Case Lab

Distinguish a documented personality change caused by a medical condition from a long-standing personality disorder.

Recognize medication-induced sexual dysfunction, including the importance of proactively asking about it.

Apply the evidentiary distinction between NCD Due to Unknown Etiology and NCD Due to Multiple Etiologies.

Apply the age-5 minimum criterion distinguishing Other Specified Elimination Disorder from Enuresis.

Recognize Rumination Disorder's effortless, non-purging regurgitation, distinguished from the binge-purge cycle and body-image concerns of Bulimia Nervosa.

Distinguish Bulimia Nervosa's binge-compensate cycle from Binge-Eating Disorder's binge-without-compensation pattern and from Anorexia Nervosa's restriction-driven presentation.

Recognize ARFID's fear-of-aversive-consequences presentation, distinguished from Anorexia Nervosa by the absence of body-image disturbance.

Recognize Substance/Medication-Induced Psychotic Disorder's clear temporal link to a specific exposure, distinguished from Psychotic Disorder Due to Another Medical Condition, which requires a documented underlying illness.

Recognize Disruptive Mood Dysregulation Disorder's required combination of severe outbursts AND persistent between-outburst irritable mood, distinguished from ODD and pediatric bipolar disorder.

Recognize Insomnia Disorder as a distinct, primary sleep complaint with daytime impairment, distinguished from sleep disturbance secondary to Generalized Anxiety Disorder and from stimulant-related sleep disruption.

Recognize Hypersomnolence Disorder's primary excessive sleepiness pattern once obstructive and narcoleptic causes have been ruled out by objective testing.

Recognize Genito-Pelvic Pain/Penetration Disorder's characteristic fear, pain, and involuntary pelvic floor tensing specific to penetration, distinguished from a general reduction in desire.

Distinguish Central Sleep Apnea from Obstructive Sleep Apnea Hypopnea and Sleep-Related Hypoventilation using respiratory effort and CO2 patterns on monitoring.

Recognize Gambling Disorder's behavioral-addiction pattern of impaired control and continued use despite consequences, distinguished from Alcohol Use Disorder and from occasional recreational cannabis use without impairment.

Distinguish Speech Sound Disorder's articulation-based deficit from Language Disorder's deficit in vocabulary and grammar.

Distinguish Female Orgasmic Disorder, where desire and arousal are intact but orgasm remains elusive, from Female Sexual Interest/Arousal Disorder, where interest and arousal themselves are reduced.

Recognize a potentially reversible medical cause of cognitive decline that is distinct from Alzheimer's disease.

Distinguish Unspecified Neurocognitive Disorder (workup not yet done) from NCD Due to Unknown Etiology (thorough workup completed, no cause found) and from delirium.

Use rate of progression to distinguish NCD Due to Prion Disease from the much slower course of NCD Due to Alzheimer's Disease.

Distinguish Schizoid Personality Disorder's genuine indifference to closeness from Avoidant Personality Disorder's fear-driven withdrawal from desired relationships.

Distinguish depression caused directly by a medical condition from a medication-induced or independent depressive episode.

Recognize when PTSD-type symptoms follow an exposure that doesn't meet Criterion A, pointing to Other Specified Trauma- and Stressor-Related Disorder.

Distinguish Delayed Ejaculation, where desire is intact but ejaculation is impaired, from Male Hypoactive Sexual Desire Disorder, where desire itself is deficient.

Distinguish anxiety caused directly by a medical condition from a medication-induced anxiety presentation.

Recognize when a substance use pattern involves a substance outside the ten specifically named classes, warranting the 'Other (or Unknown)' category.

Recognize Disinhibited Social Engagement Disorder's indiscriminate sociability toward unfamiliar adults, distinguished from the general impulsivity of ADHD.

Recognize a genuinely mixed personality-disorder presentation as an example of Other Specified Personality Disorder.

Distinguish mania caused directly by a medical condition from mania caused by a medication used to treat that condition.

Distinguish Childhood-Onset Fluency Disorder (Stuttering) from Social Anxiety Disorder by whether disfluency occurs even in private, low-pressure speech.

Apply the 6-month duration criterion distinguishing Other Specified Gender Dysphoria from Gender Dysphoria in Children.

Apply the duration threshold that distinguishes Provisional Tic Disorder from Persistent (Chronic) Motor or Vocal Tic Disorder.

