Evaluating and Treating Communication and Cognitive Disorders: Approaches to Referral and Collaboration for Speech-Language Pathology and Clinical Neuropsychology
Diane Paul-Brown and Joseph H. Ricker
About this Document
This technical report regarding approaches to referral and collaboration represents a joint effort by members of the Ad Hoc Joint Committee on Interprofessional Relationships of the American Speech-Language-Hearing Association (ASHA) and Division 40 (Clinical Neuropsychology) of the American Psychological Association (APA). ASHA representatives included Pelagie Beeson, Susan Ellis Weismer, Audrey Holland, Susan Langmore, Lynn Maher, Mark Ylvisaker, and Diane Paul-Brown (ex officio). Alex F. Johnson was the ASHA monitoring vice-president (2000–2002). APA representatives included Kenneth Adams, Sharon Brown, Jill Fischer (chair, 1997–1999), Robin Hanks, Doug Johnson-Greene, Sanford Pederson, Steven Putnam, and Joseph H. Ricker (chair, 2000–2002). The report was prepared by Diane Paul-Brown (ASHA) and Joseph H. Ricker (APA) on behalf of the joint committee. This technical report was approved by ASHA's Executive Board (EB 17-2002) at their 2002 meeting.
The authors gratefully acknowledge the assistance of Carol Caperton in the preparation of this document.
Speech-language pathologists and clinical neuropsychologists engage in areas of distinct and common professional practice. The purpose of this document is to encourage referral and collaboration between speech-language pathologists and clinical neuropsychologists, and to inform referral sources (e.g., physicians, rehabilitation and other health care professionals, educators, case managers) about the roles of both professions. The ultimate goal is improved quality of service for individuals affected by communication and cognitive disorders.
This paper describes the training and credentialing standards for both professions, and the roles of speech-language pathologists and clinical neuropsychologists in the assessment and treatment of individuals with acquired cognitive- communication disorders. Following these descriptions is a discussion on the overlap and divergence between the two professions in the use of tests and measures, as well as areas of treatment specific and unique to each profession. Next is a discussion of the use of norms related to published measures, age, and other demographic factors, and recommendations for collaboration between the professions.
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Speech-language pathology. ASHA certifies individuals in speech-language pathology and audiology. ASHA's Certificates of Clinical Competence (CCC), which are granted in speech-language pathology and in audiology, allow the holder to provide independent clinical services and to supervise the clinical practice of service providers who do not hold certification, student trainees, and support personnel (ASHA, 2000). Applicants for certification in speech-language pathology must meet the four requirements established by ASHA, including specific academic course work, practicum, national examination, and clinical fellowship.
Speech-language pathologists must hold a master's or doctoral degree. The master's degree must be earned from a program accredited by the Council on Academic Accreditation in Audiology and Speech-Language Pathology (CAA). Applicants for certification must have earned at least 75 semester credit hours that reflect a well-integrated program of study dealing with the biological/physical sciences and mathematics; the behavioral and/or social sciences, including normal aspects of human behavior and communication; and the nature, prevention, evaluation, and treatment of speech, language, hearing, and related disorders (ASHA, 2000).
The second requirement is supervised clinical observation and clinical practicum. After sufficient course work has been completed, students are assigned to practica provided by the educational institution or a cooperating program. The student must complete at least 25 hours of clinical observation and 350 hours of supervised clinical practicum involving evaluation and treatment of children and adults with communication disorders. Only direct contact with a client or a client's family in assessment, management, and/or counseling can be counted toward practicum (ASHA, 2000). The practicum supervisor must hold a Certificate of Clinical Competence by ASHA. Applicants for certification also must pass the national examination in speech-language pathology within 2 years of the date of the course work and practicum.
The final certification requirement is the completion of the clinical fellowship. The fellowship consists of at least 36 weeks of full-time professional experience or its part-time equivalent, to be completed within a maximum of 36 consecutive months and within 4 years of the date the academic coursework and practicum were approved by ASHA (ASHA, 2000). The fellowship must be completed under the supervision of an ASHA-certified speech-language pathologist. Requirements for supervision and activities are defined in the Certification and Membership Handbook (ASHA, 2000).
It is important to note that the requirements for ASHA certification may or may not be the same as a state's licensure requirements (ASHA, 2000). State regulatory agencies may be contacted for information on regulation of speech-language pathologists and audiologists. ASHA maintains a list of states that regulate audiology and speech-language pathology practice.
ASHA has a specialty recognition program for professionals with advanced knowledge and skills in certain areas in speech-language pathology. An ASHA-approved specialty recognition program in cognitive-communication currently does not exist. The Academy of Neurologic Communication Disorders and Sciences (ANCDS) offers Board Certification in Neurologic Communication Disorders in adults, children, or both on a voluntary basis. Eligibility is limited to speech-language pathologists who hold ASHA certification or a current state license, have at least 5 years of experience with neurologic communication disorders, and meet a rigorous set of standards.
Clinical neuropsychology. Clinical neuropsychology is a professional and scientific discipline that, broadly defined, deals with brain-behavior relationships (Eubanks, 1997). It can involve both assessment of and intervention for cognitive and emotional disorders in children and adults. Clinical neuropsychology is a recognized specialty within the broader field of professional applications of psychology.
A clinical neuropsychologist holds a doctorate plus a state license to practice as a psychologist. However, there is a great deal of variability in training and credentials in the practice of clinical neuropsychology. Although a few programs train students exclusively in clinical neuropsychology, clinical neuropsychologists in North America are typically trained in clinical, counseling, or school psychology. Subsequent to this training, they are licensed as “psychologists” by their state board. Only one state board (Louisiana) offers a specialty license in clinical neuropsychology; all other states license clinicians only as “psychologists” in a general sense regardless of specialty training (e.g., neuropsychology, psychoanalysis, forensic psychology).
Division 40, the Clinical Neuropsychology Division of the APA, in conjunction with the International Neuropsychological Society (INS), has established a definition and guidelines for training in a report of the INS-Division 40 Task Force (1987; see also Division 40 of the APA, 1989). By this standard, a clinical neuropsychologist is defined as “…a professional psychologist who applies principles of assessment and intervention based on the scientific study of human behavior as it relates to normal and abnormal functioning of the central nervous system. The clinical neuropsychologist is a doctoral-level psychology provider of diagnostic and intervention services who has demonstrated competence in the application of such principles for human welfare…” (Division 40, 1989). The definition suggests several major domains of demonstrated competence:
Successful completion of systematic didactic and experiential training in neuropsychology and neuroscience at a regionally accredited university;
Two or more years of appropriate supervised training applying neuropsychological services in a clinical setting;
Licensing and certification to provide psychological services to the public by laws of the state or province in which he or she practices;
Review by one's peers as a test of these competencies.
Attainment of the ABCN/ABPP Diploma in Clinical Neuropsychology is the clearest evidence of competence as a clinical neuropsychologist, assuring that all of these criteria have been met. The statement reflects the official position of APA's Division of Clinical Neuropsychology, but is not to be construed as contrary or superordinate to the polices of the APA overall.
The American Board of Clinical Neuropsychology (ABCN), the affiliated specialty board of the American Board of Professional Psychology (ABPP), is responsible for the examination for the diploma in clinical neuropsychology. Attainment of the diploma in clinical neuropsychology indicates that a clinical neuropsychologist has had his or her credentials thoroughly reviewed, has undergone a rigorous examination of knowledge and practice by peers, and has been found competent to practice.
In September 1997, a conference of clinical neuropsychological educators and practitioners was assembled to discuss issues related to formal education and training in clinical neuropsychology (Hannay et al., 1998; Houston Conference). Although these standards will almost certainly guide the training of future clinical neuropsychologists, they cannot be retroactively applied to current practitioners. Essentially, the conference presented education and training models for becoming a clinical neuropsychologist, with specific guidelines at graduate, internship, and postdoctoral training levels.
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Speech-language pathology. Speech-language pathologists, in accordance with a Code of Ethics (ASHA, 2001a), diagnose and treat children and adults with speech, spoken and written language, and swallowing disorders, including cognitive-communication disorders. A primary purpose for addressing communication and related disorders is to effect positive measurable and functional change(s) in an individual's communication status in order that he or she may participate as fully as possible in all aspects of life—social, educational, and vocational. Key considerations for treatment include maximizing improvement and/or maintenance of functional communication, evaluation of communication outcomes, and enhancement of quality of life. Speech-language pathologists recognize that communication is always an interactive process, and that the focus of intervention may include training of communication partners (e.g., caregivers, family members, peers, educators, etc.) and modification of communication in schools, workplaces, and other settings.
ASHA has delineated specific roles of speech-language pathologists in the treatment of individuals with cognitive impairment (ASHA, 1987). The Scope of Practice in Speech-Language Pathology (ASHA, 2001b), as it relates to cognitive-communication impairments, states that the practice of speech-language pathology includes:
Providing prevention, screening, consultation, assessment and diagnosis, treatment, intervention, management, counseling, and follow-up for disorders of cognitive aspects of communication (e.g., attention, memory, problem solving, executive functions).
