Quality Assurance Flashcards
Importance of Quality Control
- for accurate lab results
- efficient lab operations
- timely reporting of info
- customer’s needs and satisfaction
Phases of QC
Pre-analytical phase
Analytical phase
Post-analytical phase
- serum indices
- monitor the ability of an instrument to detect hemolyzed, icteric, or lipemic samples
Pre-analytical phase
- quality control
- comprehensive line of independent QC products to monitor precision
actual measurement of the analyte in a specimen
Analytical phase
Informatics
- QC Data management and analysis
- Unity Software Solutions
- Interlaboratory peer group comparison program
Post-analytical phase
- refers to all the processes a lab takes to ensure quality of test results
- result of all such processes
Quality Assurance
How is QA achieved?
by planning, assessment, monitoring tools to pledge, guarantee, and assure that the results produced are correct and reliable
establishment of quality requirements to satisfy customers
Quality Assurance Program or Quality Management Framework
encompasses the creation, selection, and validation of methods and processes in the lab
Quality Planning
result from quality planning and describe the means by which work is conducted in the laboratory
Quality Laboratory Process (QLP)
personnel policies, standard operating procedures, specimen collection guidelines
QLP
represent the best way work is done in the lab
QLP
all actions done to measure & monitor performance of the lab processes
Quality Assessment
- verification of the quality of sample collected
- sample processing
- reporting of results
- competency & adequacy of lab staff
Quality Assessment
thorough assessment of what the problem is and the use of quality planning to modify and/or create lab processes to eliminate the problem
Quality Improvement
provides tools to detect problems early and prevent errors from exceeding established quality requirements
Quality Control
What are the 5 Q’s of the Quality Assurance Program?
Quality Planning Quality Laboratory Processes Quality Control Quality Assessment Quality Improvement
component of QAP which is comprised of all systematic actions needed to produce adequate confidence that lab services will give the medical needs for patient care
Quality Control
- the process of monitoring lab analyses to ensure accuracy of results
- system set to ensure that certain limits for test results are maintained
Quality Control
In what phase does QC apply to?
Analytical phase
ISO standard that requires labs to create measurable objectives that can be assessed to determine the success of the quality system
ISO 9001
What are the ISO 9001 quality indicators?
- customer satisfaction
- conformity to customer requirement
- a count of preventive actions addressed
- quality materials provided by suppliers
ISO standard for the particular requirements for quality and competence
ISO 15189 Med Lab 2007
ISO standard for the general requirements for competence of testing and calibration labs
ISO/IBC 17025, 2005
ISO standard that requires labs to implement quality indicators to systematically monitor & evaluate the lab’s contribution to patient care
ISO 15189
What are the characteristics of a good quality control?
SPARPS
- Specificity
- Precision
- Accuracy
- Reliability
- Practicability
- Sensitivity
the closeness of an analytical result to the true value
Accuracy
- reproducibility
- the degree to which repeated result agree
the closeness of test results to each other
Precision
How is precision expressed?
by standard deviation
True or False
- the larger the standard deviation, the precise the values are
False, smaller sd
the ability of the method to detect even the smallest amount of the substance tested
Sensitivity
the ability of a method/instrument to detect a particular substance w/o the interference of some other substances present in the sample
Specificity
the ability of a method/instrument to maintain its accuracy & precision even at an extended period of time or under different variables
Reliability
the degree to which the method/instrument is easily repeated
Practicability
What are the purposes of Quality Control?
To check:
- the stability of the equipment
- the quality of the reagent
- technical errors
- the lab results
What are the 2 major divisions of QC Program?
- External QC (Interlaboratory)
- Internal QC (Intralaboratory)
DOH Memo No. 2009-0086
Implementation of External Quality Assessment Program as Regulatory Requirement for Licensing of Clinical Laboratories
a substance/chemical of known exact value used to calibrate an assay method
Standard
substances of the highest possible quality and accuracy
Primary Standards
controls developed in comparison with primary standards
Secondary Standards
- a substance w/ a particular value that has been determined/assigned by the manufacturer
- used to adjust an instrument to certain values prior to running samples
Calibrator
- a substance which contains the same analyte that is being tested for and assayed by he usual clinical lab methods
- has a certain nominal range and is treated like a patient sample
QC Sera (QCS/QCM)
What is assayed together with QCS? What is the purpose?
