F(3.1): Quality Assurance Flashcards
a management system to direct and control an organization with regard to quality (ISO 9000: CLSI) — systematic and process oriented efforts are essential to meet quality objectives
Quality Assurance
Familiarize the international regulatory bodies in Hematology
- Clinical laboratory improvement amendments (CLIA)
- food and drug administration (FDA) for US
- International organization standard (ISO)
- National accreditation board for testing and calibration laboratory (NABL)
- College of American Pathologists (UKNEQAS, RCPA)
What are the two regulatory bodies of hematology in the Philippines?
- Department of Health and its NRLs (NKTI)
- Philippine Regulatory Commission (PRC)
a. quality
b. reliability
- requires vigilance and effort on the part of all laboratory professionals
- accurate and reproducible
- Degree to which a set of inherent characteristics fulfill requirements
- demonstration of being accurate and reliable over a significant period of time (failure - free)
- B
- A
- A
- B
Fill in the blanks:
The quality of laboratory testing services depends on providing the ______________ and _______________ that conform to the stated or implied needs of customers or customers
*totality of features
*characteristics
- set of activities for ensuring quality in the processes by which products are developed
- process oriented and focuses on defect prevention
- systematic lab program, encompassing pre ana, ana, and post ana factors
- sum of all the activities in the lab to ensure that the info generated are correct
Quality assurance
- a component of quality assurance
- set of activities for ensuring quality of the products (by detecting, evaluating, and correcting errors that may be caused by system failure, environmental condition, or operator performance)
- product oriented and focuses on defect identification
Quality control
a. quality assurance
b. quality control
- establishing a good quality management system and assessment
- Identify and correct defects in the finished product
- Finding and eliminating sources of quality problems through tools and equipment
- A
- B
- B
a. quality assurance
b. quality control
- Prevent defects with a focus on the process used to make the product
- To identify defects after a product is developed and before it’s released
- To improve development and test processes so that defects to not arise when the product is being developed
- A
- B
- A
A. preanalytical
B. analytical
C. post analytical
- Laboratory staff competence
- assay and instrument selection
- assay and instrument validation, including linearity, accuracy, precision, analytical measurement range (AMR), and specificity
- internal quality control
- external quality assessment
B
A. preanalytical
B. analytical
C. post analytical
- accurate transcription and filing of results
- content and format of laboratory report
- narrative report
- reference interval (RI) and therapeutic range
- timeliness in communicating critical values
*patient and physician satisfaction
*turn-around-time
*cost analysis
*physician application of laboratory results
*patient outcome
C
A. preanalytical
B. analytical
C. post analytical
- assay selection based on patient indication
- implementation of assay selection
- patient identification and preparation
- specimen collection
- equipment and technique
*specimen transport, preparation, and storage
*monitoring of specimen condition
A
match the preanalytical component to the laboratory staff responsibility (no choices kaya niyo na yan malaki na kayo :>)
- Are the specimens delivered intact, sealed and within specified time limits? Are specimens maintained at the correct temperature?
- Do turnaround time expectations match clinical necessity and ensure that stat orders are reserved for medical emergencies? Does laboratory management meet established turnaround time requirements?
- Specimen transport
- Stat orders and timeliness
match the preanalytical component to the laboratory staff responsibility (no choices kaya niyo na yan malaki na kayo :>)
- Conduct continuous utilization reviews to ensure that physician-generated orders are comperehensive and appropriate to patient indications. Inform physician about laboratory test availability and ways to avoid unnecessary orders. Reduce unnecessary repeat testing
- Are specimens centrifuged correctly? are tests begun within specified times? Are specimens and aliquots stored properly? Are coagulation specimens consistently platelet-poor?
- Test Orders
- Specimen management
match the preanalytical component to the laboratory staff responsibility (no choices kaya niyo na yan malaki na kayo :>)
- Is the patient correctly identified, prepared, and available for specimen collection? Is fasting and therapy status appropriate for the assay? Is the tourniquet correctly applied and released at the right time? Are venipuncture sites properly cleansed? Are timed specimens collected at the specified intervals? Are the specimen tubes collected in the specified order? Are additive tubes properly mixed? Are specimen tubes labeled properly?
