BLD 313 Final Exam Quizzes
Which of the following is the best description of critical value? a) The concentration of an analyte above which is associated with acute negative patient outcomes b) Specimens which contain concentrations of interference sufficient to make analytes impossible c) Concentrations of analytes greater than the upper limit of linearity d) Concentrations of analytes which are above the reportable rlange
A
Which of the following is the mathematical expression of the relationship between absorbance and transmittance? a) A = 2- log %T b) A = log %T c) A = abc d) Au/Cu = As/Cs
A
Which of the following needs to be measured in order to determine specific gravity? a density b gravity c osmolality d osmolarity
A
Which of the following sets up standards for laboratory personnel, quality control and quality assurance based on test complexity and potential harm to the patient? a) CLIA'88 b) CDC c) FDA d) CMS
A
Which of the following statement is NOT true about medically allowable error? a It is established by CLIA. b) It is based on intra individual variation. c) It is based on difference between normal and disease distribution. d) It is based on normal reference range.
A
Which of the following statement is true about osmolality? a it is more accurate at measuring solution concentration b it is defined by osmols of solute particles c it is affected by temperature d it is calculated as a ratio between the densities of the substance and pure water
A
Which of the following statement is true about quality control? a) It is the personal who performs the test evaluates testing quality himself and documents the process for inspection. b) Quality control should be done at least twice a day for most tests. c) Only two controls abnormal high and low are required for most quality control process. d) No quality control is neededed if reagent is the only thing changes for the test.
A
You have 100 ml of a 0.50 M solution of NaCl. To this, you add 500 mg of dry NaCl. You now add water to the final volume of 1.0 liter. What is the molarity of this final solution? MW: Na=23.0, Cl- =35.5. a) 0.059M b) 5.9M c) 0.0059M d) 0.59M
A
Which one of the following points on a ROC curve represents the cutoff value that provides the greatest diagnostic accuracy? a) The point closest to the lower right-hand cornor of the plot b) The point closest to the upper left-hand cornor of the plot c) The point closest to the upper right-hand cornor of the plot d) The point closest to the lower left-hand cornor of the plot
B
Which of the following is an example of pre-analytic error? a) It covers all policies and procedures of a clinical laboratory. b) It is the same as quality assurance. c) It ensures the test results are reported properly to other health professionals. d) It ensures a particular test method is working properly.
C
Which of the following is the difference of incidence rates between the exposed and the unexposed group? a) Relative risk b) Odds ratio c) Attributable risk d) Absolute risk
C
Which of the following measures the signal change in magnitude? a) Duration b) Frequency c) Amplitude d) Rate
C
Which of the following over-estimates the concentration? a) Low noise b) Downward drift c) Upward drift d) High noise
C
Which of the following statement is NOT true about analytic range? a) It is defined by standard curve. b) Lower limit of detection indicates analytic sensitivity c) Analytic sensitivity is defined by the last data point on the standard curve d) It is also known as working range.
C
Which of the following statement is true about population and individual risks? a) Both population and individual risks can be measured. b) An individual within the population may not be susceptible to the effcts of the population risk factors c) Not everyone exposed to the population risk factors develops the disease. d) Individual risks but not population risks can be identified
C
Which of the following is a role of the clinical laboratory in managing a patient who has been diagnosed with AIDS? a) Contact the people who have sexual contact with the patient b) Initiate antiviral treatment c) Obtain previous medical history of the patient d) Determine the virus load
D
Which of the following is responsible for the evaluation and overview of laboratory developed tests in clinical laboratories? a) OSHA b) ASCP c) FDA d) CLIA
D
Which of the following signals is light based? a) Current b) Vapor pessure c) Voltage d) Absorbance
D
Which of the following statements about method evaluation is correct? a) It is an essential part of QC process. b It is an essential part of PT process. c) It determines medical allowable error. d) It is an essential part of QA process.
