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Abnormal Psychology PSY404

LESSON 17

EVALUATING SYSTEMS

Reliability

· Reliability refers to the consistency of measurements, including diagnostic decisions.

· One important form of reliability, known as inter-rater reliability, refers to agreement among

clinicians.

Validity

· Validity refers to the meaning or importance of a measurement--in this case, a diagnostic decision.

· Validity is, in a sense, an index of the success that has been achieved in understanding the nature of

a disorder.

· Etiological validity is concerned with factors that contribute to the onset of the disorder.

· Concurrent validity is concerned with the present time and with correlations between the disorder

and other symptoms, circumstances, and test procedures.

· Predictive validity is concerned with the future and with the stability of the problem over time.

· Each time the DSM-IV-TR is revised, new categories are added and old categories are dropped,

presumably because they are not sufficiently useful.

Problems and Limitations of the DSM-IV-TR System

DSM-IV-TR does not classify clinical problems into syndromes in the simplest and most beneficial way.

· One of the important issues involves comorbidity, which is defined as the simultaneous

appearance of two or more disorders in the same person.

· Co morbidity rates are very high for mental disorders as they are defined in the DSM system.

Basic Issues in Assessment

Purposes of Clinical Assessment

· Psychological assessment is the process of collecting and interpreting information that will be

used to understand another person.

· Three primary goals guide most assessment procedures: making predictions, planning treatments,

and evaluating treatments.

· Different assessment procedures are likely to be employed for different purposes.

Assumptions about Consistency of Behavior

· Psychologists must be concerned about the consistency of behavior across time and situations.

· They want to know if they can generalize about the person's behavior in the natural environment

on the basis of the samples of behavior that are obtained in their assessment.

· Psychologists typically seek out more than one source of information when conducting a formal

assessment.( observation, interview, and psychological tests )

· Because we are trying to compose a broad, integrated picture of the person's adjustment, we must

collect information from several sources and then attempt to integrate these data.

· One way of evaluating the possible meaning or importance of this information is to consider the

consistency across sources.

Evaluating the Usefulness of Assessment Procedures

· In the case of assessment procedures, reliability can refer to various types of consistency.

· For example, the consistency of measurements over time is known as testretest reliability.

· The internal consistency of items within a test is known as split-half reliability.

· The validity of an assessment procedure refers to its meaning or importance.

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Abnormal Psychology PSY404

Is the person's score on this test or procedure actually a reflection of the trait or ability that the test

was designed to measure?

And does the score tell us anything useful about the person's behavior in other situations?

In general, the more consistent the information provided by different assessment procedures, the

more valid each procedure is considered to be. Interviews, observational procedures, and

personality tests must be carefully evaluated.

The most useful assessment procedures are likely to vary from one problem to the next.

Assessment procedures that are useful in evaluating the effectiveness of a drug treatment program

for hospitalized depressed patients may be quite different from those used to predict the need for

medication among hyperactive schoolchildren.

Interviews

· The clinical interview is the most commonly used procedure in psychological assessment.

· Most of the categories that are defined in DSM-IV-TR are based on information that can be

collected in an interview.

· Interviews provide an opportunity to ask people for their own descriptions of their problems.

· Interviews also allow clinicians to observe important features of a person's appearance and

nonverbal behavior.

Structured Interviews

· Assessment interviews vary with regard to the amount of structure that is imposed by the clinician.

· Some are relatively open-ended, or nondirective.

· Structured interviews, in which the clinician must ask each patient a specific list of detailed

questions, are frequently employed for collecting information that will be used to make diagnostic

decisions and to rate the extent to which a person is impaired by psychopathology.

· Structured interviews list a series of specific questions that lead to a detailed description of the

person's behavior and experiences.

· Structured interview schedules provide a systematic framework for the collection of important

diagnostic information, but they don't eliminate the need for an experienced clinician

The Mental Status Examination

The mental status examination involves systematic observation of an individual's behavior. This type of

observation occurs when one individual interacts with another. Mental status examination can be structured

and detailed. It covers five categories:

Appearance and behavior

This includes individual's dress, appearance, posture and facial expression e.g. an individual can

be slow, lazy and lethargic. Another individual can be active and agile.

Thought Process

Clinicians listen to patient's talk and they get a good idea of the patient thought process. Is his

talk reality oriented, each idea connected with one another or is it full of fantasy, delusions

hallucinations or is it disjointed speech with no association of ideas e.g. schizophrenia.

Mood and affect

A mental health clinician focuses on mood which is the feeling state of the individual and affect

reflects the emotion. Is the client and his talk depressed or in a hopeless fashion or is it in

optimistic fashion.

Example: is the individual laughing or crying, happy or sad, full of expressions or flat without

expression.

Intellectual Function

This estimates the intelligence of the individual. Is the individual of average intelligence, above

average intelligence or below average intelligence?

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Abnormal Psychology PSY404

Perception of person, place and time.

This refers to, does the individual know, who he is, where he is and what date and what time is

it?

The mental status examination tells us how people think, feel and behave and how these actions might

contribute to explain their problems. So actually, we are doing behavioral assessment of people. This

behavioral assessment is done by using direct observation of an individual's thought, feelings and behavior

in situations or context where the individual is having problems.

Advantages of the Clinical Interview as an Assessment Tool

1. The interviewer can control the interaction and can probe further when necessary. By observing the

patient's nonverbal behavior, the interviewer can try to detect areas of resistance. In that sense, the

validity of the information may be enhanced.

2. An interview can provide a lot of information in a short period of time.

Limitations of the Clinical Interview as an Assessment Tool

1. Some patients may be unable or unwilling to provide a rational account of their problems.

2. People may be reluctant to admit experiences that are embarrassing or frightening.

3. Subjective factors play an important role in the interpretation of information provided in an

interview.

Observational Procedures

· Observational skills play an important part in most assessment procedures.

· Sometimes the things that we observe confirm the person's self-report, and at other times the

person's overt behavior appears to be at odds with what he or she says.

· Observational procedures may be either informal or formal.

· Informal observations are primarily qualitative.

· The clinician observes the person's behavior and the environment in which it occurs without

attempting to record the frequency or intensity of specific responses.

· Although observations are often conducted in the natural environment, there are times when it is

useful to observe the person's behavior in a situation that the psychologist can arrange and control.

Rating Scales

· A rating scale is a procedure in which the observer is asked to make judgments that place the

person somewhere along a dimension.

· Ratings can also be made on the basis of information collected during an interview.

· Rating scales provide abstract descriptions of a person's behavior rather than a specific record of

exactly what the person has done.

These are assessment tools, which are used before the treatment to assess changes in patient's

behavior after the treatment. Brief psychiatric rating scales are usually used and completed by hospital

staff to assess an individual on different constructs related with physical or psychological illness.

Behavioral Coding Systems

· Rather than making judgments about where the person falls on a particular dimension, behavioral

coding systems focus on the frequency of specific behavioral events.

· Some adult clients are able to make records and keep track of their own behavior--a procedure

known as self-monitoring.

Advantages of Observational Methods

· Rating scales are primarily useful as an overall index of symptom severity or functional impairment.

· Behavioral coding systems provide detailed information about the person's behavior in a particular

situation.

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Abnormal Psychology PSY404

Limitations of Observational Methods

Observational procedures can be time-consuming and therefore expensive. Observers can make errors.

People may alter their behavior, either intentionally or unintentionally, when they know that they are being

observed--a phenomenon known as reactivity.

· Observational measures tell us only about the particular situation that was selected to be observed.

· There are some aspects of psychopathology that cannot be observed by anyone other than the

person who has the problem.