Chapter 5
The ability of an assay to distinguish the targeted analyte from interfering substances within the specimen matrix is called: a. Analytical specificity b. Analytical sensitivity c. Clinical specificity d. Clinical sensitivity
a. Analytical specificity
When performing a receiver operating curve analysis, what parameter assesses the overall efficacy of an assay? a. Area under the curve b. Performance limit (threshold) c. Positive predictive value d. Negative predictive value
a. Area under the curve
What agency provides continuing medical laboratory education? a. Colorado Association for Continuing Medical Labora- tory Education (CACMLE) b. Clinical Laboratory Improvement Advisory Committee (CLIAC) c. Centers for Medicare and Medicaid Services (CMS) d. College of American Pathologists (CAP)
a. Colorado Association for Continuing Medical Labora- tory Education (CACMLE)
A WBC count control has a mean value of 6000/mL and a standard deviation of 300/mL. What is the 95.5% confidence interval? a. 3000 to 9000/mL b. 5400 to 6600/mL c. 5500 to 6500/mL d. 5700 to 6300/mL
b. 5400 to 6600/mL
Regular review of blood specimen collection quality is an example of: a. Postanalytical quality assurance b. Preanalytical quality assurance c. Analytical quality control d. External quality assurance
b. Preanalytical quality assurance
The acceptable hemoglobin control value range is 13 6 0.4 g/dL. The control is assayed five times and produces the following five results: 12.0 g/dL 12.3 g/dL 12.0 g/dL 12.2 g/dL 12.1 g/dL These results are: a. Accurate but not precise b. Precise but not accurate c. Both accurate and precise d. Neither accurate nor precise
b. Precise but not accurate
You require your laboratory staff to annually perform manual lupus anticoagulant profiles on a set of plasmas with known values. This exercise is known as: a. Assay validation b. Proficiency testing c. External quality assessment d. Pre-pre analytical variable assay
b. Proficiency testing
Which is a statistical test comparing means? a. Bland-Altman b. Student's t-test c. ANOVA d. Pearson
b. Student's t-test
You perform a clinical efficacy test and get the following results: *Picture* What is the number of false-negative results? a. 40 b. 10 c. 5 d. 45
c. 5
What agency provides external quality assurance (proficiency) surveys and laboratory accreditation? a. Clinical Laboratory Improvement Advisory Committee (CLIAC) b. Centers for Medicare and Medicaid Services (CMS) c. College of American Pathologists (CAP) d. Joint Commission
c. College of American Pathologists (CAP)
You validate a new assay using linear regression to compare assay calibrator results with the distributor's published calibrator results. The slope is 0.99 and the y intercept is 110%. What type of error is present? a. No error b. Random error c. Constant systematic error d. Proportional systematic error
c. Constant systematic error
You purchase a preserved whole blood specimen from a distributor who provides the mean values for several complete blood count analytes. What is this specimen called? a. Normal specimen b. Calibrator c. Control d. Blank
c. Control
Review of laboratory report integrity is an example of: a. Preanalytical quality assurance b. Analytical quality control c. Postanalytical quality assurance d. External quality assurance
c. Postanalytical quality assurance
What procedure is employed to validate a new assay? a. Comparison of assay results to a reference method b. Test for assay precision c. Test for assay linearity d. All of the above
d. All of the above
The laboratory purchases reagents from a manufacturer and develops an assay using standard references. What FDA category is this assay? a. Cleared b. Home-brew c. Research use only d. Analyte-specific reagent
d. Analyte-specific reagent
A laboratory scientist measures prothrombin time for plasma aliquots from 15 healthy males and 15 healthy females. She computes the mean and 95.5% confidence interval and notes that they duplicate the manufacturer's statistics within 5%. This procedure is known as: a. Confirming linearity b. Setting the reference interval c. Determining the therapeutic ranged. d. Establishing the reference interval by transference
d. Establishing the reference interval by transference