Distinguish Obsessive-Compulsive Personality Disorder's ego-syntonic perfectionism from Obsessive-Compulsive Disorder's ego-dystonic, anxiety-driven obsessions and compulsions.

Apply the 4-day minimum duration criterion distinguishing Other Specified Bipolar Disorder from Bipolar II Disorder.

Recognize identity disturbance due to prolonged coercive persuasion as a recognized example of Other Specified Dissociative Disorder.

Distinguish severe, medication-induced insomnia from primary Insomnia Disorder.

Recognize that psychiatric symptoms often precede motor and cognitive decline in NCD Due to Huntington's Disease, distinguishing it from a primary depressive episode.

Recognize Reactive Attachment Disorder's withdrawn attachment pattern arising from a documented history of insufficient care, distinguished from Autism Spectrum Disorder.

Distinguish Intellectual Disability -- deficits in both intellectual and adaptive functioning with onset during the developmental period -- from Borderline Intellectual Functioning, which involves similar but less severe and non-impairing difficulty.

Recognize limited-symptom panic-like attacks as a recognized example of Other Specified Anxiety Disorder.

Recognize Frontotemporal Neurocognitive Disorder's behavior-first presentation, distinguished from Alzheimer's-type NCD's memory-first pattern.

Distinguish Female Sexual Interest/Arousal Disorder's broad reduction in desire and arousal from Genito-Pelvic Pain/Penetration Disorder's pain- and fear-specific avoidance of penetration.

Distinguish depressive symptoms caused by a medication's known depressogenic effect from an independent major depressive episode.

Recognize the timing and pharmacological evidence needed to diagnose a substance/medication-induced mood disorder rather than an independent bipolar disorder.

Distinguish Other Specified Depressive Disorder (reason documented) from Unspecified Depressive Disorder (insufficient information) and Major Depressive Disorder.

Recognize when uncertainty about a manic/hypomanic history, not just depressive severity, justifies Unspecified Mood Disorder over Unspecified Depressive Disorder.

Recognize a medical-condition-caused psychiatric presentation, and distinguish it from the reversed causal direction of Psychological Factors Affecting Other Medical Conditions.

Recognize body-focused repetitive behavior disorder as a recognized example of Other Specified OCD and Related Disorder.

Recognize when a brief-duration sexual difficulty with a possible medication link warrants Other Specified Sexual Dysfunction pending further evaluation.

Distinguish repetitive body-focused behavior caused by a medication's known effect from primary Obsessive-Compulsive and Related Disorder symptoms.

Recognize Pica's core pattern of eating nonfood substances, distinguished from ARFID's avoidance or restriction of actual food.

Recognize Premature (Early) Ejaculation's core timing complaint despite intact desire, distinguished from Male Hypoactive Sexual Desire Disorder.

Distinguish panic-like symptoms caused by a medication's pharmacological effect from Panic Disorder.

Recognize a sedative-hypnotic-anxiolytic-related disorder driven by escalating use of a prescribed medication, distinguished from alcohol use disorder by the specific substance class involved.

Recognize akathisia as a medication-induced movement disorder that can be mistaken for worsening psychiatric agitation, and distinguish it from catatonia.

Recognize Atypical Anorexia Nervosa's core teaching point: eating-disorder psychology and medical risk without low body weight.

Distinguish a NREM Sleep Arousal Disorder (sleep terror) from Nightmare Disorder using timing in the night, level of responsiveness, and dream recall.

Distinguish Developmental Coordination Disorder's isolated motor deficit from the broad, multi-domain deficits of Intellectual Disability.

Distinguish Somatic Symptom Disorder's real-symptom-plus-excessive-response pattern from Illness Anxiety Disorder's symptom-independent worry.

Apply the 3-month duration criterion distinguishing Other Specified Sleep-Wake Disorder from Insomnia Disorder.

Distinguish Psychological Factors Affecting Other Medical Conditions, where a psychological factor measurably worsens a diagnosed disease, from Somatic Symptom Disorder's excessive preoccupation with symptoms.

Distinguish NCD Due to HIV Infection from Substance/Medication-Induced NCD when both HIV status and substance history are present.

Recognize Substance/Medication-Induced Major or Mild Neurocognitive Disorder's persistence beyond acute intoxication/withdrawal, distinguished from a co-occurring neurodegenerative cause.

