What are the diagnostic changes for Obsessive‑Compulsive Disorder (OCD) across DSM‑III (Diagnostic and Statistical Manual of Mental Disorders, third edition), DSM‑III‑R (Text Revision), DSM‑IV (fourth edition), DSM‑5 (fifth edition), DSM‑5‑TR (Text Revision), ICD‑10 (International Classification of Diseases, tenth revision), and ICD‑11 (eleventh revision)?

Evolution of OCD Diagnostic Criteria Across DSM and ICD Versions

The most significant diagnostic changes for OCD occurred with DSM-5 (2013) and ICD-11, which reclassified OCD from an anxiety disorder into a new standalone category of "Obsessive-Compulsive and Related Disorders" and introduced insight and tic-related specifiers while removing certain restrictive criteria. 1, 2

Major Categorical Reclassification

DSM-III through DSM-IV Era

• OCD was classified as an anxiety disorder throughout DSM-III, DSM-III-R, and DSM-IV, reflecting the historical conceptualization that anxiety was the primary feature 1, 2
• DSM-IV (1994) required that adults recognize their obsessions or compulsions as excessive or unreasonable (Criterion B), which proved problematic for patients with poor insight 3, 4

DSM-5 Revolutionary Changes (2013)

• DSM-5 moved OCD out of the Anxiety Disorders section entirely, creating the new "Obsessive-Compulsive and Related Disorders" chapter 1, 2
• This new category includes OCD, body dysmorphic disorder (previously somatoform), trichotillomania (previously impulse control), plus newly recognized hoarding disorder and excoriation (skin-picking) disorder 1

ICD Evolution

• ICD-10 maintained OCD within anxiety disorders and required a minimum 2-week duration of symptoms 5
• ICD-11 aligned with DSM-5, creating an analogous Obsessive-Compulsive and Related Disorders chapter that also includes Tourette syndrome and hypochondriasis 1

Core Diagnostic Criteria Refinements

Definition of Obsessions and Compulsions

• DSM-5 redefined and clarified obsessions to explicitly include thoughts, images, AND impulses/urges (not just thoughts), recognizing the full spectrum of intrusive mental experiences 2, 5
• Compulsions were clarified as repetitive behaviors OR mental acts (not "stereotyped" behaviors as in ICD-10), performed in response to obsessions or according to rigid rules 1, 5
• DSM-5 explicitly recognizes that avoidance and thought-stopping are important strategies patients use to manage obsessions, beyond just performing compulsions 2

Insight Criterion Changes

• DSM-IV's requirement that adults recognize symptoms as excessive or unreasonable (Criterion B) was deleted in DSM-5 3
• DSM-5 introduced a three-level insight specifier replacing the old "with poor insight" designation: 1
  • With good or fair insight: recognizes OCD beliefs are definitely or probably not true
  • With poor insight: thinks OCD beliefs are probably true
  • With absent insight/delusional beliefs: completely convinced OCD beliefs are true
• This change prevents misdiagnosis of OCD with absent insight as a psychotic disorder, ensuring appropriate treatment rather than inappropriate antipsychotic monotherapy 1, 6
• ICD-11 similarly adopted an insight specifier, replacing ICD-10's less useful specifiers of "predominantly obsessional thoughts," "compulsive acts," or "mixed" 5

Time and Clinical Significance

• DSM-5 maintained that symptoms must be time-consuming (typically >1 hour per day) and cause clinically significant distress or functional impairment 1
• There was consideration in DSM-5 development to adjust what constitutes "time-consuming," though the 1-hour threshold remained 3
• ICD-11 removed the ICD-10 requirement of a minimum 2-week duration, recognizing that OCD can be diagnosed based on symptom severity and impairment rather than arbitrary time thresholds 5

New Specifiers Introduced

Tic-Related Specifier

• DSM-5 added a tic-related specifier for individuals with current or past history of a tic disorder 1, 3
• This reflects growing evidence that OCD with versus without tics differs in phenomenology, psychobiology, and treatment response, with males more likely to have early-onset OCD with comorbid tics 1
• This specifier acknowledges the close relationship between OCD and Tourette syndrome 1

Diagnostic Hierarchy and Exclusion Changes

Comorbidity Recognition

• ICD-11 removed exclusions that previously prevented OCD diagnosis if comorbid with Tourette syndrome, schizophrenia, or depressive disorders 5
• Both DSM-5 and ICD-11 maintain that OCD should not be diagnosed if symptoms are better explained by another mental disorder, but provide extensive differential diagnosis guidance 1
• The diagnostic hierarchy criterion specifies that obsessions/compulsions cannot be attributable to substance effects or another medical condition 1

Medical Exclusion Clarification

• There was consideration in DSM-5 development to clarify what constitutes a "general medical condition" in the exclusion criteria, though the basic principle remained 3

Clinical Features Emphasized

Symptom Dimensions

• While not formal criteria, DSM-5 text emphasizes major symptom dimensions: contamination/cleaning, harm/checking, forbidden thoughts/mental rituals, and symmetry/ordering 1, 7
• These dimensions are stable within individuals over time, with changes typically occurring within rather than across dimensions 1

Ego-Dystonic Nature

• Both DSM-5 and ICD-11 emphasize that obsessions are intrusive, unwanted, and ego-dystonic, causing significant anxiety and distress 7, 8
• This distinguishes OCD from ego-syntonic conditions like Obsessive-Compulsive Personality Disorder 7, 6

Common Diagnostic Pitfalls to Avoid

• Do not misdiagnose OCD with absent insight as schizophrenia—the delusional beliefs in OCD are circumscribed to OCD themes (contamination, harm) without hallucinations, disorganized speech, or negative symptoms 1, 6
• Do not confuse normal developmental rituals or common intrusive thoughts with OCD—diagnosis requires >1 hour daily time consumption plus substantial distress or functional impairment 1, 6
• Recognize that hoarding is now a separate disorder in DSM-5/ICD-11, though hoarding symptoms can occur in some OCD patients 6
• Distinguish OCD from Generalized Anxiety Disorder—GAD worries are about real-life concerns and lack the driven compulsive neutralizing behaviors 6