nication and restrictive repetitive behaviors/ interests rather than being distinct disor-
ders. This change is designed to improve the se nsitivity and specificity of the criteria for
the diagnosis of autism spectrum disorder and to identify more focused treatment tar-
gets for the specific impairments identified.
•Streamlined classification of bi polar and depressive disorders.  Bipolar and depres-
sive disorders are the most co mmonly diagnosed conditions in psychiatry. It was there-
fore important to streamline th e presentation of these disorders to enhance both clinical
and educational use. Rather than separating  the definition of ma nic, hypomanic, and
major depressive episodes from the definition of bipolar I disorder, bipolar II disorder,
and major depressive disorder as in the prev ious edition, we included all of the com-
ponent criteria within the respective criteria for each disorder. This approach will facil-
itate bedside diagnosis and treatment of these important disorders. Likewise, the
explanatory notes for differentiating bereav ement and major depres sive disorders will
provide far greater clinical guidance than was previously provided in the simple be-
reavement exclusion criterion. The new specifiers of anxious distress and mixed fea-
tures are now fully described in the narrativ e on specifier variations that accompanies
the criteria for these disorders.
•Restructuring of substance use diso rders for consistency and clarity.  The categories
of substance abuse and substance dependence  have been eliminated and replaced with
an overarching new category of substance use disorders—with the specific substance
used defining the specific disorders. “Depen dence” has been easily confused with the
term “addiction” when, in fa ct, the tolerance and withdrawal that previously defined
dependence are actually very  normal responses to prescr ibed medications that affect
the central nervous system and do not necessar ily indicate the presence of an addiction.