Collaborating in the assessment of central auditory processing disorders and providing intervention where there is evidence of speech, language, and/or other cognitive-communication disorders.
The Preferred Practice Patterns for the Profession of Speech-Language Pathology (ASHA, 1997a) also address the assessment, diagnosis, and treatment of individuals with cognitive-communication disorders. Cognitive-communication assessment is defined as “procedures to assess cognitive-communication impairments, delineating strengths, deficits, contributing factors, and implications for functional communication” (ASHA, 1997a). Assessment of cognitive-communication impairment is expected to “…identify and describe strengths and deficits related to cognitive factors (e.g., attention, memory, and problem solving) and related language components (e.g., semantics and pragmatics)” and “…may result in a diagnosis of a cognitive-communication disorder, recommendations for treatment or follow-up, or referral for other examinations or services” (ASHA, 1997a). Treatment for a patient with a cognitive-communication disorder should result in improved, altered, augmented, or compensated speech, improved oral and written language, and improved cognitive-communication behaviors. Treatment may also lead to recommendations for reassessment or follow-up, or for referral for other examinations or services (ASHA, 1997a). The guiding principles that formed the basis of the Preferred Practice Patterns highlight the functional purpose of communication and the essential role of communication partners.
The practice patterns:
Acknowledge that a primary purpose for addressing communication and related disorders is to effect measurable, functional change(s) in an individual's communication status in order that he or she may participate as fully as possible in all aspects of life — social, educational, and vocational.
Recognize that communication is always an interactive process, and that the focus of intervention should include training of communication partners (e.g., caregivers, family members, peers, educators, etc.).
Consider outcomes including prevention of communication, swallowing, and other related disorders; improvement and/or maintenance of functional communication; and enhancement of the quality of life (ASHA, 1997a).
Clinical neuropsychology. Although clinical neuropsychologists and speech-language pathologists both assess cognition in intact and compromised individuals, clinical neuropsychologists are specifically trained and licensed to formally evaluate and treat mood disturbances and emotional functioning. Being typically trained as clinical, counseling, or school psychologists, clinical neuropsychologists routinely provide intervention in the form of psychotherapy, behavior therapy, or counseling with reference to emotional or behavioral problems. It is important to note that these emotional/behavioral problems may or may not be related to the individual's injury, illness, or most proximal reason for referral.
Clinical neuropsychological and speech-language assessments involve the application of psychometric principles and procedures (i.e., standardized testing, measurement, and structured observation) in the evaluation and treatment of brain-behavior relationships. Clinical neuropsychological assessment can provide a unique and necessary component to the evaluation and rehabilitative treatment of the potential cognitive and emotional dysfunction following stroke, brain tumor, and other types of central neurologic dysfunction.
Traditional medical tests and examinations provide information on gross anatomic structure as aspects of physiology and disease. Because of the psychometric and comprehensive nature of a detailed clinical neuropsychological evaluation, a clinical neuropsychological assessment can assist in identifying and quantifying potential functional effects of central neurologic dysfunction. Such deficits include impairments in attention, language, memory, spatial skills, problem solving, psychomotor abilities, and emotional functioning.
Extensive testing in the acute care setting immediately following the onset or exacerbation of cerebral impairment may be of only minimal benefit given the possibility of delirium, transient aphasia, or significant motoric compromise. Brief, focused testing (followed later with a more comprehensive speech, language, and clinical neuropsychological evaluation), however, can be of benefit in identifying and quantifying residual impairments, as well as in making appropriate recommendations for reducing disability and enhancing functional status and participation. This is important for rehabilitation programming, given the need to identify functional capacities that are available for compensatory strategies, as well as those areas that may need to be targeted for improvement. In many acute care settings, the speech-language pathologist conducts the brief, focused testing. As the patient is able to tolerate more testing, the speech-language pathologist may conduct an extensive speech and language evaluation and recommend a clinical neuropsychological evaluation. Clinical neuropsychological and speech-language evaluations can help in formulating plans for community re-integration following cognitive compromise. Complete evaluation in both professions is also useful in identifying and quantifying areas of improvement, which may be required for certain aspects of re-integration after brain impairment (e.g., re-establishing legal independence following appointment of a guardian). Documentation of improvement is likely to be of comfort to individuals (and to the families of these individuals) who have sustained central neurologic dysfunction. Formal assessment is also useful when formulating individual behavioral management plans, given the fact that such plans rely heavily on an individual's ability to learn and follow directions. Clinical neuropsychological and speech-language assessment can also, in some instances, be used as an index of efficacy for some types of treatment, such as interventions designed to reduce cognitive impairments (which may be one goal of cognitive rehabilitation), as well as to index changes following certain medical interventions (e.g., pharmacotherapy).
