Abnormal Psychology

Clinical Diagnosis and Assessment 107

Summary of Diagnosing

Psychological Disorders

Among other purposes, classifi cation systems

for diagnosis allow: (1) patients to be able to

put a name to their experiences and to learn

that they are not alone; (2) clinicians to dis-

tinguish “normal” from “abnormal” psycho-

logical functioning and to group together

similar types of problems; and (3) research-

ers to discover the etiology, course, and suc-

cess of treatments for abnormal psychological

functioning.

Classification systems also have draw-

backs. They can be subject to diagnostic

bias—perhaps on the basis of the patient’s

sex, race, or ethnicity. Classifi cation systems

should be both reliable and valid. Reliability is

less likely when the criteria for disorders are

not clear and when the criteria for different

disorders signifi cantly overlap.

The most commonly used classification

system in the United States is the Diagnostic

and Statistical Manual of Mental Disorders,

presently in its 4th edition, text revision (DSM-

IV-TR). The DSM-IV-TR: (1) generally does not

focus on etiology (the causes of disorders),

but focuses instead on what can be observed

rather than inferred; and (2) lists explicit crite-

ria for each disorder and includes a system for

clinicians and researchers to record diagnoses

as well as additional information that may af-

fect diagnosis, prognosis, and treatment.

DSM-IV-TR has been criticized on numer-

ous grounds, including the subjectivity of some

of the criteria of some disorders, the categori-

cal nature of the classifi cation system, and the

large number of disorders contained in it.

Psychological disorders are primarily diag-

nosed by clinical and counseling psychologists,

psychiatrists, psychiatric nurses, and social

workers. Each type of clinician has received

somewhat different training and therefore may

gather different types of information and use

that information in different ways.

Thinking like a clinician

Your abnormal psychology class watches

a videotape of a clinical interview with Peter, a

man who has been diagnosed with schizophre-

nia. Your professor has been researching new

criteria for diagnosing schizophrenia and has

asked you and your classmates to determine

whether Peter does, in fact, have schizophrenia

according to the new criteria. If you and your

classmates disagree with each other about his

diagnosis, what might that indicate about the

criteria’s reliability and validity, and what might

it indicate about the interview itself?

The professor then asks you to decide

whether Peter has schizophrenia as defi ned by

the DSM-IV-TR criteria. What are some of the

advantages and disadvantages of using DSM-

IV-TR? Based on what you have read, what

factors, other than the specifics of Peter’s

symptoms, might infl uence your assessment?

(Hint: Think of biases.) Should Peter be diag-

nosed with schizophrenia, might there be any

benefi ts to him that come with the diagnosis,

based on what you have read? What might be

the possible disadvantages for Peter of being

diagnosed with schizophrenia? Be specifi c in

your answers.

Summary of Assessing

Psychological Disorders

An assessment may be performed in order to:

(1) obtain additional information for a diag-

nosis, (2) monitor the course of symptoms,

(3) determine what type of treatment might

be most beneficial, or (4) monitor the prog-

ress of treatment. Assessment tools and

techniques must be reliable and valid,

and clinicians should take care to compare

a patient’s assessment data to an appropri-

ate norm for the patient’s background.

Neurological (and other biological) factors

may be assessed with various methods. Neu-

roimaging techniques can assess brain struc-

ture (X-rays, computerized axial tomography,

and magnetic resonance imaging) and brain

function (positron emission tomography and

functional magnetic resonance imaging). Neu-

rotransmitter levels can be assessed through

magnetic resonance spectroscopy, and neu-

rotransmitter and hormone by-products can

be measured in blood, urine, and cerebro-

spinal fluid. Neuropsychological testing can

assess brain functioning.

Various methods are used to assess psy-

chological factors. These include the clinical

interview, observing the patient, the patient’s

self-report, and the reports of others involved

in the patient’s life. Each method has advan-

tages and limitations. Specifi c aspects of psy-

chological functioning can be assessed through

tests of cognitive abilities and personality

functioning can be assessed with inventories,

questionnaires, and projective tests.

Some techniques used to assess psycho-

logical factors can also be used to assess so-

cial factors—such as family functioning—as

well as to provide a more detailed portrait of

the patient’s community and culture. These

social factors affect, and are affected by, neu-

rological and psychological factors.

Thinking like a clinician

Suppose that you have decided to become

a mental health professional. What type of

training (and what type of degree) would you

obtain and why?

Now suppose that you are working in an

emergency room, assessing possible mental

illness in patients. You have been asked to

determine whether a 55-year-old woman, who

was brought in by her son, has a psychological

disorder severe enough for her to be hospital-

ized. Based on what you have read, if you could

use only one assessment method of each type

(neurological, psychological, and social), what

methods would you pick and why?

Key Terms

Diagnosis (p. 73)

Clinical assessment (p. 73)

Diagnostic bias (p. 76)

Reliable (p. 77)

Valid (p. 78)

Prognosis (p. 78)

Prevalence (p. 78)

Comorbidity (p. 79)

Clinical psychologist (p. 86)

Counseling psychologist (p. 86)

Psychiatrist (p. 86)

Psychiatric nurse (p. 87)

Social worker (p. 87)

Computerized axial tomography

(CT) (p. 91)

Magnetic resonance imaging

(MRI) (p. 91)

Positron emission tomography

(PET) (p. 91)

Functional magnetic resonance imaging

(fMRI) (p. 92)

Magnetic resonance spectroscopy

(MRS) (p. 92)

Neuropsychological testing (p. 93)

Clinical interview (p. 94)

Malingering (p. 96)

Factitious disorder (p. 96)

Projective test (p. 100)

More Study Aids

For additional study aids related to this

chapter, go to:

http://www.worthpublishers.com/rosenberg

SUMMING UP

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