Mid 1 LO1 -LO3. 7 Flashcards

(141 cards)

1
Q

Why do we need to take QC 194?
3

A

quality control, management, assurance

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2
Q

laboratory quality 3 key words

A

accuracy, reliability and timeliness

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3
Q

Quality is defined as

A

excellence

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4
Q

What is Quality Assurance?

A

all the actions a laboratory takes to ensure quality results

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5
Q

laboratory errors cost in 3 things

A

time
personnel effort
poor patient outcomes

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6
Q

inaccurate results provided lead to these consequences

A
  • Unnecessary treatment
  • treatment complications
  • failure to provide the proper treatment
  • delay in correct diagnosis
  • additional and unnecessary diagnostic
    testing
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7
Q

achieving 99% level of quality =

A

accepting a 1% error rate

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8
Q

In order to achieve the highest level of accuracy & reliability it is essential to

A

perform all processes and procedures in the
laboratory in the best possible way

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9
Q

A Quality Management System for the Laboratory

is what type of method

A

A method of detecting errors at each phase of testing is needed if quality is to be assured

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10
Q

ISO standards dos what

A

groups the laboratory system into 3 categories

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11
Q

laboratory systems the 3 categories by the ISO

also called The quality assurance cycle

A

Preexamination, Examination, Postexamination

= Pre-Analytic, Analytic, and Post-Analytic processes

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12
Q

Quality system essentials : The building blocks/ 12 QSEs= how we achieve excellent performance

what are the 3 sub categories

A

The lab
The work
Performance

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13
Q

Quality system essentials : The building blocks/ 12 QCs

The lab : 6 subs

A

-Organization
-customer focus
-facilities and safety
-personnel
-purchasing and inventory
-equipment

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14
Q

Quality system essentials : The building blocks/ 12 QCs

The work: 3 subs

A

-Process management
-Documents and records
-information management

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15
Q

Quality system essentials : The building blocks/ 12 QCs

performance: 3 sub

A

-nonconformance managements
-assessments
-continual improvement

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15
Q

Quality system essentials : The building blocks/ 12 QCs

performance: 3 sub

A

-nonconformance managements
-assessments
-continual improvement

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16
Q

Quality Management System
what does it do
international vs Canada

A

= Coordinated activities to direct and control an organization with regard to quality (ISO-international, CLSI-Canada)

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17
Q

Path of Workflow: 5

A

The patient
test selection
sample collection
sample transport
repost creation

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18
Q

what is the path of workflow accessing ? important in

A

validity

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19
Q

QSEs
1. Organization

A

-must be structured
-Responsibilities, authorities
-provision of recourses
-communication

ex
following governing bodies for Structure
Quality planning - reports, improvement process
Communication -huddles, documents, reports

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20
Q

QSEs
2. Customer service

A

clinicians, patients

-customer feedback documented and analyzed
-informing costumers of changes
-costumers can email concerns
-safety alert system that both can report to

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21
Q

QSEs
3. Facilities and Safety

A

-safe working environment
-transport management
-security
-containment
-waste management
-laboratory safety
-ergonomics

ex
having safety committees and governing bodies
-biohazard safety/ disposal
-having codes in emergencies/ colors
-chemical hygiene

