NR547 Differential Diagnosis in Psychiatric-Mental Health
Across the Lifespan Practicum Final Exam Question Bank
(Latest 2026/2027 Edition) – Questions, Answers & Detailed
Rationales
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SECTION 1: Foundations of Differential Diagnosis and Diagnostic Reasoning
──────────────────────────────
Question 1
A 42-year-old female presents to the psychiatric-mental health nurse practitioner
(PMHNP) with complaints of persistent sadness, fatigue, and difficulty concentrating for
the past 6 weeks. She denies suicidal ideation but reports decreased appetite and
insomnia. Her medical history is significant for hypothyroidism. Which initial diagnostic
step is most essential before formulating a psychiatric differential diagnosis?
A. Initiating a selective serotonin reuptake inhibitor (SSRI) for presumed major
depressive disorder
B. Ordering a thyroid-stimulating hormone (TSH) level to assess thyroid function
C. Administering the Patient Health Questionnaire-9 (PHQ-9) as the sole diagnostic
instrument
D. Referring the patient immediately to a psychiatrist for complex case management
Correct Answer:
B — Ordering a thyroid-stimulating hormone (TSH) level to assess thyroid function
Rationale:
Hypothyroidism is a well-established medical mimic of depression; evaluating TSH is
essential to rule out physiologic causes before attributing symptoms to a primary
psychiatric disorder. Distractor A represents premature pharmacologic intervention
,without completing the differential diagnostic process, which violates fundamental
diagnostic reasoning principles.
Question 2
A PMHNP is evaluating a 19-year-old college student who presents with acute onset of
paranoia, disorganized speech, and auditory hallucinations following a week of heavy
amphetamine use. The patient's mother reports no prior psychiatric history. Which
principle of differential diagnosis best guides the initial diagnostic formulation?
A. Assuming schizophrenia spectrum disorder given the presence of first-rank
symptoms
B. Prioritizing substance-induced psychotic disorder in the differential given temporal
association with amphetamine use
C. Diagnosing brief psychotic disorder due to acute stress from academic pressures
D. Ruling out malingering before considering any genuine psychiatric condition
Correct Answer:
B — Prioritizing substance-induced psychotic disorder in the differential given temporal
association with amphetamine use
Rationale:
The temporal association between amphetamine use and psychotic symptoms strongly
suggests substance-induced psychotic disorder; DSM-5-TR requires ruling out
substances before diagnosing primary psychotic disorders. Distractor A incorrectly
prioritizes a primary psychotic disorder without considering the substance etiology,
which is a common diagnostic error.
Question 3
A 35-year-old male veteran presents with irritability, hypervigilance, intrusive memories
of combat, and emotional numbing. He also reports drinking 6-8 beers nightly to "quiet
,his mind." Which diagnostic approach best addresses the complexity of co-occurring
conditions?
A. Diagnosing post-traumatic stress disorder (PTSD) and deferring alcohol use
assessment until PTSD is stabilized
B. Diagnosing both PTSD and alcohol use disorder concurrently, recognizing their
bidirectional relationship
C. Attributing all symptoms to alcohol use disorder and deferring PTSD evaluation
D. Diagnosing adjustment disorder with mixed anxiety and depressed mood as the
primary condition
Correct Answer:
B — Diagnosing both PTSD and alcohol use disorder concurrently, recognizing their
bidirectional relationship
Rationale:
PTSD and alcohol use disorder frequently co-occur with bidirectional maintenance;
DSM-5-TR permits concurrent diagnoses, and integrated treatment addressing both
conditions yields superior outcomes. Distractor A represents sequential rather than
integrated diagnostic reasoning, which may delay necessary substance use
intervention.
Question 4
A PMHNP evaluates a 28-year-old woman with a 2-year history of fluctuating mood
symptoms, impulsivity, unstable relationships, and recurrent self-harm. The patient
reports that antidepressants prescribed by her primary care provider worsened her
mood swings. Which diagnostic consideration is most critical in this case?
A. Confirming bipolar II disorder based on antidepressant-induced mood elevation
B. Evaluating for borderline personality disorder as a primary or comorbid diagnosis
C. Diagnosing major depressive disorder with anxious distress and continuing
antidepressant therapy
D. Attributing symptoms to premenstrual dysphoric disorder given the patient's gender
, Correct Answer:
B — Evaluating for borderline personality disorder as a primary or comorbid diagnosis
Rationale:
The pattern of chronic interpersonal instability, impulsivity, self-harm, and affective
dysregulation in a young adult woman warrants evaluation for borderline personality
disorder; antidepressant intolerance may reflect emotional reactivity rather than
bipolarity. Distractor A risks misdiagnosing bipolar disorder based on antidepressant
effects without clear manic/hypomanic episodes.
Question 5
A 7-year-old boy is referred for evaluation due to declining academic performance,
difficulty following multi-step instructions, and frequent interrupting in class. His teacher
reports he is "always moving" and cannot wait his turn. Which diagnostic framework
best guides the PMHNP's assessment?
A. Applying adult ADHD criteria directly without developmental adjustment
B. Utilizing DSM-5-TR criteria for ADHD with multi-informant assessment across home
and school settings
C. Diagnosing oppositional defiant disorder based on classroom behavioral disruptions
D. Attributing symptoms to normal childhood energy and recommending behavioral
modification only
Correct Answer:
B — Utilizing DSM-5-TR criteria for ADHD with multi-informant assessment across home
and school settings
Rationale:
ADHD diagnosis in children requires symptom presence in multiple settings (home,
school) with multi-informant input (parents, teachers) and developmental
appropriateness of criteria. Distractor A violates developmental diagnostic principles,
while C misattributes core attentional symptoms to oppositionality.
Across the Lifespan Practicum Final Exam Question Bank
(Latest 2026/2027 Edition) – Questions, Answers & Detailed
Rationales
──────────────────────────────
SECTION 1: Foundations of Differential Diagnosis and Diagnostic Reasoning
──────────────────────────────
Question 1
A 42-year-old female presents to the psychiatric-mental health nurse practitioner
(PMHNP) with complaints of persistent sadness, fatigue, and difficulty concentrating for
the past 6 weeks. She denies suicidal ideation but reports decreased appetite and
insomnia. Her medical history is significant for hypothyroidism. Which initial diagnostic
step is most essential before formulating a psychiatric differential diagnosis?
A. Initiating a selective serotonin reuptake inhibitor (SSRI) for presumed major
depressive disorder
B. Ordering a thyroid-stimulating hormone (TSH) level to assess thyroid function
C. Administering the Patient Health Questionnaire-9 (PHQ-9) as the sole diagnostic
instrument
D. Referring the patient immediately to a psychiatrist for complex case management
Correct Answer:
B — Ordering a thyroid-stimulating hormone (TSH) level to assess thyroid function
Rationale:
Hypothyroidism is a well-established medical mimic of depression; evaluating TSH is
essential to rule out physiologic causes before attributing symptoms to a primary
psychiatric disorder. Distractor A represents premature pharmacologic intervention
,without completing the differential diagnostic process, which violates fundamental
diagnostic reasoning principles.
Question 2
A PMHNP is evaluating a 19-year-old college student who presents with acute onset of
paranoia, disorganized speech, and auditory hallucinations following a week of heavy
amphetamine use. The patient's mother reports no prior psychiatric history. Which
principle of differential diagnosis best guides the initial diagnostic formulation?
A. Assuming schizophrenia spectrum disorder given the presence of first-rank
symptoms
B. Prioritizing substance-induced psychotic disorder in the differential given temporal
association with amphetamine use
C. Diagnosing brief psychotic disorder due to acute stress from academic pressures
D. Ruling out malingering before considering any genuine psychiatric condition
Correct Answer:
B — Prioritizing substance-induced psychotic disorder in the differential given temporal
association with amphetamine use
Rationale:
The temporal association between amphetamine use and psychotic symptoms strongly
suggests substance-induced psychotic disorder; DSM-5-TR requires ruling out
substances before diagnosing primary psychotic disorders. Distractor A incorrectly
prioritizes a primary psychotic disorder without considering the substance etiology,
which is a common diagnostic error.
Question 3
A 35-year-old male veteran presents with irritability, hypervigilance, intrusive memories
of combat, and emotional numbing. He also reports drinking 6-8 beers nightly to "quiet
,his mind." Which diagnostic approach best addresses the complexity of co-occurring
conditions?
A. Diagnosing post-traumatic stress disorder (PTSD) and deferring alcohol use
assessment until PTSD is stabilized
B. Diagnosing both PTSD and alcohol use disorder concurrently, recognizing their
bidirectional relationship
C. Attributing all symptoms to alcohol use disorder and deferring PTSD evaluation
D. Diagnosing adjustment disorder with mixed anxiety and depressed mood as the
primary condition
Correct Answer:
B — Diagnosing both PTSD and alcohol use disorder concurrently, recognizing their
bidirectional relationship
Rationale:
PTSD and alcohol use disorder frequently co-occur with bidirectional maintenance;
DSM-5-TR permits concurrent diagnoses, and integrated treatment addressing both
conditions yields superior outcomes. Distractor A represents sequential rather than
integrated diagnostic reasoning, which may delay necessary substance use
intervention.
Question 4
A PMHNP evaluates a 28-year-old woman with a 2-year history of fluctuating mood
symptoms, impulsivity, unstable relationships, and recurrent self-harm. The patient
reports that antidepressants prescribed by her primary care provider worsened her
mood swings. Which diagnostic consideration is most critical in this case?
A. Confirming bipolar II disorder based on antidepressant-induced mood elevation
B. Evaluating for borderline personality disorder as a primary or comorbid diagnosis
C. Diagnosing major depressive disorder with anxious distress and continuing
antidepressant therapy
D. Attributing symptoms to premenstrual dysphoric disorder given the patient's gender
, Correct Answer:
B — Evaluating for borderline personality disorder as a primary or comorbid diagnosis
Rationale:
The pattern of chronic interpersonal instability, impulsivity, self-harm, and affective
dysregulation in a young adult woman warrants evaluation for borderline personality
disorder; antidepressant intolerance may reflect emotional reactivity rather than
bipolarity. Distractor A risks misdiagnosing bipolar disorder based on antidepressant
effects without clear manic/hypomanic episodes.
Question 5
A 7-year-old boy is referred for evaluation due to declining academic performance,
difficulty following multi-step instructions, and frequent interrupting in class. His teacher
reports he is "always moving" and cannot wait his turn. Which diagnostic framework
best guides the PMHNP's assessment?
A. Applying adult ADHD criteria directly without developmental adjustment
B. Utilizing DSM-5-TR criteria for ADHD with multi-informant assessment across home
and school settings
C. Diagnosing oppositional defiant disorder based on classroom behavioral disruptions
D. Attributing symptoms to normal childhood energy and recommending behavioral
modification only
Correct Answer:
B — Utilizing DSM-5-TR criteria for ADHD with multi-informant assessment across home
and school settings
Rationale:
ADHD diagnosis in children requires symptom presence in multiple settings (home,
school) with multi-informant input (parents, teachers) and developmental
appropriateness of criteria. Distractor A violates developmental diagnostic principles,
while C misattributes core attentional symptoms to oppositionality.
