The laboratory technologists are discussing a new blood test that ...

[nelaaney]

The laboratory technologists are discussing a new blood test that helps establish a differential diagnosis between shortness of breath with a cardiac etiology and shortness of breath with a respiratory/pulmonary etiology.
 
  A positive result is purported to indicate a cardiac etiology. The marketers of the test report that 99.8 of patients who have confirmed cardiac etiologies test positive in the test. However, 1.3 of patients who do not have cardiac etiologies for their shortness of breath also test positive. Which of the following statements best characterizes this blood test?
  A)
  Low validity; high reliability
  B)
  High sensitivity; low specificity
  C)
  High specificity; low reliability
  D)
  High sensitivity; low reliability

Question 2

The nurse is explaining the workings of selective serotonin reuptake inhibitors to a client with a diagnosis of depression. Within the teaching, the nurse mentions that in the nervous system, the transmission of information by neurotransmitters is
 
  A)
  synaptic signaling.
  B)
  endocrine signaling.
  C)
  autocrine signaling.
  D)
  paracrine signaling.

[yeungji]

Answer to Question 1

Ans:
B

Feedback:

A large number of patients would receive the correct positive diagnosis (high sensitivity), while a significant number would receive a false-positive diagnosis (low specificity). The information given does not indicate low reliability or low validity.

Answer to Question 2

Ans:
A

Feedback:

Synaptic signaling occurs in the nervous system, where neurotransmitters act only on adjacent nerve cells through special contact areas called synapses. Endocrine signaling relies on hormones carried in the bloodstream to cells throughout the body. Autocrine signaling occurs when a cell releases a chemical into the extracellular fluid that affects its own activity. With paracrine signaling, enzymes rapidly metabolize the chemical mediators and therefore act mainly on nearby cells.