Psychology › Mental health & disorders › Mental disorders: what they are and how common
The DSM, psychiatry's diagnostic manual (now DSM-5-TR)
DSM-I 1952; DSM-5 2013; DSM-5-TR 2022· Concept
Mixed evidenceSome support; effects smaller or less consistent than once thought.
The American Psychiatric Association's manual that defines mental disorders by symptom checklists, used for diagnosis, research and insurance.
See it on the Psychology map →What it says
DSM-I (1952) listed about 106 diagnoses in psychoanalytic language. DSM-III (1980), led by Robert Spitzer, replaced theory with explicit checklists, such as 'five of nine symptoms for two weeks', so clinicians could agree. Later editions came in 1994, 2013 (DSM-5) and 2022 (DSM-5-TR, which added prolonged grief disorder). Homosexuality was removed in 1973. The WHO's ICD-11 is the global counterpart. Many experts see its categories as agreed conventions built from symptoms, not discovered biological diseases.
Why it matters
A DSM diagnosis affects insurance coverage, drug approvals, school support and court cases, so its definitions shape what counts as illness for millions.
Think of it like
Like a building code: written by committee, revised every so often, essential for consistency, but a negotiated standard rather than a law of nature.
The evidence
Published editions and field trials; DSM-5 field trials found good agreement between clinicians on some diagnoses, such as PTSD, but poor agreement on others, such as generalized anxiety.
Open questions
Whether mental disorders are separate categories or points on continuous dimensions is debated; NIMH and the HiTOP research group are building dimensional alternatives.
Inside this (1)
Connections (2)
▸The DSM, psychiatry's diagnostic manual (now DSM-5-TR) classifies Mental disorders: what they are and how commonWell replicated
The connection
The DSM turns the broad idea of a mental disorder into specific, checkable definitions: required symptoms, how long they last, and how much they impair life. These definitions decide who counts as having a disorder in surveys, trials, insurance claims and courtrooms.
Who showed it and when
Published by the American Psychiatric Association since 1952; DSM-5 (2013) was drafted by expert work groups over about a decade.
The evidence
Prevalence numbers, insurance codes and drug approvals throughout this map rely on DSM or ICD criteria, which are publicly documented.
Open questions
In 2013 then-NIMH director Thomas Insel argued DSM categories lack biological validity; whether better ones are possible is unsettled.
▸Rosenhan's 'On Being Sane in Insane Places' helped spur stricter criteria in The DSM, psychiatry's diagnostic manual (now DSM-5-TR)Mixed evidence
The connection
Rosenhan's study seemed to show that psychiatric diagnosis was arbitrary. Together with surveys showing poor agreement between psychiatrists, it added pressure on the American Psychiatric Association to replace vague descriptions with explicit criteria, which Robert Spitzer delivered in DSM-III in 1980.
Who showed it and when
Science, January 1973; Spitzer, who led the DSM-III task force from 1974, publicly rebutted Rosenhan in 1975.
How solid is it?
Historians and Spitzer's own accounts cite the study as part of the climate, but Spitzer's team was already working on criteria, so its exact influence is debated.
Open questions
If, as Cahalan argues, the study was partly fabricated, a flawed paper helped drive a reform many still consider necessary.