the unknown sample, to measure precision
Choices of QCS is dependent on:
- availability of QCS that contains the analyte
2. nature of liquid matrix (of the source)
2 Sources of QCS
Human and Animal
Most common animal QCS source
Bovine
Types of QCS
- In-House/Non Commercial
2. Commercial QCS
Examples of Non commercial QCS
- pooled sera
- fasting donor sera
- blood bank plasma
2 Kinds of Commercial QCS
Assayed QCS
Unassayed QCS
Commercial QCS with a control value/known concentration that has been pretested using analytical procedures by the manufacturer, usually more expensive and used frequently
Assayed WCS
Commercial QCS which is less costly and the values are known but not given, usually have target values w/ actual results falling near the target value
Unassayed QCS
2 Forms of Commercial QCS
Lyophilized form (powdered) Non-lyophilized form (liquid)
True or False
QC samples must be analyzed with patient samples using the same method and conditions but different reagents.
False, the same reagents
True or False
QC samples should be run once a day, if possible routinely in each analytical run
True
True or False
QC samples need not be run after an instrument has already been calibrated
False, should be run after calibration
True or False
QC samples should be evaluated during a 30-40 day period
False, 20-30
True or False
QCS results are used to create a Quality Control Chart
True
a statistical tool which is a typical representative value of a set of observations
Mean
True or False
Mean is the best way of expressing the validity of a series of results
False, it’s a poor way
- the measurement of variation of a single result from the mean
- the spread of any value from the mean
Standard deviation
- statistical tool used to compare the relative variability between 2 or 3 different sets of values
- degree of dispersion of data points relative to the mean
Coefficient of Variation
statistical tool used to determine precision from one test method to the other
Coefficient of Variation
True or False
Precise methods have a CV of < 5%
True
statistical tool used to distinguish between normal and abnormal values at the borderlines of the normal range
Allowable Limits of Error (ALE)
True or False
The ALE concentration units must be lesser than half of the normal range
False, greater than 1/4 of the normal range
Types of Graphical Displays
Bar graphs
Pie graphs
Line Graph
chart that displays the control observation/calculated statistic as a function of time (date, run number) and uses a rectangular coordinate paper to plot values
Control Chart
Examples of control charts
- Yuoden Plot/Twin Plot Chart
2. Levey-Jennings/Shewhart Chart/Dot Chart
labelled with the mean and appropriate SD values at line intersection points on the Dot Chart
Y-axis
labelled from left to right in time unites that reflects the sequence of control measurements on the Dot Chart
X-axis
a technique with a set of criteria as useful as the Levey-Jennnings Chart for monitoring performance
Westgard “Multirule” Technique
Purposes of the Westgard rule
- to improve quality monitoring
- to minimize subjectivity in data analysis
- to provide help or guide in trouble shooting
technique that can be performed on quality control data using the L-J graph
Trend Analysis
True or False
Lean optimizes space, time, & activity to improve chemical paths of workflow/
False, physical
Lean Processes
- identify the value
- map the value stream
- create flow
- establish pull
- seek perfection
technique that uses a formal project planning structure that moves the process of reducing error to the lowest levels in the organization
Six Sigma
5 Steps Cycle of Six Sigma
Define Measure Analyze Improve Control
True or False
Six Sigma is any process that can be evaluated in terms of sigma metric (how many sigma’s fit within tolerance limits)
True
2 methods of Six Sigma
- measure outcomes by inspection
- measure variation & predict process performance
a symmetrical bell shaped curve generated when plotting samples values on a graph wherein the assay values are on the x-axis and the frequency of each value are on the y-axis
Gaussian Curve
percentage of values that falls within ± 2SD in a normal distribution curve
95.5%
percentage of values that falls within ± 1SD in a normal distribution curve
68.3%
If the values are farther from the mean, the curve would be _____ compared to the normal distribution curve
Lower
If the values are closer to the mean, the curve would be _____ compared to the normal distribution curve
Higher or more pointed
A good rule of thumb is that data sets should contain at least ___ points.
20
a graph wherein quality control data is plotted on to give a visual indication whether a lab test is working well
Levey-Jennings Chart
When the QC values obtained are within ±2SD, you are ___ control
In
the gradual change, increase or decrease, of 4 or more consecutive QC values from the mean
Trend
a change that becomes systematic & continuous which occurs when 4 or more consecutive QC values point apart on the same side of the mean
Shift
an increased frequency of both high and low outliers
Dispersion
When does an increased dispersion occur?
When there is imprecision
a QC value that exceeds ±3SD
Outlier
an imprecision/random variance error due to chance and does not cause a change of accuracy
Random Error
True or False
a random error source is easy to identify through QC, however specific problems are hard to pinpoint
True
an inaccuracy/variance error which may influence results to be consistently higher or lower than the real value
Systematic Error