Abnormal Psychology
Fifth Edition
Oltmanns and Emery
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Chapter Four
Classification and Assessment of
Abnormal Behavior
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Chapter Outline
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Basic Issues in Classification
Classifying Abnormal Behavior
Evaluating Classification Systems
Basic Issues in Assessment
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Chapter Outline
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Types of Assessment Procedures
Assessing Psychological Systems
Assessing Social Systems
Assessing Biological Systems
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Overview
• Assessment is the process of gathering
information from a new patient.
• A classification system is a list of various
types of problems and their associated
symptoms.
• Diagnosis refers to the identification or
recognition of a disorder on the basis of its
characteristic symptoms.
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Basic Issues in Classification
• A classification system is used to subdivide
or organize a set of objects.
• Classification systems can be based on
various principles, and their value will
depend primarily on the purpose for which
they were developed.
• Different classification systems are not
necessarily right or wrong; they are simply
more or less useful.
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Basic Issues in Classification
Categories versus Dimensions
• After a category has been defined, an object
is either a member of the category or it is not.
• A categorical approach to classification
assumes that distinctions among members of
different categories are qualitative.
• In other words, the differences reflect a
difference in kind (quality) rather than a
difference in amount (quantity).
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Basic Issues in Classification
Categories versus Dimensions (continued)
• As an alternative, scientists often employ a dimensional
approach to classification—that is, one that describes
the objects of classification in terms of continuous
dimensions.
• Rather than assuming that an object either has or does
not have a particular property, it may be useful to focus
on a specific characteristic and determine how much of
that characteristic the object exhibits.
• This process allows scientists to record subtle
distinctions that would be lost if they were forced to
make all-or-none decisions.
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Basic Issues in Classification
From Description to Theory
• Mental disorders are currently classified on the basis
of their descriptive features or symptoms because
specific causal mechanisms have not yet been
discovered.
• While we may eventually develop a more
sophisticated, theoretically based understanding of
certain disorders, this does not necessarily mean we
will ever know the precise causes of disorders.
• In fact, the most likely explanations for mental
disorders involve complex interactions of
psychological, biological, and social systems.
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Classifying Abnormal Behavior
• We need a classification system for
abnormal behavior for two primary reasons.
• First, a classification system is useful to
clinicians, who must match their clients’
problems with the form of intervention that
is most likely to be effective.
• Second, a classification system must be
used in the search for new knowledge.
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Classifying Abnormal Behavior
Brief Historical Perspective
• Currently, two diagnostic systems for
mental disorders are widely recognized.
• One—the Diagnostic and Statistical
Manual (DSM)—is published by the
American Psychiatric Association.
• The other—the International Classification
of Diseases (ICD)—is published by the
World Health Organization.
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Classifying Abnormal Behavior
Brief Historical Perspective
• During the 1950s and 1960s, psychiatric
classification systems were widely criticized.
• One major criticism focused on the lack of
consistency in diagnostic decisions.
• Renewed interest in the value of psychiatric
classification grew steadily during the 1970s,
culminating in the publication of the third edition
of the DSM in 1980.
• This version of the manual represented a dramatic
departure from previous systems.
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Classifying Abnormal Behavior
The DSM-IV-TR System
• More than 200 specific diagnostic
categories are described in DSM-IV-TR.
• These are arranged under 18 primary
headings.
• The manual lists specific criteria for each
diagnostic category.
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Classifying Abnormal Behavior
The DSM-IV-TR System (continued)
• The DSM-IV-TR employs a multiaxial
classification system; that is, the person is
rated on five separate axes.
• Each axis is concerned with a different
domain of information.
• Two are concerned with diagnostic
categories and the other three provide for
the collection of additional relevant data.
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Classifying Abnormal Behavior
Culture and Classification
• The DSM-IV-TR encourages clinicians to
consider the influence of cultural factors in
both the expression and recognition of
symptoms of mental disorders.
• People express extreme emotions in ways
that are shaped by the traditions of their
families and other social groups to which
they belong.
