Abnormal Psychology

Clinical Diagnosis and Assessment 73

adiagnosis is the identifi cation of the nature of a disorder (American Psychiatric

Association, 2000). A diagnosis is made by assigning a patient’s symptoms to

a specifi c classifi cation. Classifying a set of symptoms as a disorder allows you

to know more than was initially apparent. By analogy, once you’ve categorized

an object as an “apple,” you know that it has seeds inside, can be squeezed to

produce juice or cider, and may have a relationship with the absence of doctors.

Depending on how much is known about a given disorder, a diagnosis may sug-

gest the disorder’s possible causes, its course over time, and its possible treat-

ments. In Rex’s case, for example, a diagnosis for his pattern of drinking and

related behavior would be what mental health clinicians call alcohol dependence

(which we discuss in more detail in Chapter 9). Having a diagnosis might indicate

why he—and other people with the same set of symptoms—may have developed

the disorder and whether the symptoms would be likely to shift in frequency or

intensity over time. Moreover, the diagnosis might indicate that certain types of

treatment, such as those based on behavioral principles (see Chapter 2), might

be more effective than other types of treatment (we will discuss different types of

treatment in detail in Chapter 4).

A diagnosis is based on information about the patient obtained through

interviews, observations, and tests. Such information is part of a clinical

assessment—the process of obtaining relevant information and making a judg-

ment about mental illness based on the information. Clinical assessments often

go further than providing information needed to make a diagnosis. They also

can provide information about the specific ways in which and the degree to

which an individual is impaired, as well as about areas of functioning that are

not impaired. When we discuss the mental health—or mental illness—of Rex

and Rose Mary Walls, we are trying to approximate a clinical assessment based

on the words—and judgments—of their daughter, Jeannette—someone who

knew them intimately. Rex died at the age of 59. Were he alive today and it were

possible to make a clinical assessment of him and Rose Mary, we would be in a

position to determine with greater confi dence whether either of them could be

diagnosed with a psychological disorder.

Diagnosing Psychological Disorders

Rose Mary and Rex Walls created an endurance contest for their growing children.

A typical example was when Lori was diagnosed by the school nurse as severely

near–sighted and in need of glasses. Rose Mary didn’t approve of eyeglasses, com-

menting, “If you had weak eyes... they needed exercise to get strong” (Walls,

2005, p. 96). Rose Mary thought that glasses were like crutches. She herself had

refused to wear glasses for years, and initially refused to get glasses for Lori; she

relented when school offi cials required the glasses for Lori to attend school.

Rose Mary also had entrenched illogical and dysfunctional beliefs about

the importance of keeping land in the family and not selling it under any cir-

cumstance. After Rose Mary’s mother died (when Jeannette was 9 years old),

Rose Mary inherited property in Texas. That property was worth a lot of money

(nearly $1 million), yet she refused to sell it, despite the fact that she and her

children lived in poverty, with no electricity, no indoor plumbing, no heat, and

not enough food.

Rose Mary wasn’t the only parent with unusual beliefs. Rex recounted to his

family that the reason he hadn’t found a job after months of unemployment in a

coal mining town was because the mines were controlled by the unions, which were

controlled by the mob, and he was nationally blackballed after he was kicked out of

the electrician’s union in Arizona (where he had previously worked). In order to get

a job in the mines, he explained, he must help reform the United Mine Workers of

America. And so he claimed that he spent his days investigating that union.

Diagnosis

The identifi cation of the nature of a disorder.

Clinical assessment

The process of obtaining relevant information

and making a judgment about mental illness

based on the information.