- Are requisition forms legible? Can the phlebotomist confirm the patient identity? Are physician orders promptly and correctly interpreted and transcribed? Is adequate diagnostic, treatment, and patient preparation information provided to assist the laboratory staff to appropriately test and interpret results?
- Specimen collection
- Test request forms
Match the Post analytical Quality assurance to the laboratory staff responsibility
Are results accurately transcribed into the information system?
Are they reviewed for errors by additional laboratory staff? If autoverification is in effect, are the correct parameters empolyed? Do reports provide reference intervals (RIs)? Do they flag abnormal results? Are result narrative appended when necessary? Does the laboratory staff conduct in-service education to support test result interpretation? Are critical values provided to nursing and physician staff? Are verbal reports confirmed with feedback? Are anomalous findings resolved?
Publication of reports
Match the Post analytical Quality assurance to the laboratory staff responsibility
- Are turnaround times recorded and analyzed? Are laboratory reports being posted to patient charts in a timely fashion?
- Does the institution include laboratory care in patient surveys? Was specimen collection explained to the patient?
- timeliness
- patient satisfaction
- analytical measurement or testing used to assess the quality of data
- a system of ensuring precision and accuracy in the lab by using quality control reagents in every series of measurement
- high, low pathologic, and normal level
- should be done during every shift
- depends on quality policy of labs
Quality control
a. Internal QC
b. External QC
- process that monitors accuracy and precision of test results
- performed daily
- proficiency testing samples
- feedback is not immediate
- A
- A
- B
- B
a. Internal QC
b. External QC
- method that allows lab to evaluate its performance against a benchmark or external source
- performed periodically
- feedback is quick
- concentrations are unknown
- B
- B
- A
- B
a. Internal QC
b. External QC
- used for immediate decision
- handle proficiency testing samples in the same way as patient samples
- concentrations are known
- A
- B
- A
What are the three objectives of quality control
- check the stability of the machine
- check the quality of the reagents
- check technical (operator) errors
- if the test to detect the smallest amount or concentration of analyte in a sample
- measuring the minute concentrations of an analyte
sensitivity
- coupled with linearity and AMR (analytical measurement range) studies, and are required of local laboratory professionals when modifying an FDA-approved assay or developing an LDT
*this limit prevents false-positive results generated by low-end assay interference, commonly called noise
(lower limit detection, LLD)
- test must always give a positive result in the presence of a disease
- evaluates the capacity of the test
Diagnostic sensitivity
- ability of a test or a method to measure only the specific analyte of interest without the interferences of other substances present in the sample
- ability of an assay to distinguish the analyte of interest from anticipated interfering substances within the specimen matrix
Specificity
a. analytical specificity
b. diagnostic specificity
- gives a negative result in the absence of the disease
- measuring only one unknown substance of interest
BA
a. positive predictive value
b. negative predictive value
- proportion without a disease who have a negative test result compared with all individuals who have a negative test result
- proportion with a disease who have a positive test result compared with all individual who have a positive test result
BA
a. positive predictive value
b. negative predictive value
- predicts the probability that subjects or patients with a positive screening tests truly harbor the disease
- predicts the probability that subJects or patients with a negative screening tests truly does not have the disease
AB
- Measurement of agreement between the assay value and the theoretical “true value” of its analyte
- the ability of a method to determine the exact value of a particular substance or analyte of interest
- How close or how near you are to the test value
accuracy
ability to produce the same results in unchanged condition (repeatability) or in changed condition (reproducibility)
precision
familiarize the four scenarios under precision
- low accuracy, low precision
- low accuracy, high precision
- high accuracy, low precision
- high accuracy, high precision
degree by which a method could be easily repeated
practicality
What are the parameters to be evaluated by the laboratory manager?
- assay throughput (the number of assays per unit time)
- dwell time (length of assay interval from specimen sampling to report)
- cost per test
- cost / benefit ratio
- TAT
- technical skill to perform the assay
ability of an analytical method to maintain accuracy and precision over an extended period of time
reliability
LINEARITY ANALYTICAL MEASUREMENT RANGE
During assay runs, patient specimens with results above the linear range must be ____________ and _____________
diluted and reassayed
LINEARITY ANALYTICAL MEASUREMENT RANGE
Where is the acceptable range of linearity established?
just above the low value and below the high value
LINEARITY ANALYTICAL MEASUREMENT RANGE
how many dilutions of standard / calibrator must be prepared?
