A psychological assessment is a procedure in which a clinician provides a formal evaluation of an individual’s cognitive, personality, and psychosocial functioning. In Ben’s case, a comprehensive assessment proved valuable in helping to understand the nature of his symptoms and potential directions for treatment.
Clinicians conduct assessments under a variety of conditions. In many cases, clinicians use the assessment process to provide a diagnosis, or at least a tentative diagnosis, of an individual’s psychological disorder. However, clinicians may also use assessments for a variety of other reasons. For example, in forensic assessments, clinicians determine whether a suspect meets the criteria of being competent to stand trial. Clinicians might also provide information that employers can use to evaluate an individual’s appropriateness for a particular job. Assessments are also useful when clinicians consult about an individual’s level of functioning in a specific area. An older woman experiencing memory problems may seek neuropsychological assessment to determine whether she has a cognitive impairment that will require further intervention.
For Ben, the assessment process is critical to understanding the nature of his current symptoms. The clinician must evaluate the potential roles of both brain injury and what may have been the appearance of symptoms unrelated to the train incident. His immediate treatment plan and his long-term psychological development will depend on the outcome of the evaluation. Dr. Tobin provided an initial evaluation, and as a result of this assessment, she decided to refer Ben to a neuropsychologist.
To be useful, clinicians must hold assessments to standards that ensure that they provide the most reproducible and accurate results. The reliability of a test indicates the consistency of the scores it produces. In other words, it should produce the same results regardless of when it is given, and the individual should answer test items in similar fashion. The test’s validity reflects the extent to which a test measures what it is designed to measure. An intelligence test should measure intelligence, not personality. Before using a given test, clinicians should be aware of its reliability and validity, information that is readily available in the published literature about the instrument.
The profession strives to design tests so that the results they produce don’t vary from clinician to clinician. The criterion of standardization clearly specifies a test’s instructions for administration and scoring. Each individual receiving the test should have the same amount of time, and each person scoring the test should do so in the same manner according to the same, predefined criteria. Furthermore, a given score on the test that one person obtains should have a clear meaning. Ideally, the test’s designers have a substantial enough database against which to compare each testtaker’s scores.
In addition to determining a test’s reliability and validity, it is important to take into account its applicability to test-takers from a diversity of backgrounds. Increasingly, test publishers are designing their measures for usage with a variety of individuals in terms of ability level, first language, cultural background, and age. For example, clinicians may need to adapt assessment instruments for use with older adults, who may require larger print, slower timing, or special writing instruments for use with those who have arthritis (Edelstein, Martin, & McKee, 2000). Even so, clinicians need to ensure that they are using the most appropriate instrument for a given client. When interpreting test results, clinicians need to ensure that they don’t fall into the trap of the so-called “Barnum Effect.” Named after legendary circus owner P. T. Barnum, this is the tendency for clinicians unintentionally to make generic and vague statements about their clients that do not specifically characterize the client. Here’s an example of a Barnum Effect statement: “Julia is often shy around other people, but at times she can be very outgoing. When presented with a challenge, she can often perform very well, but she occasionally becomes nervous and intimidated.” These two sentences could apply to Julia, but they could also apply to most other people. Therefore, they don’t say anything special about Julia. Furthermore, most people would find it difficult to disagree with this feedback. You are most likely to encounter the Barnum Effect in situations such as reading your horoscope or a fortune cookie, which are written so generally that they could apply to anyone. These are relatively harmless situations, unless you decide to invest a great deal of money on the basis of such an unreliable prognosticator. In a clinical situation, the problem is that such statements are not particularly insightful or revealing and do not help inform the assessment process.
Clinicians should keep up with the literature to ensure that they are using the best assessment methods possible. Evidence-based assessment includes (1) relying on research findings and scientifically viable theories; (2) using psychometrically strong measures; and (3) empirically evaluating the assessment process (Hunsley & Mash, 2007). By following these guidelines, clinicians ensure that they will evaluate their clients using the most current and appropriate materials available. For example, a seasoned clinician may have a preference for using the assessment methods she learned about in graduate school, but she should be constantly alert for newer procedures that rely on newer technology or research. According to criterion (3), she should also develop evaluation methods to assess whether her assessments are providing useful information about her clients.
For example, consider the case of an assessment suggesting that a client is experiencing significant depressive symptoms even though she seeks help for what she describes as attacks of anxiety. Following the criteria for evidence-based assessment, the clinician would determine whether the tool or tools she used to make the diagnosis provided an accurate characterization of the woman’s symptoms as they evolved over the course of treatment. Similarly, in Ben’s case, the clinician must validate the findings from neuropsychological assessment carefully by obtaining multiple measures to assess possible brain injury.