PRELIM LEC: QUALITY CONTROL AND QUALITY ASSURANCE IN HEMATOLOGY Flashcards
Is the broader concept, encompassing
preanalytical, analytical, and postanalytical
variables
QUALITY ASSURANCE
Coordinated effort to organize laboratory activities
QUALITY ASSURANCE
Control and monitor
QUALITY ASSURANCE
Provide best service to patient and doctor
QUALITY ASSURANCE
Evaluate and monitor the accuracy and
precision of test performance over time
QUALITY CONTROL
To detect errors
QUALITY CONTROL
Same matrix as px specimen
CONTROL
Predetermined assay value
CONTROL
To identify for any contamination
CONTROL
Essentially pure form
PRIMARY STANDARD
Calibrate instrument
PRIMARY STANDARD
Time-consuming
PRIMARY STANDARD
Certified reference material
PRIMARY STANDARD
Fixed and known composition
PRIMARY STANDARD
Analyte concentration ascertained by reference to a primary standard
SECONDARY STANDARD
Preserved human or surrogate cell
suspension
CALIBRATOR
Closeness of results obtained from repeated analysis of same specimen
PRECISION
Closeness to the true or actual value
ACCURACY
Reproducibility
PRECISION
Assess change
DELTA CHECKS
Compare results from spx analysis with result of previous spx
DELTA CHECKS
Same analyte, same patient
DELTA CHECKS
Extent to which a method is able to maintain
accuracy and precision over time
RELIABILITY
Reference range
REFERENCE INTERVAL
Range of values of analyte in health individuals
REFERENCE INTERVAL
Proportion of px with the disease with positive result
DIAGNOSTIC SENSITIVITY
Proportion of px identified correctly by the
test as not having the disease
DIAGNOSTIC SPECIFICITY
TYPES OF ANALYTICAL ERRORS
- SYSTEMATIC ERRORS
- RANDOM ERRORS
Errors within test system or method
SYSTEMATIC ERRORS
Occur without prediction or
regularity
RANDOM ERRORS
SOURCES OF ANALYTICAL ERRORS
- Pre-analytical errors
- Post-analytical errors
INTERNAL QUALITY CONTROL
- Control sample
- Calibrators and Standards
Pre-analytical errors
Wrong tubes, wrong px
identification, wrong labeling,
improper transportation
Specially prepared specimen
treated as a px specimen
Control sample
o Adjust instrumentation
o Define a standard curve from which
patient’s result are read
Calibrators and Standards
Provide proficiency surveys
EXTERNAL QUALITY CONTROL
Monitor accuracy of individual laboratories
EXTERNAL QUALITY CONTROL