at least 5
an occurrence or an event that have negative impact on laboratory which includes the personnel, patient results, machine, or the environment
LABORATORY ERROR
- involves running known samples with anticipated results to monitor the accuracy and precision of testing procedures
- can either be included in the test kits or third party
INTERNAL QUALITY CONTROL
T or F
control samples are only sold in liquid form
f ( can be lyophilized or powdered form)
- aka PROFICIENCY TESTING
- participating in proficiency testing programs allows laboratories to assess their performance against established standards
EXTERNAL QUALITY CONTROL
- Done by comparing one instrument reading to a known physical constant
- maintains accuracy and reliable test results
INSTRUMENT CALIBRATION
- By chance - the same mistake may not be made again
- results in inconsistent measures (poor precision, non-specific, not reproducible)
- there is no identifiable trend or means of predicting
- affects the precision performance of the test
RANDOM ERROR
- Predictable and happen all the time
- results may remain constant
- they show trend in the data
- affects accuracy (poor accuracy)
SYSTEMATIC ERROR
a. random error
b. systematic error
- Westgard rules violtions: 1(2s); 1(3s); and R(4s)
- westgard rule violation: 2(2s); 4(1s)
AB
a. random error
b. systematic error
- Improper calibration of equipment
- mislabeling of samples
- pipetting errors
- possible deterioration of reagents
- A
- B
- B
- A
a. random error
b. systematic error
- improper mixing of samples / reagents
- voltage fluctuations
- sample instability
- B
- B
- A
a. Reassay
b. Prepare new control
c. Prepare fresh reagents and reassay
d. Recalibrate instruments
- When a limit of 2± SDs is used, 5% of expected assay results fall above or below the limit
- Instrument may require repair
- Reagents may have evaporated or become contaminated
- Controls may deteriorate over time when exposed to adverse temperatures or subjected to conditions causing evporation
- A
- D
- C
- B
- Provides criterion for judging whether an analytic process is out of control
- Series of internal QC rules for long-term deviations.
- Developed for assays employing primary standards.
- Useful in hematology and hemostasis laboratories.
westward multi-rule system
westward multi-rule system
The rules are divided into two categories:
Control rules
Warning rules
westward multi-rule system
- Description automatically generatedThe control limits are set as the mean plus 3s and the mean minus 3s.
- A run is rejected when a single control measurement exceeds the mean plus 3s or the mean minus 3s control limit.
- Random error
13S
westward multi-rule system
- 1 contol outside 2SD
- Either + or - side
- random error
- In the original Westgard multirule QC procedure, this rule is used as a warning rule to trigger careful inspection of the control data by the following rejection rules.
12S
westward multi-rule system
Do you accept or not?
- In the original Westgard multirule QC procedure, this rule is used as a warning rule to trigger careful inspection of the control data by the following rejection rules.
Accept
12S
westward multi-rule system
2 consecutive control measurements exceed the same mean plus 2s or the same mean minus 2s control limit.
Systematic error
Reject
22S
westward multi-rule system
- Description automatically generated2 consecutive control value outside 2SD on opposite sides
- Random error
- Reject when 1 control measurement in a group exceeds the mean plus 2s and another exceeds the mean minus 2s.
- This rule should only be interpreted within-run, not between-run.
- The graphic below should really imply that points 5 and 6 are within the same run.
R4S
westward multi-rule system
- Description automatically generatedReject when 10 consecutive control measurements fall on one side of the mean.
- Systematic error
10x
steps used to correct an out-of-control assay run
When a limit of 2SD is used
5% of expected assay results fall above or below limit
re-assay/retest
steps used to correct an out-of-control assay run
Controls can deteriorate overtime when exposed to adverse temperatures or subjected to conditions causing evaporation
preparation of new control and re-assay
steps used to correct an out-of-control assay run
Reagents may have evaporated and become contaminated
Reagents may have evaporated and become contaminated
steps used to correct an out-of-control assay run
steps used to correct an out-of-control assay run
recalibrating instruments
- Coordinated activities to direct and control an organization with regard to quality (ISO and CLSI definition)
- A method of detecting errors at each phase of testing is needed if quality is to be assured
quality management system
A. Pre-examination
B. Examination
C. Post-examination
- Patient/client preparation and sample collection
- Personnel competency and test evaluations
- Sample receipt and accessioning
- Sample transport
A
A. Pre-examination
B. Examination
C. Post-examination
- Reporting
- Record keeping
C
A. Pre-examination
B. Examination
C. Post-examination
- control testing
B
involves procedures to assess laboratory work and emergent results continuously.