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22
Q

which ISO safety standards number regulates safety regulations

A

15190

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23
Q

number too make a safety issue report

A

306 655 1600

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24
QSEs 4. Personnel
* Human resources * Job qualifications * Job descriptions * Orientation * Training * Competency assessment * Professional development * Continuing education * SOPs (standard operating procedures) * Work logs * confidentiality
25
what does HIPA stand for
Health Information Protection Act
26
QSEs 5. Purchasing and Inventory
* Vendor qualifications * Supplies and reagents * Critical services * Contract services * Contract review * Inventory management -documentation - proper returns in case of defects
27
QSEs 6. Equipment
* Acquisition * Installation * Validation * Maintenance- scheduled and loged * Calibration * Troubleshooting * Service and repair * Documentation/records * Procedures * Running controls -operation life cycles -justifying needs for equipment -decommissioning
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QSEs 7. Process control
* Quality control * Sample management * Method validation * Method verification pre-analytic, analytic, post analytic The phases include patient preparation and proper identification, sample collection requirements, control samples, calibrators, reagents and equipment performance, correlation of test results and proper entry of patient results into the computer system for the physicians.
29
how long is the turn around time
1 hr
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QSEs 8. Documentation and Record Keeping
Laboratory information is permanent and cannot be tampered with unless signed or initialed, therefore, record keeping is a legal responsibility under government regulations and should be confidential, yet easily retrieved for use by the accreditation team. As well, log books are kept for maintenance, temperatures of fridges, water baths, incubators etc. for specific periods of time, determined by accreditation and federal regulations. -Collection -review -storage -retentions
31
QSEs 9. Information Management what important groups is under here
laboratory information systems LIS incorporates all the processes necessary to manage incoming and outgoing patient information using unique identifies (patient and samples) and limits who can access the confidential information which is protected by law * Confidentiality * Requisitions * Logs and records * Reports * LIS -against loss of data -testing info -sharing documents not using email -secure and monitored access -planning for information needs -integrity of data transfers or transmission -information availability during downtown -analysis, design, and documentation of lab processes -verification and validation of lab processes -quality control of lab process -managing and controlling changes in lab processes
32
QSEs Performance block Nonconformance management 10. Occurrence management
-An error or event that should not have happened -complains -mistakes and problems -root cause analysis -immediate actions -corrective actions -preventative actions example of dealing: recognize, report, initiating, documenting call in safety issues ,management notification of reports
33
QSEs 11. Assemnents
Laboratory assessment = a tool for examining laboratory performance and comparing it to standards or benchmarks of the performance of other laboratories. May be internal or external ISO (Internal Standards Organization) – requires accredited laboratory auditors to compare results from similar laboratories to assess laboratory performance. Audits may be internal or external mainly accreditation inspections related proficiency testing for test accuracy
34
QSEs Continual improvement 12. Process improvement
-The deming cycle -PDCA cycle : Plan, Do, Check, Act -prioritization -impact vs effort assements -protective and corrective actions -problem resolutions Lab 1st identifies issues then gathers the info…a plan is made for improvement…plan implemented…data gathered and assessed…plan is updated..corrective action is taken to ensure plan effective ..then process begins cycle again
35
who are labs audited by
ISO (Internal Standards Organization)
36
who conducts the accreditations inspections
the college of physicians and surgeons CPSS you get a certificate of accreditation every 305 CPSS and every 2 years ASHI
37
T/F QSES does not gurantee and error free lab
T
38
T/F ISO and CLSI are compatible
T
39
ISO 9001:2015
Quality Management System- Requirements
40
ISO/IEC 17025:2017
General requirements for the competence of testing and calibration laboratories
41
ISO 15189:2012
Quality management in the clinical laboratory
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QMS01
A Quality Management System Model for Laboratory Services This guideline provides a model for medical laboratories to organize the implementation and maintenance of an effective quality management system
43
Quality
in Learning Step 1 was defined as "degree of excellence". It can now be expanded and clarified to "providing consistent services which meet or exceed the needs of the customers (patients)''
44
A benchmark
serves as the standard of excellence or performance level against which a process, in this case laboratory service, is measured. If the service does not meet a certain benchmark, then the quality must be improved
45
Continuous Quality Improvement Program (CQI)
is the activity associated with improving the laboratory's ability to constantly improve the quality of the lab processes.
46
Quality Management Systems (QMS)
) can be defined as the "achievement of quality as a continuous process involving all personnel at all levels of an organization in the pursuit of excellence in every process, with the ultimate objective being quality patient care". To facilitate QMS, all employees must be empowered and tools to assist in measuring variation in lab results (preventative & corrective) tools to evaluate statistics and to continuously find ways to improve procedures and comply with accreditation expectations.
47
Empowerment
means providing staff with opportunities, the authority and resources to settle quality issues in which they are directly involved.
48
Accreditation
is a non-governmental, external, peer review process for assessment of healthcare facilities, laboratories or educational programs against a certain benchmark. It provides a professional judgement about the quality of the facility and encourages continued improvement. It also provides a good indication to the public that each accredited facility is capable of functioning at the required level of competence.
49
ISO 15189 Accreditation
Standards must be met for an organization to be accreditedà Accreditation Canada (AC) Diagnostics accreditation program assess the ability of a facility to perform diagnostic testing with formal recognition of this competence through accreditation to the ISO 15189 Plus requirements.
50
Laboratory Quality Assurance Program (LQAP) administrated by whom
College of Physicians and Surgeons of Saskatchewan * The Laboratory Quality Assurance Program (LQAP) is responsible for establishing the requirements and standards of medical laboratories in the province of Saskatchewan and to ensure their compliance with the Medical Laboratory Licensing Act and Regulations * The LQAP consists of two types of committees comprised of medical and technical experts in the relevant discipline
51
Internal Quality Assurance Procedures
* Internal quality assurance à focused around testing of patient clinical samples * Monitoring is by the facility or department so then internal
52
review pre -post analytical images that have many ex
53
External Quality Assurance Programs
* EQA is used to evaluate laboratory testing accuracy * EQA tools are shipped from the provider directly to the laboratories on a rotational basis. Testing is performed in the same manner as a patient specimen. * LQAP mandates that EQA assessments be performed for all tests * EQA providers for Saskatchewan are: * The College of American Pathologists (CAP) * One World Accuracy * Clinical Microbiology Proficiency Testing (CMPT) * American Proficiency Institute (API)
54
Quality Assurance Audit
* Provides the lab with knowledge of how well it follows its own quality control program * By conducting its own internal quality audit assures that the lab is providing reliable results. It assesses the validity of the results. * It is achieved by reviewing daily QC data in the lab as well as cumulative reports over a time frame
55
Continuous quality improvement
* PDSA cycle * Continually asking questions every step of every process in the laboratory to see if there are ways to improve eg) speed up processes/improve * Huddle/meeting discussions, safety alert system reviews, audit reviews, staff suggestions
56
CLSI vs ISO
Non-profit organization that brings together the varied perspectives and expertise of the worldwide laboratory community for the advancement of a common cause -developed the quality management system model used in training for QMS and is fully compatible with ISO vs * An international standard dedicated to Quality Management Systems (QMS) -established standards for industrial manufacturing
57
problem solving process the MC in test IOS MED
1 Input: A phlebotomist complains that inpatients are never properly identified. 2 Occurrence Indicator: The phlebotomist finds an inpatient without a wristband. 3 Standard: All inpatients must have wristbands when they are admitted to hospital. No procedure will be performed on a patient unless they have a wristband. 4 Monitor : Effective immediately, the number of patients without wristbands will be counted for the next 30 days by the phlebotomy team. 5 Evaluate : The lab supervisor will evaluate the data and give her recommendations to the nursing supervisor. 6 Document: The lab supervisor will document the entire process including the results from monitoring, recommendations for further action, and the results of any corrective action that was taken.
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Occurrence or Non-Conforming Event Evaluation should include:
problem description, action plan, monitoring, summary of results and recommendations, correct the problem.
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RRID
Recognizing * Recognize when a reportable even occurs * Reporting * Report the even to appropriate person * Initiating * Initiate corrective action * Documenting * All events and their corrective action must be documented
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LO2 begins Pre-Analytical Variables what minimizes them
* Factors that can affect patient’s test results before the specimen is tested in the lab. * QA minimizes this risk before testing
61
Policy Manuals
* Outline administrative and operational issues * Ensures effective communication * Everything must be documented * Ensures a standard of quality in the work * Policy manuals are a useful tool for how the lab should be organized and complete
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Laboratory Logs LIS
* Internal manuals or computerized records of patient specimens arriving at a specific department * LIS = Laboratory Information Systems
