QC & QA Flashcards
Clinical Laboratory Improvement
Amendments of 1988
(CLIA ’88)
-established minimum threshold for all testing
-definition of a laboratory
-introduced routine QC (quality control)
-min QC requirements for all nonwaived tests
Types of Quality Assessment Errors
Active - Healthcare worker to patient
Latent - Organization or lab design
Active Errors
-Fail to identify Patient
-MIssing blood vessel during phlebotomy
- Errors with collection tubes
- Errors with transportation system (Pneumatic tube)
-Errors with data entry
-Errors with instrument or computer (Ignore flags)
Latent Errors
-Staffing problems (chronic shortage)
-Information technology (no interface)
- Equipment malfunction
-Work environment (design, multitasking)
- Policy & Procedures (relabeling mislabeled tubes)
-Teamwork factors (shift change)
-Management/organization (profits, ignore patient safety/incident reports)
Quality Assessment-Phases of Testing
Preanalytical
Analytical
Postanalytical
What phase do most Errors happen
Preanalytical and Postanalytical
Error-improving strategies
-Formal patient safety training
-Enhanced communication between patients and laboratory staff and providers directly caring for patients
-Quality improvement projects that involve patient outcomes data and feedback
QA Considerations
Supervision
Procedure manual
Specimen collection and handling
Result reporting
Reagents, calibration and standards
Controls
Instruments and equipment
Personnel
Physical faciliites
Laboratory Safety
Two Components of QA Program
Non-analytical factors
Analysis of quantitative data (QC)
Nonanalytical factors of QA
-Qualified personnel
-Established laboratory policies
-Laboratory procedure manual
-Test requisitioning
-Patient identification, specimen procurement, and labeling
-Specimen transportation and processing
-Preventive maintenance of equipment
Phases of Testing QA
-Quality Assessment Phases of testing
-Proficiency Testing (CLIA required)
What is QC?
Procedures to monitor the accuracy and precision of test performance over time
What QC Helps to monitor
-Test system failure
-Adverse environmental conditions
-Variance in operator performance
Primary Goals of a QC Program
-Establish, maintain accurate and precise methods
-Determine level of precision
-Maintain reproducibility based on precision
-Instrument stability and performance
-CLIA compliance
-Benchmarks for improvement
Quality Control specimens
-A material or solution with a known concentration of the analyte being measured
-Controls can also be time, temperature, speed etc
QC For tests of moderate complexity (CLIA)
-perform and document QC using 2 levels of control material each day
-follow manufacturer’s instructions for QC
QA Descriptors, Aspects of clinical quality.
Accuracy
Calibration
Control
Precision
Quality control
Reliability (accuracy and precision)
Standards
Variance
Tight cluster, on Target
HIGH PRECISION, High Accuracy
Spread all around
Low accuracy, low pecision
Tight cluster, off target
High precision, low accuracy
spread Near target center
High Accuracy, Low precision
Sensitivity
-The proportion of cases with a specific disease or condition that gives a positive test result
-sensitivity = among patients with disease, the probability of a positive test
-(true positive no false negatives)
Specificity
-The proportion of cases with absence of the specific disease or condition that gives a negative test result
- specificity = among patients without disease (i.e. healthy patients), the probability of a negative test
-(true negative no false positives)
Sensitivity %
(True Positives / True Positives + False Negatives) X 100
Specificity %
(True Negatives / False Positives + True Negatives) X 100
Avoidable False Results
-Inappropriate time
- obsolete test
-test with inherently poor Sensitivity and Specificity.
- rest lacks extensive clinical validation
-test used on population that is different from studied population.
-Population with very high or low prevalence
Consequences of false results
-Maybe none
- Cascade of invasive and expensive tests.
- Lengthened hospital stay
- Additional office visits
- Inappropriate therapy
- Psychological Trauma to false belief