Internal Quality Control (IQC)
Involves examining control materials of known substances alongside patient samples to monitor the accuracy and precision of the entire analytic process.
Quality Control
Focuses on activities related to the examination (analytic) phase of testing.
Monitoring
To detect, evaluate, and correct errors due to test system failure, environmental conditions, or operator performance before patient results are reported.
Goal
- Measures the quantity of an analyte present in the sample
- Measurements need to be accurate and precise
- Measurement produces a numeric value as an end-point, expressed in a particular unit of measurements
- Example: blood glucose = 5 mg/dL
quantitative examinations
- Measures the presence or absence of a substance or evaluate cellular characteristics such as morphology
- Result are expressed in qualitative terms
qualitative examinations
- Results are expressed as an estimate of how much of the measured substance is present
- Expressed in term such as “trace amount”, “moderate amount”, or “1+, 2+, or 3+”
- nvolves a number but provides an estimate, rather than an exact amount of the quantity present
semiquantitative examinations
FAMILIARIZE
elements of a quality control program
- Establishing written policies and procedures, including corrective actions
- Training all laboratory staff
- Ensuring complete documentation
- Reviewing quality control data
FAMILIARIZE
steps in implementing a quality control program
- Establishing policies and procedures
- Assign responsibility for monitoring and reviewing
- Train all staff on how to properly follow policies and procedures
- Select good QC material
- Establish control ranges for the selected material
- Develop graphs to plot control values (Levey-Jenning’s chart)
- Establish a system for monitoring control values
- Take immediate corrective action if needed
- Maintain records of QC results and any corrective actions taken
laboratory practices on assuring quality
Activities done prior to the examination of specimen or sample and are intended to establish systems conducive to accuracy in analytic systems such as:
preventive
laboratory practices on assuring quality
Activities done during the testing to determine whether the test systems are performing correctly such as:
assessment
laboratory practices on assuring quality
Activities done when an error or possible error is detected to correct the system such as:
corrective
A. Quantitative
B. Semiquantitative
- Urine dipsticks, tablet test for ketones
- Serologic agglutination procedure
- Serologic testing result expressed as a titer
B
- Microscopic examinations
Positive or negative
Normal or abnormal - Serologic procedure for presence or absence of antigens and antibodies
Reactive or nonreactive - Microbiological procedures
Growth or no growth
qualitative examinations
ubstances that contain an established amount of the substance being tested. Analyte tested at the same time and in the same way as patient samples
control materials
TYPES OF CONTROL MATERIALS
- frozen
- Freeze-dried
Sources of control material
- Purchased
- obtained from a central or reference laboratory
- Made in-house by pooling sera from different patients
control materials vs calibrators
a. controls
b. calibrators
- used to detect systematic errors independently of the calibration process
- adjust or revalidate insturmentation and develop calibration curves
- a
- b
- Also called standard
- Are solutions with a specified defined concentration that are used to set or calibrate (to provide the reference point in measuring a test) an instrument, kit, or system before testing is begun
- Should not be used as controls since they are used to set the instrument
- Function: After calibration, a control is run to ensure the instrument is within an acceptable range.
- Usually do not have the same consistency as patients’ samples
calibrators
- Inexpensive and prepared from the same matrix as patient specimens.
- Include preservatives, lyophilization, or freezing to prolong shelf life.
- Provide known values and are sampled alongside patient specimens for within-run assay validation.
control materials
Control usage
- how many controls are required per test run?
- when should controls be run
- two controls ( reference interval and above reference interval)
- once per hift
establishing the value range for the control material
One or two data points that are significantly different from the cluster of acceptable values.
outliers
- Commonly used to represent the control range graphically for the purpose of daily monitoring
- Shows the mean value as well as +/- 1, 2, and 3SD
- Displays control results compared with the mean and limits.
- Assumes Gaussian distribution and imprints limits at 1, 2, and 3 SD above and below the mean.
- Analyzes single-run and long-term control variation
levey-jennings chart
