SOLUTIONS GRADED A++
Which of the following statements best describes a quality assurance program of
clinical laboratories?
Check every aspect of the entire testing process including pre-analytical, analytical and
post-analytical phases
Which of the following is an example of preanalytical error?
A specimen that is mislabeled
Which of the following is NOT a part of the quality assurance program of a clinical
laboratory?
Refer patients to specialists based on appropriate test results
Which of the following best describes quality control in clinical laboratories?
It ensures a particular test method is working properly.
A patient had a new screening test for HIV. The test indicated that the patient is
not infected. But actually he is infected. Which of the following properly
describes the test result?
False negative
Relative Risk
a likelihood to have the incident in an exposed group compared to non-exposed group
Attributable Risk
It measures excess risk that is attributed to the exposure.
,Case-Control Study
Choose two groups (with or without incident) A researcher goes back their history to
check if they expose to the factor or not.
Odd Ratio
a measurement of association between an exposure and an outcome
Cohort Study
Choose a population and separate them into two groups (with or without exposure) A
researcher follow their life from now to check if they will have an incident or not.
A disease is treatable and has very poor prognosis if untreated. There is no
serious consequence associated with false positive result. Which of the following
test is desirable for diagnosis of such disease?
A test with high diagnostic sensitivity
How do we interpret relative risk?
Relative risk higher than 1 = positive association, causal
Which of the following statement is true about population and individual risks?
Not everyone exposed to the population risk factors develops the disease.
Accuracy
how close to the true value
Precision
random variation
Mean
average
Median
, value occurs in the middle of the population
For most analytes, normal reference range is set as a 95% confidence interval of
normal population. This is equal to:
± 2SD
Considering normal reference intervals utilized, X1 percent of the time, healthy
people will fall outside this range, and X2 percent of the time, healthy people will
fall within this range
X1 = 5, X2 =95
Which of the following individuals should be excluded when establishing a
normal reference range for blood pressure?
A 45-years old school teacher who had a heart attach last year
Which of the following can be used to partition groups into subclasses when
establishing a normal reference range for Hb?
Age
Which of following is NOT helpful to decided if a normal reference range needs to
be partitioned for subclass?
size of the subclass population
If you set the cut off between normal and abnormal (disease) as see in the figure,
what will happen to diagnostic specificity and diagnostic sensitivity? (cutoff
moved to the right)
increase diagnostic specificity, decrease diagnostic sensitivity