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Procedure manuals
SOPs (standard operating procedures) step by step instructions on how to perform something
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TAT or Turn around time
* = time sample collected to when result released * This is also monitored/data assessed and helps identify problems, corrections and can affect patient treatment
65
What are the two most important steps before collecting a patient specimen?
1. Patient Identification 2. Patient Preparation
66
Calibrators are
solutions with an exact known concentration of analytes * Used to adjust systems to an established reference method * How? The instrument measures the calibrator and adjusts the signal to match the given values. Plotting the signal on the Y-axis versus analyte conc. on the X-axis creates a calibration curve. The purpose of a calibration curve is to establish the relationship between the conc. of analyte and the magnitude of the signal given by the measuring device. (linear or non-linear)
67
Standards
can be considered calibrators, but they are usually a pure chemical whereas calibrators usually have several exact known analytes in a similar matrix to what is being tested (ie. Serum or plasma).
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Controls
are substances which contain one or more known analytes which are used to verify the accuracy and precision of measurements. They can be biological or synthetic in nature. * A patient-like material ideally made from human serum, urine or spinal fluid. * Should be tested in the same manner as patient samples * Known ranges * Usually contains many different analytes in one bottle * Good laboratory practice requires testing normal and abnormal controls for each test at least daily to monitor the analytical process * QC statistics are recorded on LJ charts, and Westgard Rules are considered
69
Precision
refers to the reproducibility of a result or how often the same result is generated by repetitive testing. * Can indicate random errors but it does not indicate that an instrument is reporting the correct result, which is accuracy For example, a technologist may be required to pipet 2 mL of deionized water into 30 test tubes. If the technologist's skill is precise, all 30 tubes will contain exactly 2 mL of water.
70
Accuracy Who are the only one who has it
infers the correctness or closeness with which the measurement comes to the true value. Only calibrators/standards have accurate or true values. For example, a solution may be known to contain 2.5 to 2.9 mmol/L of a substance. If the substance is analyzed, a determined value of 2.6 mmol/L would be considered accurate, while a value of 4.0 mmol/L would not be accurate.
71
Reliability refers to a
degree of accuracy and precision over an extended period of time under variable conditions. -Accuracy & precision reflect how well the test method performs day to day in the lab. The other two, sensitivity and specificity, deal with how well the test is able to distinguish disease from absence of disease. For example, the VW Beetle which drove well with few problems over several years of ownership, demonstrating accurate and precise driving capabilities, was considered to be a “reliable” car.
72
Specificity
infers the ability to accurately measure one component without interference by other components. * Specificity is the ability of a test to correctly exclude patients who do not have a given disease. The more specific the test is, the less false-positive results For example, if one were interested in eating only the red candies in a box of Smarties, one would not want to pick any other colour, such as purple, green, blue, etc. When evaluating a method in the clinical lab we use negative controls to assess specificity.
73
Negative controls
are samples which are lacking in the component we are interested in detecting. If the method is specific and a negative control is tested, our test result should be negative.
74
Sensitivity
infers the ability to measure small amounts of a component. * Sensitivity is the ability of a test to correctly identify patients who have a given disease or condition. The more sensitive a test, the less false-negative results will be produced * If a test is 90% sensitive then 10% of people tested could be false-negative or found normal.
75
Positive controls
contain a small concentration of the component we are interested in detecting. If the method is sensitive and a positive control is tested, our test result should be positive.
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Error
is inexactness in measurement; for example, estimating the money in your wallet as $100 when it truly is $85.04. In the lab we are concerned with analytical errors, which are errors that occur during the analysis of a sample. Analytical errors are divided into systematic and random.
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Analytic period: Systematic errors This is a change in what
are associated with a change in accuracy. Systematic errors affect all theresults of a method in either a positive or negative fashion. Such errors will be of the same magnitude and in the same direction and are generally predictable, identifiable and correctable. For example a technologist might introduce a systematic error into a spectrophotometric method by erroneously setting zero absorbance using the first standard instead of distilled water. This will cause all consequent absorbance readings to be off by the amount of absorbance of the first standard
78