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Classifying Abnormal Behavior
Culture and Classification (continued)
• The diagnostic manual attempts to sensitize
clinicians to cultural issues by including a glossary
of culture-bound syndromes.
• These are patterns of erratic or unusual thinking
and behavior that have been identified in diverse
societies around the world and do not fit easily
into the other diagnostic categories that are listed
in the main body of DSM-IV-TR.
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Classifying Abnormal Behavior
Culture and Classification (continued)
• Culture-bound syndromes have also been
called idioms of distress.
• In other words, they represent a manner of
expressing negative emotion that is unique
to a particular culture and cannot be easily
translated or understood in terms of its
individual parts.
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Classifying Abnormal Behavior
Culture and Classification (continued)
• One syndrome of this type is a phenomenon
known as ataques de nervios, which has been
observed most extensively among people from
Puerto Rico and other Caribbean countries.
• Descriptions of this experience include four
dimensions, in which the essential theme is
loss of control—an inability to interrupt the
dramatic sequence of emotion and behavior.
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Classifying Abnormal Behavior
Culture and Classification (continued)
• These dimensions include:
1) emotional expressions (an explosion of screaming and
crying, coupled with overwhelming feelings of anxiety,
depression, and anger),
2) bodily sensations (including trembling, heart
palpitations, weakness, fatigue, headache, and
convulsions),
3) actions and behaviors (dramatic, forceful gestures that
include aggression toward others, suicidal thoughts or
gestures, and trouble eating or sleeping), and
4) alterations in consciousness (marked feelings of “not
being one’s usual self,” accompanied by fainting, loss
of consciousness, dizziness, and feelings of being
outside of one’s body).
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Evaluating Classification 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.
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Evaluating Classification Systems
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.
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Evaluating Classification Systems
Validity (continued)
• 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.
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Evaluating Classification Systems
Validity (continued)
• 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.
• Up to the present time, clinicians have been more
willing to include new categories than to drop old
ones.
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Evaluating Classification Systems
Unresolved Questions
• Several important issues will have to be
addressed as more systematic information is
collected about the diagnostic categories in
DSM-IV-TR.
• One fundamental question that applies to every
disorder involves the boundary between normal
and abnormal behavior.
• The definitions that are included in the present
version of the manual are often vague with
regard to this threshold.
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Evaluating Classification Systems
Unresolved Questions (continued)
• Cutoff points for the number of features that
are required for a diagnosis also affect the
boundary between normal and abnormal
behavior.
• The cutoffs listed in DSM-IV-TR were
often chosen with little empirical
justification.
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Evaluating Classification Systems
Unresolved Questions (continued)
• Specific time periods are also used in
the definition of various disorders.
• The length of time is often based on a
relatively arbitrary choice.
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Evaluating Classification Systems
Problems and Limitations of the DSM-IV-TR System
• From an empirical point of view, DSM-IV-TR is
hampered by a number of problems that suggest
that it does not classify clinical problems into
syndromes in the simplest and most beneficial
way.
• One of the thorniest issues involves comorbidity,
which is defined as the simultaneous appearance
of two or more disorders in the same person.
• Comorbidity rates are very high for mental
disorders as they are defined in the DSM system.
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Evaluating Classification Systems
Problems and Limitations of the DSM-IV-TR System
(Continued)
• The comorbidity issue is related to another
limitation of DSM-IV-TR: the failure to make
better use of information regarding the course of
mental disorders over time.
• Unfortunately, most disorders listed in DSM-IVTR are defined largely in terms of snapshots of
symptoms at particular points in time.
• Diagnostic decisions are seldom based on a
comprehensive analysis of the way that a person’s
problems evolve over time.
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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.
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Basic Issues in Assessment
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, or
draw inferences about the person’s behavior in
the natural environment on the basis of the
samples of behavior that are obtained in their
assessment.
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Basic Issues in Assessment
Assumptions About Consistency of Behavior
(continued)
• Psychologists typically seek out more than one source
of information when conducting a formal assessment.
• 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.
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Basic Issues in Assessment
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 test–
retest reliability.
