Clinician's Guide To Neuropsychological Assessment

Rodney D. Vanderploeg, Rodney D. Vanderploeg

• Publisher: Psychology Press
• Year: 2014
• ISBN:
  9781135655846
• Edition: 2
• Topic: Psychology
• Subtopic: History & Theory in Psychology
• Index: Psychology

Neuropsychological assessment is a difficult and complicated process. Often, experienced clinicians as well as trainees and students gloss over fundamental problems or fail to consider potential sources of error. Since formal test data on the surface appear unambiguous and objective, they may fall into the habit of overemphasizing tests and their scores and underemphasizing all the factors that affect the validity, reliability, and interpretability of test data. But interpretation is far from straightforward, and a pragmatic application of assessment results requires attention to a multitude of issues. This long-awaited, updated, and greatly expanded second edition of the Clinician's Guide to Neuropsychological Assessment, like the first, focuses on the clinical practice of neuropsychology. Orienting readers to the entire multitude of issues, it guides them step by step through evaluation and helps them avoid common misconceptions, mistakes, and methodological pitfalls. It is divided into three sections: fundamental elements of the assessment process; special issues, settings, and populations; and new approaches and methodologies. The authors, all of whom are actively engaged in the clinical practice of neuropsychological assessment, as well as in teaching and research, do an outstanding job of integrating the academic and the practical. The Clinician's Guide to Neuropsychological Assessment, Second Edition will be welcomed as a text for graduate courses but also as an invaluable hands-on handbook for interns, postdoctoral fellows, and experienced neuropsychologists alike. No other book offers its combination of breadth across batteries and approaches, depth, and practicality.

I

Fundamental Elements of the Assessment Process

CHAPTER ONE

Interview and Testing: The Data Collection Phase of Neuropsychological Evaluations

Rodney D. Vanderploeg

James A. Haley Veterans Hospital, Tampa, Florida, and College of Medicine, University of South Florida

Neuropsychology is the study of brain–behavior relationships and the impact of brain injury or disease on the cognitive, sensorimotor, emotional, and general adaptive capacities of the individual. Its application is primarily carried out in clinical settings in the provision of diagnostic and treatment services. Diagnostic evaluations attempt either to identify the nature or extent of potential injury to the brain when injury is uncertain (e.g., mild head trauma, early dementia, or toxic exposure), or to delineate the behavioral sequelae of brain injury when pathology is known (e.g., stroke, neoplasms, severe head trauma, or advanced dementia).

Since 1970, the clinical assessment of brain–behavior relationships has advanced from the use of single tests of “organicity” to a complex, multifaceted process. Alternative approaches to assessment have been developed. One approach is to utilize carefully constructed, well-validated batteries. Another is to adapt each examination to the specific questions and clinical needs of individual clients. Other approaches lie on a continuum between these. Regardless of the structure of the evaluation, the process neither begins nor ends with testing, (i.e., the administration, scoring, and comparison of test results with cutoff scores or normative data). The competent neuropsychologist interprets evaluation findings and integrates them with historical data, unique aspects of individual performance, and the life situation of each client. The neuropsychological assessment process has multiple stages. The first stage of that process is the gathering of meaningful and interpretable data and is the focus of this chapter.

Multiple issues require the attention of the neuropsychologist within this initial phase. For the purposes of presentation and discussion these have been broken into four general areas: (a) neuropsychological testing versus assessment; (b) clarification of the evaluation and referral questions; (c) the interview, case history, and behavioral observations; and (d) issues of neuropsychological test selection, administration, and session structure. Of course, during the actual evaluation, the neuropsychologist carries out many of these simultaneously, and makes adjustments in approach and methodology as dictated by each client’s unique needs. This chapter identifies assessment principles that can help guide the clinical neuropsychologist. However, competent practice requires the thoughtful consideration of how these assessment issues differentially impact each case. There is no “cookbook” approach.

TESTING VERSUS ASSESSMENT

A psychological test is a sample of behavior obtained under controlled conditions (Maloney & Ward, 1976; Anastasi, 1988). It involves the measurement of differences between individuals, or within the same individual across time, utilizing objective, standardized, and quantified data collection procedures. In and of itself, testing is not capable of answering questions and requires minimal clinical expertise other than the correct administration and scoring of test instruments. Testing is a tool that may be utilized during a neuropsychological assessment as one source of information. However, a proper evaluation ultimately rests on much more than test results.