D
Which of the following statements about surveillance protocols for LDTs is true? a) It is need only put in place if requested by the institutional risk assessment committee. b) It is only required for LDTs which are classified as waived. c) It is optional once the LDT has approved. d) Its primary purpose is to document and address negative patient outcomes
D
Which of the following terms is equivalent to imprecision? a) Inaccuracy b) Total error c) Systemic error d) Random error
D
Your laboratory received the following PT scores on the same testing in three months: 2017/1, 100%; 2017/2, 50%; 2017/3, 70%. As a laboratory manager, what should you do? a) Shut down the laboratory b) Continue the testing while doing the investigation on failed PT c) Continue the testing till receiving the discontinuation notice from the accrediting agency d) Discontinue the testing
D
Which of the following is part of risk assessment of IQCP? a) Document quality control practices and procedures b) Identify source of errors c) Detect the errors d) Proficiency testing
B
Which of the following is pre-analytic variable which may influence the results of a test? a) The person who performs the test has never been trained properly b) Time when blood is drawn c) Calibration of the instrument d) Out of date quality control samples
B
A comparison of methods was done between the reference method and the method I seek to acquire LDT status for. This experiment produced a line of best fit with the corresponding formula Y = 0.95X + 0. What type of bias does my candidate for LDT status have? a) A 5% negative proportionality error b) A 5% positive constant error c) A 5% positive proportionality error d) No bias is present between the candidate and the reference method
A
A normal reference range of a screening test has increased. The sensitivity of the related screening test would change in which of the following ways? a) Decrease b) Can increase or decrease c) Increase d) Does not change
A
A patient was tested billirubin level of 2.0mg/dL. The next day the same test was done and his bilirubin level was 7.0mg/dL. Which of the following should be done? a) Perform delta check b) Repeat the second test c) Report the result as usual d) Call the physician immediately
A
A stock solution of HNO3 has a specific gravity of 1.42 and is 80% pure. How many milliliters of this stock are needed to make 200 ml of a 10.0% w/v solution HNO3? (MW: H=1.0, O=16.0, N=14.0) a) 17.5ml b) 141ml c) 14.1ml d) 175ml
A
If your medical requirements for glucose require that the total error be less than 6mg/dL at a concentration of 120mg/dL, and you know that your imprecision is 2mg/dL. What is the maximum bias that your method can have? a) 2.08mg/dL b) 1.96mg/dL c) 2.04mg/dL d) 2.00mg/dL
A
In 1 liter of solution that contains 0.05 moles of sodium acetate and 0.02 moles of acetic acid. What is the final pH of this solution? pK of acetic acid is 4.76. a) 5.2 b) 5.1 c) 5.4 d) 5.3
A
Increased risk is indicated by which of the following? a) Relative risk higher than 1 b) Absolute risk higher than 1 c) Attributable risk less than 1 d) Attributable risk higher than 1
A
Looking at a package insert for an assay kit, it indicates that concentration of triglycerides greater than 500 mg/dL causes significant interference. Of the following, which concerning this value is true? a) Results from specimens with concentrations of triglycerides greater than 500 mg/dL are erroneous b) The 500 mg/dL concentration is the maximum physiologic concentration of trilgyceride c) Specimens with concentrations of triglycerides greater than 500 mg/dL should be evaluated and results reported without note d) All of the above are false
A
Of the following subdivision of the FDA, in which are direct issues concerning clinical laboratory testing addressed? a) In vitro diagnosis b) Safety and health c) Labeling and labeling claims d Medical procedures
A
There are only five labs in this country offering the LDT I currently have under development and finding a commercial provider of proficiency testing is impossible. Which of the following proficiency protocols would best satisfy CLIA regulations concerning participation in a proficiency testing program? a) Establish a network with al the other labs where split specimens are shared three times per year and results are then compared b) Run all specimens in duplicate as they are received c) Once a year, send one of my specimens to another lab offering this test d) Repeat analysis on all specimens on the next day after their iniital measurement
A
To 9ml of water, 1 ml of serum is added. What is the dilution factor? a 10 b 9 c 11 d 8
A
To identify all patients infected by a virus, the cut-off point for this test should be set at the point of highest _______. a) Sensitivity b) Accuracy c) Reliability d) Specificity
A
To test for subclass difference between the calcium reference values for men and women, the means and standard deviations of each group are used to calculate a z value of 6.0. While the z critical value is 3.0. What conclusion can be drawn from such data? a) Separate reference intervals for men and women should be considered. b) The difference of calcium reference values between men and women is not statistically significant. c) The difference of calcium reference values between men and women is not clinically significant. d) The use of separate reference intervals for men and women is not justified here.
A
What is the molarity of a 5.0% m/v solution of MgCl2 5H2O? (MW: Cl-=35.5, H=1.0, Mg=24.3, H2O=18.0, N=14.0) a)270mM b) 525mM c) 27mM d 53mM
A
What is the pH of a 0.05 M solution of NaOH? a) 12.7 b) 12.5 c) 12.9 d) 12.3
A
What is the purpose of the reagent blank in spectrophotometric analysis? a) Correct for color contribution of the reagent b) Correct for interfering chromogens c) Correct for lipemia d) Correct for protein interference
A
Which of the following is an example of random error? a. An error caused by variations in reagents b) An error that is consistently high by the same amount regardless of the analyte concentration c) An error that is consistently high by an amount proportional to the analyte concentration d) An error that is consistently low by the same amount regardless of the analyte concentration
A
Which of the following is responsible for inspection and certification of the clinical laboratories? a) CMS b) CLIA'88 c) CDC d) FDA
A
Which of the following is used to determine a cut-off that will discriminate diseased from non-diseased when there is a significant overlap between the two populations? a) Linear regression analysis b) Receiver operated characteristic curve c) F-test d) ANOVA
B
Which of the following isolates light within a narrow region of the spectrum? a) Photomultiplier tube b) Monochromator c) Detector d) Photovoltaic cell
B
Which of the following should NOT be included in PT plan? a) Address the timely submission of PT results to align the time frame of accreditation b) Share PT results with the laboratories of the peer group c) Describe the procedures that ensure the PT samples are treated the same way as the patient specimen d) Determine the testing cycle of PT based on the accreditation requirement and cost
B
Which of the following statement is NOT true about medically allowable error? a) It is based on normal reference range. b) It is established by CLIA. c) It is based on difference between normal and disease distribution. d) It is based on intra individual variation
B
Which of the following individuals should be excluded when establishing a normal reference range for blood pressure? a) A 32-year-old woman b) A 40-year-old professional athlete who plays gymnastics c) A person who has smoked for two years d) A 18-year-old taxi driver
C
Which of the following best describes the reportable range of an assay? a) That range of concentration which can be entered into computerized data delivery systems b) The range of concentration bound by the upper limit of linearity and the lower limit of detection c) The range of concentration which can be directly reported out without modification, like dilution or concentration d) Is defined by the limit of dilution a very high concentration specimen can undergo and will still produces a reportable result
B
Which of the following can be used to interpret internal quality control data? a) Chi-square test b) Levey-Jennings c) Z test d) Linear regression
B
Which of the following can be used to partition groups into subclasses when establishing a normal reference range for Hb? a) Occupation b) Age c) Recreational drug use d) Disease
B
Which of the following is NOT a part of the quality assurance program of a clinical laboratory? A A safety program for both staff and patients b) Refer patients to specialists based on appropriate test results c) Quality control d) Staff performance evaluation
B
Which of the following is NOT part of a typical investigational device exemption (IDE) for a product undergoing the FDA approval process? a) Legal rights to the product b) Analytical performance c) A review of potential ethical issues the manufacturing or use of the product may encounter d) Qualification of manufacturer's personnel involved in the project
B
Which of the following is an example of semi-quantitative test result? a) Clear b) 3+ c) Presence d) 5.0 mg/dL
B
Which of the following is most often designated as the target value for most analytes in quantitative PT? a 3sd b peer group mean c medical allowable error d consensus
B
Which of the following is part of pre market approval (PMA) for a product undergoing the FDA approval process? a) Qualification of manufacturer's personnel involved in the project b) Clinical trials c) Legal rights to the product d) Completion of IRB
B
5.0 ml of a 1.0% w/v solution of NaCl is added to 10 ml of a 2.0% w/v solution of MgCl2. MgCl2 dissociates 100%. What is the final osmolality of this mixture? (MW: Na=23.0, Cl-=35.5, H=1.0, Mg=24.3, H2O=18.0, N=14.0) a) 0.50 b) 0.53 c) 0.47 d) 0.44
B
A 2.0M solution of NaCl is diluted 1/5. What is the final concentration? a 0.5 mol/L b 0.4 mol/L c 0.5 mmol/L d 0.4 mmol/L
B
A POCT coordinator distributed 1000 newly FDA approved glucometers. The users reported getting shocked when operating them. What should the coordinator do? a) Take the two meters back and ask for replacement from the manufacturer who will replace them but do nothing else. b) Return the two meters to the manufacturer who replaces them and reports to FDA of the defective devices c) Take the two meters back and send them to biomedical engineering department for repair. d) Take the two meters back that shock the users and throw them away and replace them with new meters.
B
A class of 400 college students who have normal blood glucose level and BMI were enrolled in a cohort study to investigate the association between body weight and development of diabetes. The students were followed for the next 40 years. By the time the data were collected, 300 of those students had the BMI of 25 or higher (overweight or obese) and the rest of 100 had the BMI less than 25. Of the 300 with higher than normal BMI, 210 of them had developed diabetes; of the 100 with normal BMI, 5 of them had developed diabetes. For a person with a BMI higher than 25, his risk of developing diabetes is how many times that of a person with normal BMI? a) 70 b) 14 c) 65 d) 5
B
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) A test of high specificity b) A test of high sensitivity c) A test with low positive predictive value d) A test with high negative predictive value
B
A stock solution of HNO3 has a specific gravity of 1.575 and is 80% pure. How many milliliters of this stock are needed to make 200 ml of a 10.0 N solution HNO3? (MW: H=1.0, O=16.0, N=14.0) a) 1000ml b) 100ml c) 800ml d) 80ml
B
Adding a variable amount of diluent to fixed amount of stock in each tube is a way of making which type of dilution? a serial b independent c fixed d simple
B
Consensus error can be calculated by which of the following? a) Accuracy and precision b) Mean and SD c) Allowable and bias error d) Bias and random error
B
For most analytes, the upper and lower reference limits are estimated to enclose what percentage of the values for a population from which reference subjects have been drawn? a) 2.5% b) 95% c) 5% d) 97.5%
B
If the new screening test has a sensitivity of 90% and a specificity of 70%. What is the positive predictive value of this test? a) 30% b) 75% c) 25% d) 88%
B
The concentration of a solution is 10M. It has an absorbance of 0.200 when placed in a 1.0cm cuvette at the wavelength of 250nm. What would be the absorbance if the solution is 5M? a) 0.050 b) 0.100 c) 0.150 d) 0.200
B
The distribution of values for a test from a normal population has been determined to be parametric. Determination of normal reference range would be best conducted by what method? a) Plus and minus a one standard deviation interval about the mean b) Plus and minus a two standard deviation interval about the mean c) Chi square distgribution d) Ordered data array in ascending order
B
The incidence rate is equivalent to which measure of the risk? a) Odds ratio b) Absolute risk c) Attributable risk d) Relative risk
B
The pK of acetic acid is 4.76. What is the pH of a 0.05 M solution of acetic acid? a) 1.0 b) 3.0 c) 2.0 d) 4.0
B
To 10 ml of a 0.10 M solution of HCl is added 5.0 ml of a 0.02 M solution of NaOH. What is the final pH of this mixture? a) 1.24 b) 1.22 c) 1.21 d 1.23
B
What is the normality of 1.0% w/v solution of NaOH (mw = 40.0)? a) 0.025N b) 0.25N c) 0.5N d)1.0N
B
Which of the following acts as a scientific authority and educational resource in administering CLIA'88 by conducting research and analysis and providing technical expertise? a) CLIA'88 b) CDC c) FDA d) CMS
B
