Burtis, et al: Tietz Fundamentals of Clinical Chemistry, 6th Edition
Test Bank
Chapter 1: Principles of Clinical Chemistry and Evidence-Based
Laboratory Medicine
MULTIPLE CHOICE
1. During diagnostic accuracy studies in evidence-based laboratory medicine, a laboratory test
being studied, for example, produces results that are compared with the “gold standard” of
testing, which would be the currently used assay or assay system. The test of interest is
referred to as
A. index test.
B. reference standard.
C. outcome study.
D. practice test.
ANS: A
An index test is the method being assessed, and the results of the index test are compared
with the reference standard, which is the current best practice, or method, used to obtain
results.
DIF: 1 REF: Pages 1, 4 OBJ: 5
2. In reading a research article, you determine that the study design was flawed because there
was no control group. This is an example of a weakness in
A. internal reliability.
B. internal validity.
, C. external reliability.
D. external validity.
ANS: B
Problems in the design of a study are considered to be poor internal validity and will
produce systematic error because the estimates of diagnostic accuracy differ from those one
would have obtained using an optimal design for the study.
DIF: 2 REF: Pages 1, 4 OBJ: 6
3. When developing clinical practice guidelines, what is the critical first step?
A. Requesting input from health insurance companies and government officials
B. Preparing a cost analysis based on patient needs
C. Determining the intended group that will be directly involved with implementation
D. Selecting and refining the topic upon which the investigation will center
ANS: D
Selection and refinement of the topic needing investigation must be accomplished before
target groups are chosen and primary evidence is assessed. Scope, topic, and clinical area
must all be addressed within the abilities of the group initiating guideline development.
DIF: 2 REF: Page 13 OBJ: 13
4. Another way that “bias” can be defined is as _____ error.
A. random
B. systematic
C. analytical
D. clinical
, ANS: B
Bias is systematic error that occurs when there is constant overestimation or
underestimation of a measured value.
DIF: 1 REF: Pages 1, 4 OBJ: 5
5. Internal validity is
A. the degree to which the variables in the study apply to all individuals in the study.
B. the degree to which the results of your sample can be inferred to the general
population outside of your study.
C. equal to consistency.
D. is the calculation of mean and variance from repeated measures.
ANS: A
Internal validity is the degree to which the results of a study can be trusted for the
population of patients in the study.
DIF: 1 REF: Pages 1, 4 OBJ: 6
6. A new hormone analyzer is received in the lab. By assaying a control sample 50 times and
assessing the mean and variance of the results, you are checking the _____of the instrument.
A. sensitivity
B. accuracy
C. validity
D. reliability
ANS: D
Reliability is related to consistency, whereas accuracy and sensitivity are related to validity.
Checking a sample 50 times determines how consistent the analyzer is when producing
results for the same sample.
, DIF: 2 REF: Page 2 OBJ: 5|6
7. A research study was prepared to assess the diagnostic accuracy of a therapeutic drug
monitoring assay for HMG-CoA reductase inhibitors (statins). The study was flawed with
poor design. Which of the following statements are correct?
A. Random error decreased
B. Systematic error decreased
C. Systematic error increased
D. A and B are both correct.
ANS: C
Poor internal validity caused by poor study design produces systematic error.
DIF: 2 REF: Page 4 OBJ: 5|6
8. Determine if the following study design is a randomized control trial or a case-control
study: Analysis of leptin in breast milk of obese versus nonobese breast-feeding mothers.
A. Randomized control trial
B. Case-control study
ANS: B
Randomized control studies typically examine a single randomly selected sample, who are
then further randomly assigned to either the treatment group (index) or the control group
(reference). Case-control studies examine two groups, one of which already has the disease
in question (cases) and one that does not (controls).
DIF: 3 REF: Pages 9, 15 OBJ: 9
Test Bank
Chapter 1: Principles of Clinical Chemistry and Evidence-Based
Laboratory Medicine
MULTIPLE CHOICE
1. During diagnostic accuracy studies in evidence-based laboratory medicine, a laboratory test
being studied, for example, produces results that are compared with the “gold standard” of
testing, which would be the currently used assay or assay system. The test of interest is
referred to as
A. index test.
B. reference standard.
C. outcome study.
D. practice test.
ANS: A
An index test is the method being assessed, and the results of the index test are compared
with the reference standard, which is the current best practice, or method, used to obtain
results.
DIF: 1 REF: Pages 1, 4 OBJ: 5
2. In reading a research article, you determine that the study design was flawed because there
was no control group. This is an example of a weakness in
A. internal reliability.
B. internal validity.
, C. external reliability.
D. external validity.
ANS: B
Problems in the design of a study are considered to be poor internal validity and will
produce systematic error because the estimates of diagnostic accuracy differ from those one
would have obtained using an optimal design for the study.
DIF: 2 REF: Pages 1, 4 OBJ: 6
3. When developing clinical practice guidelines, what is the critical first step?
A. Requesting input from health insurance companies and government officials
B. Preparing a cost analysis based on patient needs
C. Determining the intended group that will be directly involved with implementation
D. Selecting and refining the topic upon which the investigation will center
ANS: D
Selection and refinement of the topic needing investigation must be accomplished before
target groups are chosen and primary evidence is assessed. Scope, topic, and clinical area
must all be addressed within the abilities of the group initiating guideline development.
DIF: 2 REF: Page 13 OBJ: 13
4. Another way that “bias” can be defined is as _____ error.
A. random
B. systematic
C. analytical
D. clinical
, ANS: B
Bias is systematic error that occurs when there is constant overestimation or
underestimation of a measured value.
DIF: 1 REF: Pages 1, 4 OBJ: 5
5. Internal validity is
A. the degree to which the variables in the study apply to all individuals in the study.
B. the degree to which the results of your sample can be inferred to the general
population outside of your study.
C. equal to consistency.
D. is the calculation of mean and variance from repeated measures.
ANS: A
Internal validity is the degree to which the results of a study can be trusted for the
population of patients in the study.
DIF: 1 REF: Pages 1, 4 OBJ: 6
6. A new hormone analyzer is received in the lab. By assaying a control sample 50 times and
assessing the mean and variance of the results, you are checking the _____of the instrument.
A. sensitivity
B. accuracy
C. validity
D. reliability
ANS: D
Reliability is related to consistency, whereas accuracy and sensitivity are related to validity.
Checking a sample 50 times determines how consistent the analyzer is when producing
results for the same sample.
, DIF: 2 REF: Page 2 OBJ: 5|6
7. A research study was prepared to assess the diagnostic accuracy of a therapeutic drug
monitoring assay for HMG-CoA reductase inhibitors (statins). The study was flawed with
poor design. Which of the following statements are correct?
A. Random error decreased
B. Systematic error decreased
C. Systematic error increased
D. A and B are both correct.
ANS: C
Poor internal validity caused by poor study design produces systematic error.
DIF: 2 REF: Page 4 OBJ: 5|6
8. Determine if the following study design is a randomized control trial or a case-control
study: Analysis of leptin in breast milk of obese versus nonobese breast-feeding mothers.
A. Randomized control trial
B. Case-control study
ANS: B
Randomized control studies typically examine a single randomly selected sample, who are
then further randomly assigned to either the treatment group (index) or the control group
(reference). Case-control studies examine two groups, one of which already has the disease
in question (cases) and one that does not (controls).
DIF: 3 REF: Pages 9, 15 OBJ: 9
