Introduction 7
field. Thereafter, the task force of 28 memb ers was approved in 2007, and appointments of
more than 130 work group members were approved in 2008. More than 400 additional
work group advisors with no voting authority were also approved to participate in the pro-
cess. A clear concept of the next evolutionary stage for the classification of mental disorders
was central to the efforts of the task force an d the work groups. This vision emerged as the
task force and work groups recounted the history of DSM-IV’s classification, its current
strengths and limitations, and strategic directio ns for its revision. An intensive 6-year pro-
cess involved conducting liter ature reviews and secondary an alyses, publishing research
reports in scientific journals, developing dr aft diagnostic criteria, posting preliminary
drafts on the DSM-5 Web site for public comme nt, presenting preliminary findings at pro-
fessional meetings, performing field tr ials, and revising criteria and text. 
Proposals for Revisions 
Proposals for the revision of DSM-5 diagnostic criteria were develo ped by members of the
work groups on the basis of ra tionale, scope of change, expected impact on clinical man-
agement and public health, strength of the su pporting research evidence, overall clarity,
and clinical utility. Proposals encompassed chan ges to diagnostic criteria; the addition of
new disorders, subtypes, an d specifiers; and the deleti on of existing disorders. 
In the proposals for revisions, strengths and weaknesses in the current criteria and no-
sology were first identified. Novel scientific findings over the previous two decades were
considered, leading to the creation of a resear ch plan to assess potential changes through
literature reviews and se condary data analyses. Four princi ples guided the draft revisions: