USMLE USMLE Certifications USMLE-STEP-1 Questions & Answers

• Question 71:

  Taking a careful history of a 20-year-old female patient suffering from dissociative identity disorder is likely to reveal which of the following?

  A. a history of criminal behavior during childhood

  B. an excellent school record

  C. physical or sexual abuse in childhood

  D. setting of fires in childhood

  Correct Answer: C

  Section: Behavioral Science and Biostatics Dissociative identity disorder (multiple personality disorder) is often associated with a history of severe emotional, physical, or sexual abuse in childhood. The dissociation may serve an adaptive function that enables the patient to tolerate an intolerable situation. The patient's school record is often poor due to memory disturbance associated with the disorder. Choices A and D are associated with antisocial personality, and choice A is unlikely because dissociation often causes inattention and poor school grades.

• Question 72:

  A 72-year-old man is discovered wandering in the hot sun by hospital staff several hours after being reported missing. Recommended testing involves analysis of serum electrolytes. The assay revealed the following serum values: Na+ 150 mEq/L, K+ 5.2 mEq/L. Which of the following is the most likely diagnosis?

  A. Alzheimer's disease

  B. delirium

  C. lewy body dementia

  D. secondary dementia

  E. seizure disorder

  Correct Answer: B

  Section: Behavioral Science and Biostatics

  The hypernatremia and hyperkalemia are indicative of dehydration, which is a common cause of delirium.

  Choices A, C, D, and E do not explain this phenomenon.

• Question 73:

  Which of the following is the most characteristic element of managed care?

  A. Capitated payment.

  B. That it emphasizes prevention and health promotion.

  C. That it is a fee-for-service system.

  D. That it provides primary care.

  E. That physicians may be salaried.

  Correct Answer: A

  Section: Behavioral Science and Biostatics Managed care involves an entity (company, state, organization) managing health care through a capitated (head count) payment system. Within the managed care system, there are various models including specialized care and fee for service in addition to capitation.

• Question 74:

  Which of the following statements is true concerning infant mortality in the United States?

  A. Infant mortality in the United States is high compared to other developed nations.

  B. Prenatal care, disappointingly, has not been shown to reduce infant mortality.

  C. The leading cause of infant mortality in the United States is tetanus.

  D. The mortality rate for white infants is greater than that of black infants.

  E. Very few Asian Americans receive prenatal care as compared to African Americans or Hispanic Americans.

  Correct Answer: A

  Section: Behavioral Science and Biostatics The infant mortality rate in the United States is 8.9 deaths per 1000 live births as of 1989, which ranks the United States behind 11 other developed countries. The leading causes of infant death are congenital anomalies, respiratory distress syndrome, and sudden infant death syndrome; therefore, choice C is incorrect. Choices B, D, and E are incorrect because prenatal care does reduce infant mortality, but only 80% of Caucasian women receive prenatal care, followed by 75% of Asian American women, 65% of African American women, and 60% of Native American women. The infant mortality rate for black infants is greater than that of white infants.

• Question 75:

  Your patient reports that she is suffering from dizziness and persistent feelings that she is going to die. You inquire as to whether she has been using any illicit substances lately to which she indicates that she has not. She indicates that she has been curtailing going outside, especially in open spaces, because she is afraid that she might have one of those attacks and become immobilized, which of the following is the most likely diagnosis?

  A. acute anxiety attack

  B. agoraphobia with panic attack

  C. agoraphobia without panic attack

  D. anxiety secondary to a medical condition

  E. cocaine withdrawal

  Correct Answer: B

  Section: Behavioral Science and Biostatics The symptoms of panic associated with fear and avoidance of being in places where escape may be difficult or embarrassing call for the consideration of agoraphobia with panic attack. Choices A, C, D, and E are not associated with the phenomenon described here.

• Question 76:

  Which of the following implies the multiaxial diagnostic system in psychiatric disorders?

  A. All psychiatric disorders are personality disorders.

  B. Psychiatric disorders and other diseases can coexist.

  C. Psychiatric disorders are a subset of medical diseases.

  D. Psychiatric disorders are complex.

  Correct Answer: B

  Section: Behavioral Science and Biostatics Axis I of the multiaxial system is for clinical psychiatric disorders such as schizophrenia and mood disorders. Axis II is for personality disorders and mental retardation. Axis III is for general medical conditions (such as myocardial infarction). Axis IV is for psychosocial and environmental problems and Axis V is for global assessment of functioning. This classificatory system clearly indicates that psychiatric disorders (Axis I) and general medical disorders (Axis III) often do coexist and may influence each other. Choices A, C, and D are not part of the multiaxial system.

• Question 77:

  Your patient reports being frightened by heart palpitations and dizziness. Further evaluation reveals that the patient has used a substance heavily, but stopped about 3 days prior to experiencing symptoms, which of the following is the most likely substance used?

  A. alprazolam

  B. cannabis

  C. cocaine

  D. dextroamphetamine

  E. heroin

  Correct Answer: A

  Section: Behavioral Science and Biostatics Benzodiazepine withdrawal is often associated with anxiety symptoms. Cocaine (choice C) may cause a "crash" with anxiety soon after cessation of use, but by day 3 there is more likely to be dysphoria than anxiety. Although withdrawal from other substances (choices B, D, and E) can cause similar anxiety, benzodiazepine withdrawal is the most common cause of this type of symptomatology

• Question 78:

  Which of the following is an id function?

  A. aggression

  B. cognition

  C. conscience

  D. perception

  E. psychological defense mechanisms

  Correct Answer: A

  Section: Behavioral Science and Biostatics The id is the collection of psychological functions having to do with basic instincts, such as sex and survival. Aggression is a basic instinct, therefore, an id function. The ego functions to mediate between the personality system on one hand and the demands of external reality and the superego on the other hand. Thus, psychological defense mechanisms (choice E), perception (choice D), and cognition (choice B) are all ego functions. Superego is the part of the personality system that encompasses conscience (choice C).

• Question 79:

  A 72-year-old woman is brought to the clinic by her family because she is exhibiting confusion. Upon mental status examination, the patient demonstrates fluctuating levels of awareness. For example, she seems lucid 1 minute, then becomes somnolent or stuporous the next. Which of the following is most likely?

  A. delirium

  B. dementia

  C. factitious illness

  D. malingering

  E. stupor

  Correct Answer: A

  Section: Behavioral Science and Biostatics Fluctuating levels of awareness are characteristic of delirium, which is indicative of an encephalopathy due to metabolic derangement of the brain, such as anoxia, electrolyte imbalance, or hypoglycemia. Although delirium may be superimposed on dementia, at this point there is no evidence that the patient has the more stable cognitive deficits characteristic of dementia (choice B). Coma (choice D) and stupor (choice E) refer to more severe disturbance of sensorium. Factitious illness (choice C) is unlikely unless there is evidence of selfinduced metabolic derangement.

• Question 80:

  An elderly patient, known to suffer from dementia, was found walking aimlessly in the fields in hot weather for several hours before being brought to the clinic. Which of the following would be the most useful laboratory test?

  A. electrocardiogram

  B. electroencephalogram

  C. pneumoencephalogram

  D. serum electrolyte levels

  E. urinalysis

  Correct Answer: D

  Section: Behavioral Science and Biostatics An elderly woman exposed to hot sunlight for hours may be dehydrated, and testing serum electrolyte levels may confirm this suspicion. Although the other tests (choices A, B, C, and E) may be indicated at some point, they are not the most urgent tests in this case.