Psychological assessment differs from testing in purpose, goals, and methodologies (Maloney & Ward, 1976; Matarazzo, 1990). Psychological assessment, or, in this case, neuropsychological assessment, involves a process of solving problems or answering questions. In conducting a neuropsychological assessment, the clinician must first be able to define and clarify the question(s) that need to be answered to meet particular clinical needs. Formulation of the examination questions (and later interpretation of the obtained data; see Chapters 3 and 4) is based in part on knowledge of a variety of content areas. Lezak (1995) suggested that mastery of four areas is essential: (a) clinical psychological practice, (b) psychometrics, (c) neuroanatomy and functional neuroanatomy and (d) neuropathologies and their behavioral effects. A fifth essential knowledge area is a theoretical understanding of how the four content areas just listed interrelate and interact. This latter knowledge area might best be viewed as an overarching model or knowledge of brain–behavior relationships that is applicable across clinical settings and diagnoses.

Once the evaluation questions of interest have been clarified, the neuropsychologist must determine what information needs to be collected and how best to obtain it. Testing would be only one of several evaluation methods that might be utilized. Other methods include the case history, the clinical interview, the mental status examination, behavioral observations, and information from other people who are involved with the client (spouse, children, friends, employer, and other professionals such as nursing staff). If testing is to be conducted, issues of test selection must be competently addressed. Structuring the testing session, administration procedures, and scoring and clerical issues are also important factors in the overall competent completion of the data collection phase of the evaluation process.

Within classical test theory, reliability refers to the consistency of test scores, whereas validity is the extent to which tests assess what they were designed to measure. Apart from factors unique to the test instruments themselves, both reliability and validity can be adversely impacted by population-specific variables (Sattler, 1988). These include factors such as test-taking skill, guessing, misleading or misunderstood instructions, illness, daydreaming, motivation, anxiety, performance speed, examiner–examinee rapport, physical handicaps, and distractibility. Although psychometric issues are addressed in greater detail in chapter 8, it is important to be cognizant of data-collection variables that can adversely impact the reliability and validity of data and how to address these issues in the assessment process.

THE NATURE AND PURPOSE OF THE EVALUATION: CLARIFYING THE EVALUATION QUESTION(S)

Neuropsychological evaluations traditionally have been undertaken for three reasons: diagnosis, client care, and research (Lezak, 1995). Given the nature of the current text, assessments for research purposes are not discussed. Regarding clinical assessments, I strongly believe that a neuropsychological evaluation should not be undertaken unless it is likely to make a relevant difference in a client’s treatment, quality of life, vocational or educational plans, placement/disposition planning, or client/family education or counseling. Helping in the diagnostic process at times certainly falls within this pragmatic framework. Often a correct diagnosis is essential in educating clients, their families, and their treatment staff about prognosis, and in helping to develop a treatment plan. The one exception to this rule would be performing an evaluation for professional training purposes, as long as the client is willing and realizes the potential benefits or lack of benefits that might occur. Table 1.1 lists a variety of common and potentially important reasons for conducting an evaluation.

TABLE 1.1
Potentially Useful Reasons for Conducting a Neuropsychological Evaluation

1. Diagnosis

a. Identifying the presence of a neurological condition

b. Discriminating between behaviorally similar neurological diagnoses

c. Discriminating between neurologic and psychiatric diagnoses

d. Identifying possible neuroanatomic correlates of signs and symptoms

2. Descriptive assessment of cognitive/emotional/psychological strengths and weaknesses

a. Baseline or pretreatment evaluation

b. Posttreatment or follow-up evaluations

3. Treatment planning

a. Rehabilitation treatment planning

b. Vocational planning

c. Educational planning

4. Discharge/placement planning

5. Disability/personal injury determination

6. Competency evaluation

7. Other forensic issues (e.g., diminished capacity)

8. Research

9. Training of others

Requests for evaluation arise from a variety of sources: medical professionals, psychologists or other mental health professionals, various rehabilitation treatment staff, attorneys, clients, and clients’ families. In practice, all too often the relevant clinical questions for the evaluation are unclear, both to the referring professional and to the neuropsychologist. The referral source may be aware that this client appears different from those with whom the source typically works. For example, in a psychiatric setting, the client may exhibit atypical psychiatric symptoms, and “organicity” is suspected. Or, there may simply be a history of an incident that suggests the possibility that a brain injury may have occurred. In medical settings, staff may wonder if the client’s subjective complaints can be objectively verified, or whether symptom patterns can be identified that suggest a particular diagnostic condition. Alternatively, family members may observe some difficulty with memory and suspect dementia. Yet in each case the relevant clinical questions remain somewhat unclear.