• The internal consistency of items within a
test is known as split-half reliability.
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Basic Issues in Assessment
Evaluating the Usefulness of Assessment
Procedures (continued)
• The validity of an assessment procedure refers to
its meaning or importance.
• 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?
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Basic Issues in Assessment
Evaluating the Usefulness of Assessment
Procedures (continued)
• 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
for cross-cultural validity.
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Types of Assessment Procedures
• 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.
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Assessing Psychological Systems
Interviews
• The clinical interview is the most commonly used
procedure in psychological assessment.
• Most of the categories that are defined in DSMIV-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.
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Assessing Psychological Systems
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.
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Assessing Psychological Systems
Structured Interviews (continued)
• 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.
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Assessing Psychological Systems
Advantages of the Clinical Interview as an
Assessment Tool:
1. The interviewer can control the interaction and
can probe further when necessary.
2. 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.
3. An interview can provide a lot of information in
a short period of time.
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Assessing Psychological Systems
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.
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Assessing Psychological Systems
Limitations of the Clinical Interview as an
Assessment Tool (continued):
4. Information provided by the client is necessarily
filtered through the client’s eyes. It is a
subjective account and may be influenced or
distorted by errors in memory and by selective
perception.
5. Interviewers can influence their clients’ accounts
by the ways in which they phrase their questions
and respond to the clients’ responses.
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Assessing Psychological Systems
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.
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Assessing Psychological Systems
Observational Procedures (continued)
• 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.
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Assessing Psychological Systems
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.
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Assessing Psychological Systems
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.
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Assessing Psychological Systems
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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Assessing Psychological Systems
Limitations of Observational Methods
1. Observational procedures can be timeconsuming and therefore expensive.
2. Observers can make errors.
3. People may alter their behavior, either
intentionally or unintentionally, when they
know that they are being observed—a
phenomenon known as reactivity.
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Assessing Psychological Systems
Limitations of Observational Methods
(continued)
4. Observational measures tell us only about
the particular situation that was selected to
be observed.
5. There are some aspects of
psychopathology that cannot be observed
by anyone other than the person who has
the problem.
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Assessing Psychological Systems
Personality Tests and Self-Report Inventories
• Because of their structure, personality
inventories are sometimes referred to as
“objective tests.”
• They consist of a series of straightforward
statements; the person being tested is typically
required to indicate whether each statement is true
or false in relation to himself or herself.
• Some personality inventories are designed to
identify personality traits in a normal population,
and others focus more specifically on
psychological problems.
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Assessing Psychological Systems
Personality Tests and Self-Report Inventories (continued)
• The most extensively used personality Inventory is
the Minnesota Multiphasic Personality Inventory
(MMPI).
• The inventory was revised several years ago, and
it is currently known as the MMPI-2.
• The MMPI-2 is based on a series of more than 500
statements that cover topics ranging from physical
complaints and psychological states to
occupational preferences and social attitudes.
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Assessing Psychological Systems
Personality Tests and Self-Report
Inventories (continued)
• Scoring of the MMPI-2 is objective.
• After the responses to all questions are
totaled, the person receives a numerical
score on each of 10 clinical scales as well as
four validity scales.
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Assessing Psychological Systems
Personality Tests and Self-Report Inventories (continued)
• Before considering the possible clinical
significance of a person’s MMPI-2 profile, the
psychologist will examine a number of validity
scales, which reflect the patient’s attitude toward
the test and the openness and consistency with
which the questions were answered.
• The L (Lie) Scale is sensitive to unsophisticated
attempts to avoid answering in a frank and honest
manner.
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Assessing Psychological Systems
Personality Tests and Self-Report Inventories
(continued)
• Rather than depending only on their own
experience and clinical judgment, which may be
subject to various sorts of bias and inconsistency,
many clinicians analyze the results of a specific
test on the basis of an explicit set of rules that are
derived from empirical research.
• This is known as an actuarial interpretation.
