cultivate relationships that provide protection and sup-
port, and they often defer to others excessively. They
often fail to express anger at or disagreement with oth-
ers for fear of losing their support and love, and they
are prone to being involved in psychologically or
physically abusive relationships. They often have dif-
ficulty making everyday decisions without excessive
advice and reassurance from others, and they look for
others to assume responsibility for major areas of their
lives. They have difficulty initiating projects due to
lack of self-confidence in their judgment or abilities.
They often will volunteer to do things that are unpleas-
ant in order to obtain nurturance from others. They
report feeling uncomfortable or helpless when they
are alone due to an exaggerated fear of being inca-
pable of caring for themselves. When a close relation-
ship ends, they often will seek another relationship
immediately as a source of support. Current estimates
suggest that the prevalence rate of the disorder is 0.5%
in the general population and around 1.5% in an out-
patient psychiatric population. These data conflict
with the DSM-IVassertion that DPD is one of the most
frequently reported personality disorders encountered
in outpatient clinics. Studies on inpatient rates suggest
a higher prevalence rate, between 15% and 25%. DPD
frequently co-occurs with other personality disorders
as well as mood, anxiety, and eating disorders.OObbsseessssiivvee--CCoommppuullssiivvee PPeerrssoonnaalliittyy DDiissoorrddeerr
Individuals with obsessive-compulsive disorder
(OCPD) exhibit a pervasive pattern of perfectionism,
orderliness, and control that interferes with flexibility,
efficiency, task completion, and social interactions.
Such individuals are often driven to maintain mental
and interpersonal control through their preoccupation
with details, lists, schedules, and rules. Their perfec-
tionism interferes with their ability to complete a task
because they believe that they cannot meet their
overly strict standards. Although they are excessively
devoted to work to the exclusion of leisure activities
and friendships, they often are inefficient in work
because they are preoccupied with trivial details. They
tend to be inflexible about matters of morality, ethics,
or values. Behaviorally, they are often described as
stubborn and perfectionist, and they may have diffi-
culty with interpersonal relationships due to their
inflexibility. Although it was previously thought that
OCPD reflected a predisposition for Axis I obsessive-
compulsive disorder, more recent research suggests
that OCPD is more highly comorbid with avoidantpersonality disorder. Prevalence rates in the general
population are estimated to be between 2% and 8%
and between 8% and 9% in an outpatient psychiatric
setting.Categorical Versus
Dimensional Approaches
One of the most controversial topics in psychopathol-
ogy over the past few decades has been the classifica-
tion of personality disorders. The categorical model
(e.g.,DSM) assumes that personality disorders can be
defined by a relatively small number of “disorders” or
“types” that are essentially orthogonal. Each disorder
has a specific set of symptoms and signs, and individ-
uals within each diagnostic category are presumed to
make up a homogeneous group. Dimensional approaches
would replace the categorical classification now in use
with a recognition that mental disorders lie on a con-
tinuum with mildly disturbed and normal behavior
rather than being qualitatively distinct. Personality
disorders, therefore, could be regarded as extreme
variants of common personality characteristics, and per-
sonality disorder symptoms could be described in
terms of relative standing on a number of traits. Person-
ality disorders were first placed on a separate axis in
the DSMin 1980, based primarily on the expert opin-
ions of DSMwork group members and without strong
empirical evidence that these disorders existed with
discrete and distinct clinical features. Later researchers
have argued that the categorical classification approach
of the DSMis inadequate. For example, they point to
high levels of comorbidity; many individuals meet
the diagnostic criteria for more than one personality
disorder or for a personality disorder and an Axis
I disorder. Work continues on the development of
dimensional models (e.g., the five-factor model).
Nonetheless, until a unified system of classification is
developed and agreed on, the categorical system
employed by the DSMwill be the mostly widely-used
by clinicians.Matt C. Zaitchik and Trevor H. BareseSee alsoAntisocial Personality Disorder; PsychopathyFurther Readings
Hare, R. D., Hart, S. D., & Harpur, T. J. (1991). Psychopathy
and the DSM-IVcriteria for antisocial personality
disorder. Journal of Abnormal Psychology, 100,391–398.558 ———Personality DisordersP-Cutler (Encyc)-45463.qxd 11/18/2007 12:43 PM Page 558