Distinguish Neurocognitive Disorder Due to Traumatic Brain Injury's cognitive-decline core from PTSD's re-experiencing, avoidance, and hyperarousal symptoms following the same traumatic event.

Distinguish obsessive-compulsive symptoms caused directly by a medical/infectious trigger from a medication-induced presentation.

Distinguish Binge-Eating Disorder's binge-without-compensation pattern from Bulimia Nervosa, and clarify that body weight alone does not decide the differential.

Distinguish Conduct Disorder's genuine rights-violating pattern from Oppositional Defiant Disorder's defiance-without-rights-violation pattern.

Recognize Intermittent Explosive Disorder's pattern of impulsive, grossly disproportionate outbursts in an adult, distinguished from DMDD and ODD.

Recognize Tourette's Disorder's required combination of motor AND vocal tics with a premonitory urge, distinguished from Stereotypic Movement Disorder and OCD.

Distinguish Histrionic Personality Disorder's broad need for attention and emotional expressiveness from Narcissistic Personality Disorder's grandiosity and need for admiration tied to self-image.

Distinguish OCD's obsession-compulsion cycle from GAD's diffuse worry and from a delusional belief.

Distinguish Specific Phobia's discrete, non-social trigger from Social Anxiety Disorder's scrutiny-based fear and from Panic Disorder's fear of the panic attacks themselves.

Identify the distinctive presentation of Inhalant-Related Disorders, distinguished from Alcohol Use Disorder by substance class and characteristic physical findings.

Recognize Prolonged Grief Disorder's pattern of persistent, impairing yearning and preoccupation well beyond expected cultural norms, distinguished from Major Depressive Disorder's broader mood and cognitive symptoms.

Recognize Delirium's acute, fluctuating course and identifiable medical trigger, distinguished from Major Neurocognitive Disorder due to Alzheimer's Disease's gradual course and from a depressive presentation.

Distinguish a major depressive episode from normal adjustment stress and from a bipolar-spectrum presentation.

Recognize Male Hypoactive Sexual Desire Disorder's primary deficiency in sexual thoughts and desire, distinguished from Erectile Disorder, where desire is intact but erections are physically difficult to attain.

Recognize the catatonia specifier as a transdiagnostic psychomotor syndrome, distinguished from schizophrenia and from ordinary depressive psychomotor retardation.

Recognize Hoarding Disorder's pattern of persistent difficulty discarding and distress at the thought of it, distinguished from OCD's obsession-driven rituals.

Distinguish Social Anxiety Disorder's fear of scrutiny in specific social/performance situations from Specific Phobia's narrower single-trigger fear and from Avoidant Personality Disorder's pervasive, trait-level relational pattern.

Distinguish Social (Pragmatic) Communication Disorder's isolated pragmatic-language deficit from Autism Spectrum Disorder, which additionally requires restricted or repetitive behaviors.

Distinguish Major Neurocognitive Disorder due to Alzheimer's Disease's gradual, progressive decline from Delirium's acute, fluctuating course and from Vascular Neurocognitive Disorder's stepwise pattern.

Recognize Dissociative Identity Disorder's pattern of distinct identity states and recurrent amnesia, distinguished from Borderline Personality Disorder's identity disturbance and from PTSD's dissociative symptoms.

Recognize Dissociative Amnesia as a standalone memory disturbance, distinguished from Dissociative Identity Disorder's broader identity fragmentation.

Distinguish a Circadian Rhythm Sleep-Wake Disorder driven by a schedule mismatch from Insomnia Disorder, which persists regardless of sleep timing.

Recognize Enuresis as the urinary elimination disorder, distinguished from Encopresis by the substance involved and the typical underlying mechanism.

Distinguish Borderline Personality Disorder's reactive, long-standing relational and identity pattern from a discrete Bipolar II hypomanic episode and from PTSD organized around a specific trauma.

Distinguish early psychotic symptoms of schizophrenia from mood-episode-related psychotic features and from a substance-induced presentation.

Recognize Tobacco Use Disorder's craving, failed quit attempts, and continued use despite harm, distinguished from a milder caffeine-related presentation.

Recognize Specific Learning Disorder's circumscribed academic deficit against an otherwise typical profile, distinguished from Intellectual Disability's generalized pattern.

Recognize Opioid Use Disorder's pattern of impaired control, social impairment, risky use, and pharmacological criteria, distinguished from appropriate medical use and from Alcohol Use Disorder.