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Assessing Psychological Systems
Advantages of MMPI-2
1. The MMPI-2 provides information about
the person’s test-taking attitude, which
alerts the clinician to the possibility that
clients are careless, defensive, or
exaggerating their problems.
2. The MMPI-2 covers a wide range of
problems in a direct and efficient manner.
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Assessing Psychological Systems
Advantages of MMPI-2 (continued)
3. Because the MMPI-2 is scored objectively,
the initial description of the person’s
adjustment is not influenced by the
clinician’s subjective impression of the
client.
4. The MMPI-2 can be interpreted in an
actuarial fashion, using extensive banks of
information regarding people who respond
to items in a particular way.
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Assessing Psychological Systems
Limitations of MMPI-2
1. The test is not particularly sensitive to certain
forms of psychopathology, especially those that
have been added with the publication of DSM-III
and DSM-IV-TR.
2. The test depends on the person’s ability to read
and respond to written statements.
3. Specific data are not always available for a
particular profile.
4. Some studies have found that profile types are
not stable over time.
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Assessing Psychological Systems
Other Self-Report Inventories
• Many other questionnaires and checklists have been
developed to collect information about adjustment
problems, including subjective mood states such as
depression and anxiety, patterns of obsessive thinking,
and attitudes about drinking alcohol, eating, and
sexual behavior.
• The format of most self-report inventories is similar to
that employed with objective personality tests like the
MMPI-2.
• The primary difference is the range of topics covered
by the instrument.
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Assessing Psychological Systems
Other Self-Report Inventories (continued)
• Self-report inventories usually don’t include
validity scales, and they may not be standardized
on large samples of normal subjects prior to their
use in a clinical setting.
• Self-report inventories offer many advantages as
supplements to information that is collected during
clinical interviews.
• Self-report inventories can lead to serious
problems if they are used carelessly.
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Assessing Psychological Systems
Projective Personality Tests
• In projective tests, the person is presented
with a series of ambiguous stimuli.
• The best known projective test, introduced
in 1921 by Hermann Rorschach, a Swiss
psychiatrist, is based on the use of inkblots.
• Projective techniques such as the Rorschach
test were originally based on
psychodynamic assumptions about the
nature of personality and psychopathology.
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Assessing Psychological Systems
Projective Personality Tests (continued)
• Considerable emphasis was placed on the
importance of unconscious motivations —
conflicts and impulses of which the person
is largely unaware.
• More recent approaches to the use of
projective tests view the person’s
descriptions of the cards as a sample of his
or her perceptual and cognitive styles.
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Assessing Psychological Systems
Projective Personality Tests (continued)
• The Thematic Apperception Test (TAT)
consists of a series of drawings that depict
human figures in various ambiguous
situations.
• The person is asked to describe the
identities of the people in the cards and to
make up a story about what is happening.
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Assessing Psychological Systems
Advantages of Projective Tests
1. Some people may feel more comfortable talking
in an unstructured situation than they would if
they were required to participate in a structured
interview or to complete the lengthy MMPI.
2. Projective tests can provide an interesting source
of information regarding the person’s unique
view of the world, and they can be a useful
supplement to information obtained with other
assessment tools.
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Assessing Psychological Systems
Advantages of Projective Tests (continued)
3. To whatever extent a person’s
relationships with other people are
governed by unconscious cognitive and
emotional events, projective tests may
provide information that cannot be
obtained through direct interviewing
methods or observational procedures.
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Assessing Psychological Systems
Limitations of Projective Tests
1. Lack of standardization in administration
and scoring is a serious problem.
2. Little information is available on which to
base comparisons to normal adults or
children.
3. Some projective procedures, such as the
Rorschach, can be very time-consuming.
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Assessing Psychological Systems
Limitations of Projective Tests (continued)
4. The reliability of scoring and
interpretation tends to be low.
5. Information regarding the validity of
projective tests is primarily negative.
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Assessing Social Systems
• Many self-report inventories, rating scales, and
behavioral coding systems have been designed for
the assessment of marital relationships and family
systems.