common causes of systematic errors
* stray light * scratches on cuvettes * improper sample storage * inaccurate standard graphs * outdated reagents * instruments which have an incorrect zero Absorbance
79
Random errors Change in what
are associated with a change in precision. Random errors are more difficult to monitor in the lab because they happen without prediction or regularity. Random errors can be due to carelessness and inattention
80
Common causes of random error in the clinical laboratory are:
* transcription errors * inaccurate patient identification * inaccurate patient or sample preparation * dirty glassware variation
81
Variation
is change or deviation in results that can have a significant effect on the precision and accuracy of lab results. The lab attempts to control variation by evaluating methods through statistical means.
82
Variations in sample analysis that labs must regularly deal with include:
* physiological variations such as age, sex and diet * differences in technique of specimen collection * differences in technique by those performing the test method
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Qualitative variables
are observable characteristics such as urine colour and clarity.
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Quantitative variables
refer to numerical observations such as length of time of a method, the concentration of an analyte in a sample or the size of an object
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Variables are classified into two types: discrete and continuous 1) Discrete variables
are those observations which can be counted. For example, the number of pennies saved in a day or the number of test tubes a lab uses in a month.
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2) Continuous variables
are those for which any value within a particular range is possible. For example, a 19 year old individual is somewhere between 19 years, 1 day old and 20 years. A 5 mL volumetric pipette may measure somewhere between 4.99 and 5.03 mL.
87
A population is a
large body of data which does not have to be finite. It is impossible to measure each member of a population; therefore we evaluate a sample to make inferences about the population. The sample is any part of the population and should be a random representative of the population. In this way, every member of the population has an equal opportunity of being chosen
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T/F When we receive a new lot # QC it is analyzed for several days (usually along side the current lot#) to determine the control range (>20 samples/20 days of each Low, Normal, or High controls)
T
89
Measurement of Variability affected by
-operator technique -environmental conditions -performance characteristics of the measurement
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3 Measures of Central Tendency
Mode, median, mean
91
mode
the value which occurs with the greatest frequency
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median
the value at the center or midpoint of the observations
93
mean
the calculated average of the values -The mean is the lab’s best estimate of the analyte’s true value for a specific level of control
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Normal Distribution
* When data have a normal spread or distribution, the median, mean and mode are similar or identical values * All values symmetrically distributed around the mean * Characteristic “bell-shaped” curve * Assumed for all quality control statistics To determine level of precision the lab is performing at…the dispersion of the data about the mean is considered
95
Standard Deviation (S) or SD Principle measurement of
* SD is the principle measure of variability used in the laboratory * It is a statistic that quantifies how close numerical values (QC values) are in relation to each other. * Precision is often used interchangeably with standard deviation * Used to monitor on-going day-to-day performance * = the standard (or typical) amount that scores deviate from the mean
96
Consistent SD
low standard deviation, low imprecision
97
Inconsistent SD
high standard deviation, high imprecision
98
CV formula
SD/ mean x 100= x.x% the lower the better
99
ACCEPTABLE CV for Manual methods is
less than or equal to 10%
100
ACCEPTABLE CV for Instrument methods
3.0% or less
101
CV The better the x the x cv
* The better the precision the lower the CV * CV is the great statistical equalizer * Measure of relative variability
102
4 Frequency Distribution Curves
* Data table * Frequency table * Bar graph* * Histogram*
103
Gaussian or Normal Distribution
It is the key to the statistical quality control * The mean, median and mode are identical * Used to verify the on-going performance of analytical systems + 1 SD 68% of the time + 2 SD 95% of the time + 3 SD 99.7% of the time
104
How can we relate Gaussian to Standard Deviation and Probability?
* We can predict that the data will fall within a specific percentages of the mean on the Gaussian curve * 95% of the results/data points will fall within + 2SD
105
T/F random errors = SD increase= shit in precision
T
106
T/F systemic errors lead to mean change = shift in accuracy
T
107
What is a reference range?
= range of results for clinically 95% of healthy people * If they fall outside this reference range this indicates a possible disorder/clinical issue * It is the range that a patient’s results should typically fall within if they are healthy
108
Control range
= the acceptable range of a known control sample for an analyte in order to monitor the precision and accuracy of our analytical system
109