The training axiom of clarifying the referral question(s) with the referral source in practice may not be as easy as it sounds. Apart from the obvious problems of the time and energy this requires and the potential unavailability of the referring professional, referral sources may be unclear in their own minds about exactly what they want or need to know. In fact, their clinical questions may change, based in part on the results of the neuropsychological evaluation, yet follow-up evaluation is impractical. Therefore, these additional consultative questions need to be anticipated and addressed at the time of the evaluation, if at all possible.

How then does the neuropsychologist clarify the evaluation question(s)? This, as with the entire evaluation, is a process that will vary across cases and settings. If actual referral questions are asked, a starting point is provided. If not, the referral information furnished likely provides clues. At times it is indeed practical and helpful to talk with the referring professional or with other staff members who work with the client. It is also frequently useful to ask the client and/or the client’s family members about their understanding of why the evaluation was requested and what questions or concerns they have. The history and clinical interview may suggest questions that appear relevant and potentially important. Finally, the observations and results obtained during the evaluation will likely raise questions in the examiner’s mind, the answers to which the referring professional and client may also find useful. By imagining what it is you would want and need to know if you were responsible for the client’s care (or if you were the client), it is possible to develop meaningful evaluation questions and begin to structure a useful evaluation. The neuropsychologist should answer not only the referral questions that were asked, but also those that should have been asked.

For example, a typical referral might be: “Please evaluate this 57-year-old male with complaints of memory problems for the past six months. Client also appears depressed.” This referral suggests the following series of questions:

• Does this man have an amnestic disorder, or is he demented, depressed, or some combination of these conditions?

• Regardless of the underlying diagnosis, does this man have impaired cognitive abilities?

• If cognitively impaired, what is the likely etiology: prior stroke, anoxia, Alzheimer’s disease, Pick’s disease, multi-infarct dementia, psychiatric disorder, or other?

• If demented/impaired, what is the severity of the dementia/impairment?

• If demented, what other cognitive problems exist in addition to memory problems?

• Even if organically impaired, is there a functional component to any identified cognitive difficulties (e.g., depressed and anxious because of a realization of his difficulties)?

• If cognitively impaired, what is the interaction between his personality/psychological characteristics and his impaired cognitive functioning?

• If demented/impaired, what are the implications of the evaluation results for everyday life: ability to work, manage personal finances, live independently, and so on?

• Is this man still competent?

• What recommendations can be offered to help him manage or cope with his cognitive problems?

• What is the prognosis?

• What treatment or life planning recommendations can be offered?

• What education needs to be provided to his family and what recommendations can be offered to them?

INTERVIEW, CASE HISTORY, AND BEHAVIORAL OBSERVATIONS

The Clinical Interview

The clinical interview and behavioral observations occur prior to any test-based assessment. These preliminary, less formal aspects of assessment yield an essential database and qualitative information that may drastically alter the interpretation of subsequent formal test data (Lezak, 1995; Luria, 1980). In fact, they result in the determination of whether it is even possible to pursue formal testing.

For example, a referral is received to rule out dementia on an elderly psychiatric inpatient who is confused, disoriented, has a variable level of arousal, and appears to be hallucinating during the initial interview. Based on this information, it is likely that this client is either delirious, psychotic, or both. The client is not capable of concentrating on or cooperating with standardized testing. Therefore, formal neuropsychological testing is not likely to provide any meaningful data about the nature and extent of any possible underlying dementia. In this case, testing should be rescheduled for after the acute psychosis or delirium has cleared.

The clinical interview is part of the process by which a case history is developed and integrated with presenting complaints and behavioral observations. This information then can be used to help generate hypotheses about the etiologic bases for symptomatology. Such hypotheses, in turn, serve to guide the ongoing interview and the overall evaluation plan. Although such a hypothesis testing approach is an excellent interview strategy, it is important for the clinician to be aware of “confirmatory bias”—that is, the tendency to seek and value evidence in support of a working hypothesis while ignoring or minimizing contradictory evidence (Greenwald, Pratkanis, Leippe, & Baumgardner, 1986). An example is a neuropsychologist who suspects memory problems and consistently probes for subjective complaints and examples, while failing to recognize evidence of intact memory processes. A client’s rich descriptive examples of memory problems are seen as confirmatory, when alternatively they can be viewed as evidence of intact recall of some phenomena that the client is interpreting as memory dysfunction. If the neuropsychologist focuses on evidence consistent with working hypotheses and minimizes contradictory data, then hypotheses will alwa...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Dedication
• Table of Contents
• Preface to the Second Edition
• Part I: Fundamental Elements of the Assessment Process
• Part II: Special Issues, Settings, and Populations
• Part III: Approaches and Methodologies
• Author Index
• Subject Index
• Contributors