Concepts of Quality Control and Safety in Serologic Testing Flashcards
Referes to the overall process of guaranteeing quality patient care
Quality Assessment or Quality Assurance
Variables that occur before the actual testing of the specimen
Pre-analytical factors
Processes that directly affect the testing of specimens
Analytical factors
Processes that affect the reporting of results and correct interpretation of data
Post- analytical factors
Test request
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factor
A
Patient preparation
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factor
A
Specimen collection, handling and storage
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factor
A
Reagents
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factors
B
Instrumentation and equipment: instrument calibration and maintenance
B
Testing procedure
A. Pre analytical factor
B. Analytical factor
C. Post analytical factor
B
Preventive maintenance
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factor
B
Access to procedure manuals
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factor
B
Competency of personnel performing the test
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factor
B
Communication of test result
a. Pre-analytical factor
b. Analytical factor
c. Post- analytical factor
C
Refers to materials, procedures and techniques that monitor the accuracy, precision and reliability of a lab test
Quality control
It is performed to ensure that acceptable standards are met during the process of patient testing
Quality control
It is used to verify the accuracy and precision of a test and are exposed to the same conditions as the patient samples
External quality control
It is the ability to obtain the expected result
Accuracy
It is the ability to obtain the same result on the same specimen
Precision
It is the ability to maintain both precision and accuracy
Reliability
It consists of internal monitoring systems built into the test system
Internal quality control
It monitor the correct addition of a patient specimen or reagent, the instruments/reagents interaction and test completion
Internal or procedural controls
It monitor a test system’s electronic or electric components
Electric control
It is the testing of unknown sample received from an outside agency
Proficiency testing
It provides unbiased validation of the qualify of patient test result
Proficiency testing
Term: How close the measurement is to the value
Accuracy
Term: how close the results are when the same sample is tested multiple times
Precision
Term: range of values over which Laboratory can verify accuracy of a test system
Reportable range
Term: formerly called a normal value
Reference interval
Lowest concentration of a substance that can be detected by a test method
Analytical sensitivity
Ability of method to measure the only analyze it is supposed to measure and not the other related substances
Analytical specificity
Process of testing and adjusting analyzer’s readout to establish a correlation between measured and actual concentrations
Calibration
Reference material with a known concentration of analyte
Calibrator
Testing materials of known concentrations (calibrators, controls, proficiency testing samples, patient specimens with known values) to ensure the accuracy of results throughout reportable range
Calibration verification
The three levels that calibration verification test:
High, mid point, and low
Calibration verification requires how many months when a lot number of reagents changes, following preventive maintenance of repair and when controls are out of range
6 months
When is a calibration verification required?
1 when a lot number of reagents changes
2 to follow preventive maintenance or repair
3 when controls are out of range
Positive result in a patient who has the disease
True positive (TP)
Positive result in a patient who does not have the disease
False positive (fp)
Negative result in a patient who does not have the disease
True negative (TN)
Negative result in a patient who has the disease
False negative (fn)
% Of the population with the disease that tests positive
Diagnostic sensitivity
% Of population without the disease that test negative
Diagnostic specificity
% Of the time that a positive result is correct
Positive predictive value ((PPV))
% Of the time that a negative result is correct
Negative predictive value ((npv))
Study to verify the accuracy of a new method
Correlation study
Schedule of maintenance to keep equipment in peak operating condition
Preventive maintenance
Procedures specified by the manufacturer to evaluate critical operating characteristics of a test system
Function checks
Comparison of patient data with previous results
Delta check