Which of the following best describes the method for documentation of precision needed for CLIA approval of a LTD? a) Repeated measurement of a single specimen done after repeated recalibrations and reagent changes on the same day b) Repeated measurement of a single specimen done all in a single run at the same time c) Repeated measurement of a single specimen at the medical decision concentration one over several days, during different shift and different staff d) Determination a percent recovery from a pooled specimen acquired from your patieint population
B
Which of the following is NOT a part of literature review when seeking approval for a LDT? a) Evidence that this test has been scrutinized by the scientific sommunity b) Information on how implementation of the test will impact patient care c) Reportable range d) Description of the patient population that the test will serve
C
A blood sample is divided into two aliquots. One aliquat is analyzed directly; another one is analyzed after being physically traumatized. Which of the following does this experiment try to estimate? a) Proportional error b) Random error c) Constant error d) Total error
C
A chromophore has a molecular weight of 150. When 20 mg of this substance is placed in 500 ml of water, it produced an absorbance of 0.250. What is the molar absorptivity of this compound? (The cuvette path width is 1 cm). a) 93.75L/M∙cm b) 93.75L∙M/cm c) 937.5L/M∙cm d) 937.5L∙M/cm
C
A compound has a molar absorptivity of 1.50 x 10-2 l/m cm. if 1.00 ml of a solution containing this compound is placed in 5 ml of water, this final solution produced and absorbance of 1.500. What is the concentration of this compound in the original solution? a) 0.01M b) 0.02M c) 0.06M d) 0.05M
C
For 20 replicate measurements of a sample, the mean is 100.0mg/dL, a standard deviation is 1.0mg/dL. What is the random error? a) 2.0mg/dL b) 3.0mg/dL c) 4.0mg/dL d) 1.0mg/dL
C
How much 1.00 M stock solution of NaCl would you need to prepare 500 mL of a 1.00% w/v solution? (MW: Na=23.0, Cl=35.5) a 8.5 ml b 8.6 ml c 86 ml d 85 ml
C
IQCP applies to which of the following tests? a) Waived tests b) Tests that accuracy can be easily achieved c) All non-waived tests except for anatomic pathology and cytopathology d) Tests that have default QC of CLIA'88
C
The 95% confidence limit for calcium in control sera is reported as 8.0-10.0mg/dL. What is the value of the coefficient of variation (CV) for this data? a) 9% b) 10% c) 11% d) 12%
C
The peer group results of a PT event are 1.6, 1.4, 1.3, 1.2, 1.0, 1.3, 1.2, 1.2, 3.6, 1.1, and 0.8mg/dL. The acceptance limits are target value ± 0.3mg/dL or ± 20%, whichever is greater. How many laboratories among this peer group have failed this PT event? a 1 b2 c 3 d 0
C
Two 0.9 ml aliquots of the same specimen are placed in test tubes. To one is added 0.1 ml of water (Specimen A). To the other is added 0.1 ml of 200 mg/dl urea (Specimen B). Both specimens are analyzed for their urea content with the following results. Specimen A = 25 mg/dl Specimen B = 43 mg/dl What is the percent recovery of this method? a) 93% b) 99% c) 90% d) 96%
C
What is the molar absorptivity of a compound which produces an absorbance (A) of 0.250 at a concentration of 0.2 moles/liter in a cuvette path width of 2 cm? a) 0.625L∙M/cm b) 0.0625L/M∙cm c) 0.625L/M∙cm d) 0.0625L∙M/cm
C
What is the normality of a 1.0% w/v solution of H2SO4 (mv = 98)? a) 2.0N b) 1.0N c) 0.2N d) 0.1
C
What is the pH of a 0.05 M solution of HCl? a) 1.2 b) 1.4 c) 1.3 d) 1.2
C
Which of the following statements best describes a quality assurance program of clinical laboratories? a) To maintain the high quality patient care by constantly examining every aspect of an entire operation of the hospital that provides the care b) The requirements of quality assurance program of clinical laboratories are regulated by FDA.. c) Check every aspect of the entire testing process including pre-analytical, analytical and post-analytical phases d) Clinical laboratories' delivery of the accurate and reliable testing results promptly to other healthcare professionals
C
Which of the following statements regarding governmental overview of laboratory testing is true? a) Only tests which are FDA approved can be offered. b) Tests very similar to a predicate are not scrutinized by government regulatory agencies. c) Government overview is applied to those tests classified as waived. d) All laboratory tests must be either a predicate or linked to a predicate which has undergone FDA class 3 (PMA) scrutiny.
