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Chapter 3 Assessment in Clinical Psychology. Definitions of Assessment. Dictionaries define assessment as an estimate of value or worth. A real estate assessor, for example, looks at a house and estimates its value.
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Definitions of Assessment • Dictionaries define assessment as an estimate of value or worth. A real estate assessor, for example, looks at a house and estimates its value. • Assessment can be defines as “the process of collecting information to be used as the basis for informed decisions by the assessor by those to whom results are communicated”. • The decision – making process, based upon the collection of relevant information, using a formal set of ethical criteria, which contributes to an overall evaluation of a person and his circumstances.
Clinical psychologists collect and process assessment information that is more formal and systematic than that available to nonprofessionals • But because they are still human beings, the quality of their judgments and decisions about clients can be threatened by the same sources of bias and error that affect everyone else.
THE CLINICAL ASSESSMENT PROCESS • Clinical assessment has been described in various ways (Tallent, 1992) • All of them portray it as a process of gathering information to solve a problem • And recognize that, to be most effective, assessment activities should be organized in a sequence of systematic, logically related steps.
Clinical Assessment Process Planning data collection procedures Collection assessment data Data processing hypothesis formation Communicating assessment data
Clinical Assessment Process At each step, clinicians are confronted by important questions For planning data collection Procedures: • How much information about the person is enough? • Which kind of data will be most valuable? • How can inaccurate information be detected and eliminated? • Where should information be sought?
Clinical Assessment Process For data processing hypothesis formation • How should assessment data be combined? • How can the assessor minimize bias when interpreting data? • Might a computer process assessment data more competently than a human being?
Clinical Assessment Process For communicating assessment data • Who should be given access to assessment results and for what purpose? • How will assessment affect those who are assessed? • How can people be protected from misuse or abuse of assessment information?
Planning for Assessment • Two related question must be answered before clinical assessment can begin • What do we want to know?, and • How should we find out about it?
Levels of Assessment & Some Representative Data from Each • Somatic- Blood type, RH factor, autonomic stress response pattern, kidney & liver function, genetic data, basal metabolism, vision, toxicology, neuroimaging data (fMRI, Cat, Pet). • Physical- Ht, wt, sex, eye color, hair color, body type • Demographic- Name, age, address, phone#, occupation, education, income, marital status, # of children.
4.Overt Behavioral- Reading speed, eye-hand coordination, frequency of fighting with others, conversational skill, interpersonal assertiveness, occupational competence, smoking habits. 5. Cognitive- Response to intelligence test items, reports on thoughts, performance on tests of information processing or cognitive complexity, response to tests of reality perception and structuring.
6. Emotional- Reports of feelings, responses to tests measuring mood states, physiological responsiveness. 7. Environmental- Location& characteristics of housing; # & description of cohabitants, job requirements & characteristics; physical & behavioral characteristics of family, friends, & coworkers; nature of specific cultural or subcultural standards & traditions; general economic conditions; geographical location.
The Case Study Guide • The clinician’s plans for exploring particular levels from a rough outline of the assessment task. Ideally, this outline, or case study guide, will be broad enough to provide a general overview of the client. • Yet, focused enough to allow coverage of all the more specific questions that the clinician wishes to address.
Factors Guiding Assessment Choices • Clinicians choices about how attention should be devoted to each assessment level, what questions to ask level, and what assessment techniques to employ are guided not only by their theoretical approach, but also by research on the reliability and validity of the interviews, tests, observation, and life records that serve as the main sources of assessment data in clinical psychology. • Indeed, reliability and validity are the primary criteria by which any assessment instrument should be judged.
Reliability • Reliability refers to consistency in or agreement among assessment data. • It can be evaluated in several ways. • If the results of repeated measurements of the same client are very similar, the assessment procedures are said to have high test-retest reliability • Another way to evaluate reliability is to examine internal consistency.
If data from one part of an assessment such as odd-numbered test items are similar to other part such as the even-numbered items that assessment is said to be internally consistent. This dimension has sometimes been called split-half reliability. • Finally, interrater reliability is measured by comparing the conclusions drawn by different clinicians using a particular assessment system to diagnose, rate, or observe the same client. • The more they agree, the higher the interrater reliability.
Validity • The validity of an assessment method reflects the degreeto which “it measures what it is supposed to measure”. • The content validity of an assessment method is determined by how well it taps all the relevant dimensionsof its target. • Predictive validity is measured by evaluating how well an assessment forecasts events- violent behavior or suicide attempts, for example. • concurrent validity when two assessment devices agree about the measurement of the same quality
Predictive and concurrent validity are subtypes of criterion validity which measures how strongly an assessment result correlates with important independent criteria of interest. • Finally, there is construct validity – an assessment device has good construct validity when its results are shown to be systematically related to the construct it is supposed to be measuring.