In some settings, clinical neuropsychologists and speech-language pathologists may provide services focused on ameliorating acquired cognitive problems. Clinical neuropsychologists and speech-language pathologists may also provide services to assist patients with learning new strategies to compensate for acquired cognitive impairments or to modify tasks and environmental demands to increase successful participation despite ongoing disability. These interventions are provided under a variety of names, such as cognitive rehabilitation, cognitive remediation, neuropsychological rehabilitation, and cognitive retraining. Although in wide use, these approaches vary greatly from facility to facility, and have only recently been subject to more rigorous empirical research (see Ylvisaker, Hanks, & Johnson-Greene, 2002, for a literature review). When considering a referral for such services, it is important to consider the empirical basis for the intervention, the likely improvement in cognition from spontaneous recovery alone, the rationale for the intervention (e.g., retraining vs. teaching compensatory strategies), the effects of practice, and the qualifications and experience of the provider.
Clinical neuropsychologists and speech-language pathologists can also be of assistance in rehabilitation by identifying cognitive and behavioral issues that are of relevance in vocational re-integration, and can also assist clients and employers in identifying and developing realistic workplace accommodations in compliance with the Americans with Disabilities Act.
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Although each discipline has its own measures, both professions use some of the same tests (e.g., Boston Diagnostic Aphasia Examination; Boston Naming Test; Scales of Cognitive Ability for Traumatic Brain Injury; Western Aphasia Battery). Speech-language pathologists and clinical neuropsychologists should attempt to coordinate evaluation so there is no overlap in test selection. The issue of practice effects is directly relevant to this recommendation. Practice effects refer to an improvement in test scores, or even more broadly, a domain of cognition, as a function of exposure to similar (but not identical) tests, paradigms, or strategies. In addition, speech-language pathologists and clinical neuropsychologists should be aware of interventions and their impact on test results. Intervention by a speech-language pathologist may affect the results of a subsequent clinical neuropsychological evaluation (through exposure, practice, test sophistication, or improvement in function). Likewise, a clinical neuropsychological assessment has the potential to similarly affect performance on instruments used by speech-language pathologists. Repeated administration may lead to inflated recovery curves.
Speech-language pathologists and clinical neuropsychologists also should be aware of relevant guidelines for test usage. The Code of Fair Testing Practices in Education (1988) presents standards for educational test developers and users in several areas. In addition, the APA has adopted the Standards for Educational and Psychological Testing (1999). Some test-related issues that arise include the following:
Professionals with a particular license or credential may only purchase some measures. For example, the use of intelligence tests is typically restricted to licensed psychologists.
Some domains of practice for assessment/treatment (e.g., IQ testing, academic achievement testing, and personality testing) may be defined by state rules and laws of practice.
Differences in terminology used by insurers, institutions, and licensing boards may result in ambiguity in who provides given services (e.g., “higher level language disorders” and “cognitive disorders” may refer to the same processes, but the terms may have very different reimbursement implications).
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Mood and emotional disorders. Because clinical neuropsychologists are typically trained as clinical psychologists, they are uniquely qualified to formally assess emotional states and to intervene using applied principles of clinical and experimental psychology. Such approaches include, but are not limited to, psychological testing (including objective and projective approaches), personality assessment, behavior analysis, psychotherapy, behavior modification, and group interventions. Speech-language pathologists also provide input on such areas, and assist with formulating a hypothesis regarding a patient's status, treatment needs, or possible outcomes. Furthermore, it is within the scope of practice for speech-language pathologists to evaluate, diagnose, treat, and counsel patients, family members, educators, employers, and other rehabilitation professionals in adaptive strategies for managing cognitive-communication disorders. Speech-language pathologists also must integrate behavior modification treatment techniques as appropriate for the management of associated problems, such as agitation and self-abusive and combative behaviors. Direct intervention for affective and anxiety disorders falls within the province of a clinical neuropsychologist, possibly teaming with a speech-language pathologist if a communication problem contributes to or is a consequence of the affective or anxiety disorder.