C
Which of the following best describes quality control in clinical laboratories? a) It covers all policies and procedures of a clinical laboratory. b) It is the same as quality assurance. c) It ensures the test results are reported properly to other health professionals. d) It ensures a particular test method is working properly.
D
Which of the following is a best description of random errors? a) Accurate b) Inaccurate c) Biased d) Imprecise
D
Which of the following is a risk factor of HIV infection? a) Viral load in blood b) Overall health c) CD4 cell count d) Unprotected sex
D
Which of the following best defines analytic sensitivities? a) That concentration of analyte above which is associated with a disease state b) How far a specimen can be diluted before it produces no discernable monitored response c) That concentration of analyte above which would result in no change in the monitored response d) That concentration of analyte that represents the lower limit of the normal reference range
D
A class of 400 college students who have normal blood glucose level and BMI were enrolled in a cohort study to investigate the association between body weight and development of diabetes. The students were followed for the next 40 years. By the time the data were collected, 300 of those students had the BMI of 25 or higher (overweight or obese) and the rest of 100 had the BMI less than 25. Of the 300 with higher than normal BMI, 210 of them had developed diabetes; of the 100 with normal BMI, 5 of them had developed diabetes. What is the odds of developing diabetes among the people who are overweight or obese? a) 44 b) 19 c) 65 d) 2
D
A patient has a new screening test for HIV. The test indicates that the patient is well although he is infected. Which of the following properly describe the test result? a) True negative b) True positive c) False negative d) False positive
D
If a two component mixture has an absorbance of 0.70 at 350 nm and 0.79 at 400 nm, what are the concentrations of compounds A and B in uM units? Assume a 1 cm cuvette and the following: Compound A: λ = 350nm, ϵ = 1 x 104 L/mol∙cm; λ = 400nm, ϵ = 5 x 103 L/mol∙cm Compound B: λ = 350nm, ϵ = 7.5 x 103 L/mol∙cm; λ = 400nm, ϵ = 1.3 x 104 L/mol∙cm What is the concentration of compound A? a) 5.4 x 10-5 M b) 4.4 x 10-5 M c) 2.4 x 10-5 M d) 3.4 x 10-5 M
D
If the new screening test has a sensitivity of 90% and a specificity of 80%. What is the diagnostic efficiency of this test? a) 90% b) 75% c) 80% d) 85%
D
If the prevalence of a disease increases, the sensitivity of the related screening test would change in which of the following ways? a) Could be decrease or increase b) Decrease c) Increase d) Does not change
D
What is the primary factor that would place a product/test/instrument in the FDA Class III? a) Has toxic material b) Has been misdiagnosed as IVD c) Has failed general controls d) No predicate
D
Your laboratory participate a PT for detecting an antibody commonly found in rheumatoid arthritis. You receive five samples and test all five of them positive. Among the fifty laboratories participating the same PT, forty two laboratories use the same testing kit A as your laboratory, and the other eight laboratories use the testing kit B. Among the forty two laboratories using kit A, forty laboratories test the same four samples positive and one sample negative. What is your PT score? a 20 b 100 c 80 d 40
c
