays and duplicative efforts. While a child may receive a diagnosis at a young age, a comprehensive profile of skills and deficits is often not obtained for months (and sometimes years) after diagnosis. This incomplete or absent documentation of skills is problematic for the child, family and community service providers. Parental stress is heightened as parents worry about their child while also spending time and energy trying to arrange for needed intervention services. Timely referral, integration, and coordination of clinical teams and service providers lessens family stress and leads to more streamlined and efficient service delivery.

    ; Rapid developments in the field require regular review of current best practice procedures and up-to-date training.

    Rapid developments in conceptualization, measurement and basic research on ASD require a commitment to periodic review of current best practices. The heterogeneity of behavioral expression in ASD across age and developmental status, combined with rapid increases in clinical research and knowledge about the core features of the disorder, necessitate ongoing education and training opportunities for participating clinicians. Major shifts have occurred in scientific thinking about ASD. The knowledge base in ASD is changing so rapidly that parents and professionals face a daily challenge of keeping abreast of new developments. The challenge is to stay current with new methods of evaluation and treatment, learn about and obtain the latest screening tools, and maintain an awareness of local and regional community resources.


    Autistic Spectrum Disorders: Best Practice Guidelines for Screening, Diagnosis and Assessment

    California Department of Developmental Services: 2002

    The Guidelines, a publication of the California Department of Developmental Services, are intended to provide professionals, policymakers, parents and other

    stakeholders with recommendations based on published research, clinical experience and judgment available about "best practice" for screening, evaluating and

    assessing persons suspected of having ASD. Complete Guidelines can be found at Autistic Spectrum Disorders: Best Practice Guidelines for Screening,

    Diagnosis and Assessment

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