Communication and swallowing disorders. Speech-language pathologists, in addition to caring for individuals with cognitive-communication disorders, also diagnose and treat a wide range of speech (i.e., articulation, fluency, voice), language (i.e., comprehension and production; literacy; phonology, syntax, semantics, and pragmatics), swallowing disorders, or other upper aerodigestive functions (ASHA, 2001b; 2001c). In conjunction with audiologists, they provide some services to individuals with hearing loss and their families/caregivers (e.g., auditory training, speech reading). Speech-language pathologists also provide services to modify or enhance communication performance (e.g., accent modification, transgendered care and improvement of the professional voice, personal/professional communication effectiveness). They provide these services for the full age spectrum, as well as for the full range of severity for these conditions. For example, speech-language pathologists establish augmentative-alternative communication techniques and strategies for individuals with severe communication disabilities, treat individuals with motor speech disorders (e.g., apraxia, dysarthria), with difficulties learning to read and write, and with language problems following strokes or traumatic brain injury (e.g., aphasia, anomia, agraphia, alexia) (ASHA, 2001c). ASHA has developed a wide range of guidelines and delineated knowledge and skills needed for appropriate assessment, diagnosis, and treatment for individuals with cognitive-communication, speech, language, swallowing disorders, and other communication needs (ASHA, 1997b).
Although the purpose of this document is to highlight those opportunities when referral to both professions is warranted, ASHA has available its own referral guidelines specific to referrals to speech-language pathology in the area of cognitive-communication for children and adults (ASHA, 1998; see Appendix A and B). These referral guidelines are not meant to be exclusionary, but rather to provide further delineation of the role of a speech-language pathologist in a treatment team in relation to other professionals.
As important as it is for both speech-language pathologists and clinical neuropsychologists to know their professional limits, it is equally important for referral sources, professional colleagues, and interdisciplinary teams to recognize limits. For example, to a colleague or payer source not familiar with the differences, a speech-language evaluation of higher cognitive-communication functions and a neuropsychological evaluation might appear very similar. It is necessary for each profession to educate consumers about the unique contributions and areas of overlap of speech-language pathology and clinical neuropsychology.
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It is critical that speech-language pathologists and clinical neuropsychologists make every effort to approach cases from “the same page,” both conceptually and practically from a functional perspective. In other words, it may cause unwarranted confusion for patients and their families if one profession views a patient from a strict score-based or numeric cut-off perspective, while another profession views the same patient in the context of the patient's education, life experience, effort, personal goals, and values. Contemporary approaches to speech-language pathology and clinical neuropsychology services stress the value of functional assessment, which “measures the ability to receive and convey messages effectively and independently, regardless of the mode of communication in natural contexts” (Frattali, Thompson, Holland, Wohl, & Ferketic, 1995, p. 12).
Functional assessment also recognizes the need for judicious use of norms (e.g., Heaton, Grant, & Matthews, 1991; Spreen & Strauss, 1998) involving issues such as the determination of baseline status and the interpretation of patients' abilities in light of their education and other experiences. Speech-language pathologists and clinical neuropsychologists must recognize the need to consider age, education, premorbid information, social history, present social context, cultural and linguistic background, and pre-injury vocational status in formulating realistic and functional treatment goals within the bounds of the cognitive disorder.
Speech-language pathologists and clinical neuropsychologists who conduct functional assessment also need to be mindful of other factors that affect the accuracy of an assessment. The World Health Organization definitions underscore the need for assessment to address involvement in daily life activities and social aspects of disability (World Health Organization, 2001). Although there are many available tests and measures, most are normed and standardized on samples of educated, middle-class Caucasians (e.g., Boston Diagnostic Aphasia Examination, Ross Information Processing Assessment). Accurate assessment of speech, language, and cognitive functions on standardized norm-referenced measures may be difficult for culturally and linguistically diverse populations, or with populations who may not have the same level of requisite skills or experiences to perform adequately on tests. Furthermore, unless the clinician maintains an open, objective approach to assessment, there can be a “clash” between clinicians' values and those of the patient and/or family (e.g., not everyone thinks reading is important; not everyone values competitive employment). This is another important reason to focus on the assessment of the patient determined by individualized goals and the culture and context in which that person functions.
Databases for determining test validity are rarely equivalent, and are virtually never identical. For example, a normative group used to establish norms for one particular test may differ dramatically and in clinically meaningful ways from the normative group used for another test. In other words, we know how a given standardization sample performs on one particular test, but we rarely have any data that indicate how these same individuals perform in other domains or on other neuropsychological tests. Therefore, speech-language pathologists and clinical neuropsychologists should consult multiple sources of data for accurate test interpretation.
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Speech-language pathologists and clinical neuropsychologists certainly interact clinically, but they should also interact to a much greater degree regarding professional practice issues. Attempts to separate tests and interventions into two mutually exclusive proprietary domains are destined to fail in the provision of the highest quality of service to the patient. No discipline should dictate or attempt to legislate the practice of another without getting into “restraint of trade” issues. Ultimately, the focus of collaborative efforts must be on the clinical utility of information and how professionals with complementary knowledge and skills can affect functional outcome for patients in a beneficial manner.
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