Distinguish a manic episode from ordinary stress-related energy and from a substance-induced presentation.

Recognize Stereotypic Movement Disorder's pattern of fixed, rhythmic, driven movement causing self-injury, distinguished from tic disorders.

Recognize Separation Anxiety Disorder's pattern of fear specifically anchored to attachment-figure separation, distinguished from broader, multi-domain worry.

Recognize Vascular Neurocognitive Disorder's stepwise course tied to vascular events, distinguished from Alzheimer's-type gradual decline and from Delirium's acute fluctuating course.

Recognize Agoraphobia's pattern of marked fear across multiple situation types due to escape difficulty, distinguished from Panic Disorder's focus on the panic attacks themselves.

Recognize Selective Mutism's situation-specific failure to speak despite speaking normally elsewhere, distinguished from the broader pattern of Social Anxiety Disorder.

Recognize Schizotypal Personality Disorder's combination of social discomfort, odd beliefs, and eccentricity, falling short of a full psychotic disorder.

Recognize Oppositional Defiant Disorder's pattern of angry, argumentative, and vindictive behavior toward authority figures, distinguished from Conduct Disorder's violation of others' basic rights and from ADHD-driven impulsivity.

Recognize Brief Psychotic Disorder's duration-bound, sudden-onset psychosis with full-recovery expectation, distinguished from Schizophreniform Disorder and Schizophrenia by duration alone.

Distinguish Panic Disorder from generalized worry and from a medical cause of similar physical symptoms.

Recognize Bipolar II Disorder's hypomanic episode pattern -- distinct in duration, severity, and impairment from Cyclothymic Disorder's chronic subthreshold mood swings and from Bipolar I Disorder's manic episodes.

Recognize Factitious Disorder's pattern of deliberately produced illness without an identifiable external incentive, distinguished from malingering.

Recognize Neurocognitive Disorder with Lewy Bodies' core symptom cluster, distinguished from Parkinson's disease NCD by the timing of motor versus cognitive symptom onset.

Distinguish the broader hallucinogen-related presentation (including persisting perceptual disturbance) from a formal Substance/Medication-Induced Psychotic Disorder, which requires predominant, clinically significant hallucinations or delusions.

Recognize Conversion Disorder's genuinely involuntary neurological-type symptoms established through positive exam findings, distinguished from Factitious Disorder and malingering.

Recognize when symptom count, not behavior severity, is the reason a presentation falls short of Oppositional Defiant Disorder.

Distinguish Paranoid Personality Disorder's pervasive distrust from Schizotypal Personality Disorder, which additionally requires odd beliefs, perceptual experiences, or eccentricity.

Recognize Nightmare Disorder as a standalone sleep disturbance, distinguished from PTSD's fuller trauma-related symptom picture.

Apply the 6-month duration criterion distinguishing Brief Somatic Symptom Disorder from full Somatic Symptom Disorder.

Recognize Neurocognitive Disorder Due to Multiple Etiologies when positive evidence supports more than one contributing cause, distinguished from attributing the full picture to vascular disease alone.

Recognize Acute Stress Disorder's duration-bound pattern following trauma exposure, distinguished from PTSD by timing and from Adjustment Disorder by the trauma-exposure threshold.

Recognize Dependent Personality Disorder's pervasive, longstanding pattern of needing to be cared for, distinguished from dependent features arising during a mood episode.

Recognize when persistent psychotic symptoms fall short of Schizophrenia's full symptom-breadth requirement.

Distinguish Schizoaffective Disorder -- where mood episodes and psychosis overlap but psychotic symptoms also occur independently -- from Schizophrenia and from Bipolar I Disorder with psychotic features.

Distinguish Erectile Disorder, where desire is intact but erections cannot be attained or maintained, from Male Hypoactive Sexual Desire Disorder, where desire itself is diminished.

Recognize Depersonalization/Derealization Disorder's persistent detachment with intact reality testing, distinguished from DID and from panic-attack-limited dissociation.

Recognize Encopresis and its common constipation-and-overflow mechanism, distinguished from Enuresis by the substance involved.

Recognize how DSM-5-TR's two developmentally distinct Gender Dysphoria criteria sets apply depending on pubertal stage, and that the diagnosis requires clinically significant distress or impairment, not gender incongruence alone.

Recognize Language Disorder's isolated deficit in language content and structure, distinguished from Autism Spectrum Disorder's broader social-communication and behavioral pattern.