What are the diagnostic criteria for Obsessive-Compulsive Disorder (OCD) according to the Diagnostic and Statistical Manual of Mental Disorders (DSM)?

DSM-5 Diagnostic Criteria for Obsessive-Compulsive Disorder

OCD is diagnosed when a patient has obsessions and/or compulsions that consume more than 1 hour daily or cause clinically significant distress or functional impairment, and these symptoms are not attributable to substances, medical conditions, or better explained by another mental disorder. 1

Core Diagnostic Requirements

Presence of Obsessions and/or Compulsions

Obsessions are defined by all of the following 2, 1:

• Recurrent and persistent thoughts, urges, or images that are intrusive and unwanted 1
• These cause marked anxiety or distress in most individuals 1
• The individual attempts to ignore, suppress, or neutralize these thoughts with some other thought or action (i.e., performing a compulsion) 1

Compulsions are defined by both of the following 2, 1:

• Repetitive behaviors (hand washing, ordering, checking) or mental acts (praying, counting, repeating words silently) that the person feels driven to perform 1
• These behaviors or mental acts are performed in response to an obsession or according to rules that must be applied rigidly, aimed at preventing/reducing anxiety or distress, but are not realistically connected to what they are designed to neutralize or prevent, or are clearly excessive 1

Clinical Significance Criterion

The obsessions or compulsions must meet both of the following 2, 1:

• Time-consuming: taking more than 1 hour per day 2, 1
• Cause clinically significant distress or impairment in social, occupational, or other important areas of functioning 1

Diagnostic Hierarchy (Exclusion Criteria)

The symptoms must not be 2, 1:

• Attributable to the physiological effects of a substance (drug of abuse or medication) or another medical condition 1
• Better explained by symptoms of another mental disorder 1

DSM-5 Specifiers

Insight Specifiers

The DSM-5 includes three insight levels that must be specified 2, 1:

• With good or fair insight: Individual recognizes OCD beliefs are definitely or probably not true, or may or may not be true 1
• With poor insight: Individual thinks OCD beliefs are probably true 1
• With absent insight/delusional beliefs: Individual is completely convinced OCD beliefs are true 2, 1

Critical pitfall: Individuals with OCD and absent insight are often misdiagnosed as having a psychotic disorder and inappropriately treated with antipsychotics when they actually need OCD-specific treatment. 2, 1

Tic-Related Specifier

• Tic-related specifier: Denotes individuals with a current or past tic disorder 2
• This specifier reflects that patients with OCD with or without tics differ in phenomenology and psychobiology, requiring tailored evaluation and management 2
• Males are more likely to have early-onset OCD (before puberty) and comorbid tics 2, 1

Key Differential Diagnosis Considerations

Normal Intrusive Thoughts vs. OCD

• Intrusive thoughts and repetitive behaviors (thoughts of harming oneself or others, double-checking locks) are common in the general population 2
• Diagnosis requires these thoughts and behaviors to be time-consuming (>1 hour daily) and cause substantial distress or functional impairment 2, 1

Other Obsessive-Compulsive Related Disorders (OCRDs)

• Body dysmorphic disorder, hoarding disorder, trichotillomania, and excoriation disorder all have recurrent thoughts and rituals 2
• The foci of apprehension and form of repetitive behaviors are distinct from OCD in these conditions 2

Anxiety and Mood Disorders

• Worries and ruminations in generalized anxiety disorder and depression are typically about real-life concerns 2, 1
• These tend to be less irrational and ego-dystonic than in OCD 2
• Compulsions are not typically seen in these conditions 2

Psychotic Disorders

• Patients with OCD and poor or absent insight have beliefs that are OCD-related, without the additional features of schizophrenia spectrum disorders 2
• This distinction is critical to avoid inappropriate treatment 1

Assessment Tools

Yale-Brown Obsessive Compulsive Scale (Y-BOCS)

• The Y-BOCS is the gold standard for measuring OCD symptom severity 1
• Scores ≥28 (or ≥14 if only obsessions or only compulsions are present) indicate severe OCD 1
• The scale measures symptom severity independent of the specific content of obsessions or compulsions 3
• A 35% or greater reduction in Y-BOCS scores is considered clinically meaningful treatment response 3

Special Clinical Considerations

Pediatric Presentations

• Young children may not be able to articulate the aims of their behaviors or mental acts 1
• Pediatric autoimmune neuropsychiatric disorders associated with Streptococcus (PANDAS) represents a subtype with sudden onset of obsessive-compulsive symptoms following streptococcal infection 2, 1

Symptom Dimensions

• OCD symptoms fall into a small number of symptom dimensions that tend to remain stable within individuals 2, 1
• Any changes typically occur within symptom dimensions rather than across them 2

Neurological Conditions

• Neurological conditions affecting the basal ganglia (e.g., Sydenham chorea) can present with obsessive-compulsive symptoms and must be ruled out 1