* A reference range is dependent on the population being tested * And also dependent on the individual being tested * What does this mean?
There are physiological variables, laboratory variables, and/or patient indicators
110
For most lab tests we do not just give out reference intervals unless they are in a patient result chart why?
Variance between laboratories
111
When to re-evaluate Reference ranges?
* Method is modified, removed or added * Method becomes automated * Population changes significantly * Method changes entirely
112
Calibrators/Standards
* Multiple calibrators/diluted standards in increasing concentrations are measured and results are plotted on a graph/curve which is used to extrapolate or calculate the concentration of analytes in QC and patients * Automated analyzers store the calibration data * Frequency of calibrations depends on the analyzer and the methodology (set by manufacturer)
113
Common Reasons why calibration fails?
* Improper mixing of calibrator * Improper constitution of calibrator * Improper mixing in instrument * Instrument sample delivery issue * Change in calibrator lot # * Contaminated reagent/calibrator * Expired reagent/calibrator * Impure water system
114
When to Calibrate
* New lot # reagent loaded on analyzer * When required as per manufacturer (intervals) * When troubleshooting (QC is out) * After maintenance procedures * QC is ALWAYS run after calibration
115
Quality Control Testing * The ISO calls this process, ‘Ensuring the Quality of Examinations
This is achieved by employing error detection mechanisms to safeguard the examination or analytical phase
116
Criteria for Control material
1. Patient-like material (human serum, urine, or spinal fluid) 2. Have a known quantity of analyte present to cover spectrum of possible results test menu (low, normal, high) 3. Must be stable for extended time 4. Material should be reproducible * Vial to vial homogenous * Reconstitution must be the same 5. Easy to use 6. Contain all constituents you need to measure * Ex. Every test you will run on a patient must be present in the control samples
117
Commercial Controls
* Purchased as kits or boxes with several vials of lypophilized material * Each box has a lot# * A specific amount of diluent added to each vial to reconstitute * Material resembles human material * All pre-tested for presence of Hepatitis and HIV
118
Blind Duplicate Patient samples as controls
* A patient sample may serve as a control * Usually qualitative analysis
119
liquid stable vs lyophilized IQCs
ready to use vs need additions bcs they are free dries
120
advantages vs disadvantages of commercial controls Assayed vs nonassayed
assayed prior by manufacturer and unassayed not tested prior assayed: expensive, used to evaluated accuracy and precisions , avoids lab erroes unassayed: cheaper, precision only, avoids manufacturer errors
121
in house controls
uses pooled sera
122
covid electronic controls vs internal control
if the electronic control was working vs if the sample was enough
123
how many variables for control
at least 20-30
124
outlier
outside 3SD
125
Every QC system or lab should have at least 2 (preferably 3) levels of controls that are run daily (low, normal, high) * Why?
sick patients will have these diff levels
126
QC range is established now you have to monitor QC in the lab * QC chart used is called
Levey-Jennings or LJ chart 20-30 day period 1-3Sd and mean 1 control leverl on 1 chart
127
What happens if some data points fall outside the Gaussian pattern (3SD)? The Gaussian curve would widen...indicates what error
widen=random error
128
What if 68% of values are shifting to one side? Gaussian curve has shifted to one side of mean and indicates
shifted= systemic errors
129
T/F LJ is basically a Gaussian on its side separated by time as a frequency
T
130
LJ chart 3 must have rules in labs
1, every lab has a graph systme 2, daily control values are plotted vs time 3, lines are drawn to conncet
131
T/F * Precision and long-term accuracy are confirmed on a LJ chart by control values that remain clustered about the mean with little variation in the upward or downward direction
T
132
What to do after the results are plotted on LJ?
* The technologist needs to assess the quality of the run * The technologist should look for systematic error and random error * Long term inaccuracy is identified on LJ by either a trend or a shift * Trends and shifts are systematic errors
133
Systematic Error
A change in the mean of the control values * Change in the mean may be gradual and demonstrated as a trend in control values * Or it may be abrupt and demonstrated as a shift in control values
134
review shift vs trend causes image
135
There is unacceptable (unexpected)random error that is any data point outside the expected population of data
outside 3sd
136
shift
control on one side of the mean 6 consecutive days
137
trend
control moving in one direction heading toward an out of control value
138
Advantages of LJ
* Good visual representation of precision and accuracy * Easy to interpret
139
Disadvantages of LJ
* Time to maintain data * Must be plotted at the time of assay and in order * Acceptable conditions must be met or prevent release of patient results * Westgard rules provide some practical solutions to the disadvantages of LJ
140
There are usually more than one test/analyte tested in each bottle of QC… what if you run all the tests that are on your analyzer on level 1 and level 2 QC….and all the tests are “in control” and acceptable except the glucose????
report only if the test is not gluose related this indicates there is something with the reagnet, the QC bottles are fine