The unified validity of any assessment method should be evaluated not only in terms of content, predictive, and concurrent validity, but also in terms of how well the method taps into the mental characteristics and processes of in tersest, whether the construct to be measured has guided the development and scoring of the method, and whether using the method results in decisions about people that are unbiased and beneficial to them in the short-run and the long-run.
Clinician Specific Factors • Clinicians assessment choices are also influenced by personal experiences and preferences. • Clinical psychologists may tend to use, or avoid, particular assessment methods simply because those methods were either emphasized or criticized by faculty in their graduate training program.
Similarly, those who find certain measurement tactics tedious of unrewarding tend to seek answers to assessment questions through other procedures with which they are more comfortable. • These personal factors help explain why some assessment methods continue to be used by some clinicians even when research evidence fails to support their reliability or validity.
THE GOALS OF CLINICAL ASSESSMENT • The major goals of clinical assessment fall into three general categories; diagnostic classification description, and prediction. • Diagnostic Classification • Once clinical psychologists began working with adult clients during and after world War I, they came under the influence of medical personnel, particularly psychiatrists.
Accurate psychodiagnosis is important for several reasons: First, proper treatment decisions often depend on knowing what, exactly, is wrong with a client Second, research into the causes of psychological disorders requires reliable and valid identification of disorders and accurate differentiation of one disorder from another. Finally, classification allows clinicians to efficiently communicate with one another about disorders in a professional "shorthand" (Sartorius et al ,1996).
Alternative Diagnostic Proposal • Called the dimensional approach, avoids the either- or dichotomy by measuring people on a select number of personality dimensions. • Those dimensions might include extroversion, openness to experience, conscientiousness, emotional stability, and agreeableness (the "big five"). • One advantage of the dimensional approach is that it reflects how normality shades into psychopathology rather than imposing an arbitrary boundary between the two
Another is that it allows persons to be described in terms of strengths and weaknesses, correcting what many see as an overemphasis on pathology in current diagnostic procedures. • Other diagnostic proposals call for describing psychopathology in terms of specific theories or contextual principles
Description • For many clinicians today, descriptive assessment is more important than diagnostic classification. • Description-oriented assessment makes it easier for clinicians to pay attention to clients assets and adaptive function, assessment data are used to provide pretreatment measures of clients behavior, to guide treatment planning, and to evaluate changes in behavior after treatment. • Prediction • The third goal of clinical assessment is to make prediction about human behavior.
Predicting Dangerousness • In fact, clinical psychologists find it difficult to predict dangerousness accurately (Monahan, 1988;Borum, 1996). • One reason for this problem is that the base rate, or frequency with which dangerous acts are committed in any group of people is usually very low.
Sources of Assessment Data • Interview Interview mimic ordinary social interactions, thus providing a way of collecting simultaneous samples of a persons verbal and nonverbal behavior. Second, interviews require no special equipment and can take place almost anywhere. Third, the interview is highly flexible. The clinician is free to direct the inquiry to whatever topics and issues might help the assessment process.
Observations "Action speak louder than words" A second advantage of observation is relevance to behaviors of greatest clinical interest. In spit of its advantages, observational assessment is not problem free. As described in chapter 4 the reliability and validity of observation data can be threatened by observer error or bias, inadvertent observer influences on behavior under observation and specific situational factors.
Test • Tests can be easy, economical, and conveniently administered. • Responses to most tests can be translated into scores, test data facilitate communication between professionals about a client. • Finally, test data allow the clinician to compare a clients behavior with that of thousands of other who have taken the some test
Life Records As they pass through life, people leave a paper trail consisting of school, work, police, medical and financial records, letters and diaries, photographs, a wards, and the like.
The Value of Assessment Sources. • Clinical Psychological seldom rely on a single sources of assessment data as they create a working image of a client. • It often takes multiple sources of assessment to separate those who engage in certain behaviors from those who do not engage in them
Processing Assessment Data • After assessment goals are established and data are collected, the clinicians must determine what those data mean. If information is to be useful in reaching the clinicians assessment goals, it will have to be transformed from raw into interpretation and conclusions. • Levels of Clinical Inference • Clinicians’ judgments or inferences can be characterized in terms of their goal, their level of abstraction, or their underlying theoretical approach to clinical psychology.