Abnormal Psychology

Schizophrenia and Other Psychotic Disorders 533

12.2 • Differential Diagnosis Decision Tree for Psychotic Disorders

Note: NOS stands for “not otherwise specifi ed.” A psychotic disorder NOS is one in which psychotic

symptoms signifi cantly cause distress or impair functioning but do not match the full criteria for

any other disorder in this category.

Source: Adapted from American Psychiatric Association, 2000, Appendix A, pp. 750–751.

Figure 12.2

Symptoms include delusions, hallucinations,

disorganized speech, or grossly disorganized behavior

that is not due to a medical condition or substance use

Yes No

Symptoms of active phase of schizophrenia,

lasting at least 1 month

Psychotic

disorder

NOS

Delusional

disorder

Nonbizarre

delusions

lasting at least

1 month

Brief

psychotic

disorder

Psychotic

disorder

NOS

Delusions

only with

episodes

Functioning

adequately

except for

delusions

Major depressive episode

or manic episode plus

symptoms of active phase

of schizophrenia

Delusions and/or

hallucinations at least

2 weeks long with

no mood symptoms

6 months’

duration

Yes

Yes No

No

Schizo-

affective

disorder

Mood

disorder with

psychotic

features

Schizo-

phrenia

Schizo-

phreniform

disorder

Mood episodes

brief relative

to delusions

Lasting more

than 1 day

but less than

1 month

Yes No Yes No

Yes No Yes No

Yes No

Psychotic

disorder

NOS

Yes No

Mood

disorder

with

psychotic

features