528 CHAPTER 12
Undifferentiated Schizophrenia
When someone’s symptoms lead to the diagnosis of schizophrenia but do not
completely match those specifi ed for paranoid, disorganized, or catatonic schizo-
phrenia, the individual will be diagnosed with the subtype undifferentiated
schizophrenia.Residual Schizophrenia
Regardless of the subtype of schizophrenia that someone has, when the positive
(and disorganized) symptoms have subsided but the negative symptoms persist,
the full criteria for schizophrenia are no longer met; the person’s subtype classi-
fi cation changes to residual schizophrenia, which indicates that there is a residue
of (negative) symptoms but the pronounced positive symptoms have faded away.
Residual schizophrenia may also be diagnosed when prominent negative symptoms
are absent but two or more mild positive symptoms, such as odd beliefs that are not
delusional, are present (American Psychiatric Association, 2000). The diagnosis of
residual schizophrenia may apply only during a brief period, for example, during
an individual’s transition from a psychotic state to remission. Sometimes, though, an
individual’s symptoms may be such that the diagnosis of residual schizophrenia is
assigned indefi nitely.Defi cit/Nondefi cit Subtypes
In contrast to the DSM-IV-TR subtypes of schizophrenia, an alternative set of
subtypes is based on the presence or absence of neurocognitive defi cits (Horan
& Blanchard, 2003; Kirkpatrick et al., 1989). The defi cit subtype requires the
presence of severe neurocognitive defi cits in attention, memory, and executive
functioning, as well as the positive and negative symptoms that are manifesta-
tions of these defi cits, such as disorganized speech and behavior and alogia. Such
patients are generally more impaired than are other patients with schizophrenia,
their symptoms are less likely to improve with currently available treatments, and
they have a poorer prognosis.
Thenondefi cit subtype requires the presence of primarily positive symptoms,
such as hallucinations and delusions, in conjunction with relatively intact cognitive
functioning. People with this subtype are generally less impaired, and they have a
better prognosis (McGlashan & Fenton, 1993). Someone with the paranoid subtype
in DSM-IV-TR is considered to have the nondefi cit subtype.Distinguishing Between Schizophrenia
and Other Disorders
Positive or negative symptoms may arise in schizophrenia or in the context of
other disorders. Clinicians and researchers must determine whether the posi-
tive or negative symptoms refl ect schizophrenia, another disorder, or, in some
cases, schizophrenia and another disorder. Let’s examine the other disorders
that have symptoms similar to those of schizophrenia and consider how these
disorders are distinguished from schizophrenia. We will contrast schizophrenia
with mood disorders, substance-related disorders, and a set of various psychotic
disorders—including schizophreniform and brief psychotic disorders, schizoaf-
fective disorder, delusional disorder, shared psychotic disorder, and schizotypal
personality disorder.Psychotic Symptoms in Schizophrenia, Mood Disorders,
and Substance-Related Disorders
Other psychological disorders, most notably mood disorders and substance-related
disorders, may involve symptoms such as hallucinations and delusions. (Mood dis-
orders with psychotic features are discussed in Chapter 6, and substance-induced
hallucinations and delusions are discussed in Chapter 9.) The nature of these psy-
chotic symptoms is usually consistent with the characteristics of the mood disorderUndifferentiated schizophrenia
The subtype of schizophrenia characterized
by symptoms that do not completely match
those specifi ed for the paranoid, disorganized,
or catatonic subtype.