• One popular self-report inventory is the Family
Environment Scale (FES), which is composed of
90 true–false items and was designed to measure
the social characteristics of families.
• Direct observations can also be used to assess the
social climate within a family.
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Assessing Social Systems
• The Family Interaction Coding System
(FICS) was developed by Gerald Patterson
and John Reid to observe interactions
between parents and children in their
homes.
• A trained observer visits the family’s home
and collects information for at least 70
minutes just prior to lunch or dinner.
• Trained raters can achieve high levels of
reliability with the FICS.
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Assessing Social Systems
• In addition, a number of research studies have
demonstrated that it is a valid measure of
aggressive behaviors in children, as well as a
useful way to assess the family context in which
these behaviors occur.
• It can distinguish between the families of children
with antisocial behavior or conduct disorders and
nondisturbed families.
• The main problem with the FICS is that it is
expensive to train observers to use it, and the
process of collecting data is very time-consuming.
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Assessing Biological Systems
Psychophysiological Assessment
• The autonomic nervous system is highly
reactive to environmental events and can
provide useful information about a person’s
internal states, such as emotion.
• Recording procedures have been developed
to measure variables such as respiration
rate, heart rate, and skin conductance.
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Assessing Biological Systems
Psychophysiological Assessment
(continued)
• As the person becomes aroused, activity
levels change in these systems.
• Psychophysiological measures can,
therefore, provide sensitive indices of the
person’s internal state.
• It must be emphasized, however, that all of
these measures do not act together.
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Assessing Biological Systems
Psychophysiological Assessment (continued)
• If several physiological responses are measured at
the same time, they may not all demonstrate the
same strength, or even direction, of response.
• Moreover, physiological measures frequently
disagree with the person’s own subjective report.
• Therefore, as with other assessment procedures,
physiological recordings should be used in
conjunction with other measures.
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Assessing Biological Systems
Advantages of Physiological Procedures
1. Psychophysiological recording procedures
do not depend on self-report and,
therefore, may be less subject to voluntary
control.
2. Some of these measures can be obtained
while the subject is sleeping or while the
subject is actively engaged in some other
activity.
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Assessing Biological Systems
Limitations of Physiological Procedures
1. The recording equipment and electrodes may be
frightening or intimidating to some people.
2. There are generally low correlations between different
autonomic response systems.
3. Physiological reactivity and the stability of
physiological response systems vary from person to
person.
4. Physiological responses can be influenced by many
other factors. Some are person variables, such as age
and medication, as well as psychological factors, such
as being self-conscious or fearing loss of control.
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Assessing Biological Systems
Brain Imaging Techniques
• Precise measures of brain structure can be obtained
with magnetic resonance imaging (MRI).
• In MRI, images are generated using a strong
magnetic field rather than X rays.
• Positron emission tomography (PET) is one
scanning technique that can be used to create
functional brain images.
• This procedure is much more expensive than the
other imaging techniques because it requires a
nuclear cyclotron to produce special radioactive
elements.
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Assessing Biological Systems
Brain Imaging Techniques (continued)
• The newest and most exciting method of imaging
brain functions involves functional MRI (fMRI).
• In fMRI, a series of images is acquired in rapid
succession.
• Small differences in signal intensity from one
image to the next provide a measure of momentto-moment changes in the amount of oxygen in
blood flowing to specific areas of the brain.
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Assessing Biological Systems
Advantages of Brain Imaging Techniques
1. In clinical practice, imaging techniques can
be used to rule out various neurological
conditions that might explain behavioral or
cognitive deficits.
2. Procedures such as fMRI and PET can help
research investigators explore the relation
between brain functions and specific mental
disorders.
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Assessing Biological Systems
Limitations of Brain Imaging Techniques
1. Norms have not been established for any of these
measures.
2. These procedures are relatively expensive—
especially PET scans and fMRI—and some
procedures must be used cautiously because the
patient may be exposed to radioactive
substances.
3. We should not assume that all cognitive
processes, emotional experiences, or mental
disorders are necessarily linked to activity (or the
absence of activity) in a specific area of the
brain.
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