Quality Control Flashcards
Assessment of control values used to evaluate Quality Assurance
Mean
SD
A system in recognizing and MINIMIZING ANALYTICAL ERRORS.
Quality Control
This is done EVERYDAY and is FIRST to perform before patients samples are tested, processed and released.
Quality Control
Purpose of Quality Control
Monitor Analytical Processes (to ensure accuracy and precision)
Detect Analytical Errors
Prevent incorrect reporting of results.
Objectives of Quality Control
Mnemonics:
SM
QR
TE
CHECK: Machine-Reagent-Errors
(S)tability of (M)achines
(Q)uality of (R)eagents
(T)echnical (E)rrors
Two (2) known samples in the Laboratory
Standard
Control
Two types of ANALYTICAL ERRORS
RandoM
SystematiC
It is the most common cause of error in the Laboratory
Patient Misidentification
Note: Clerical Error is also HIGHEST source of error in the Laboratory. Patient misidentification is a type of Clerical Error.
Turn around time (TAT) is incorporated in the ________, _________, ________.
Pre-analytical Phase
Analytical Phase
Post-analytical Phase
STAT
Greek: STATIM “immediately”
Processing of STAT specimens
Within 30 to 60 minutes
Random Error and Systematic Error are errors involved in ___________.
Analytical Errors
Rando(M) Errors
Error: ________
Cause: _________
Test: _______ *Mnemonics: SPF
Error: Indeterminate; Varies sample to sample; By chance; Individual differences
Cause: Imprecision
Test: SD, CV, F-test
Systemati(C) Errors
Error: ________
Cause: _________
Test: _______ *Mnemonics: MAT
Error: Determinate, Consistent in one direction; Constant differences
Cause: Inaccuracy:
Test: Mean, T-test
Causes of Random Errors
Mnemonics: I’M POTI DiVo
(I)nstrumentation sudden malfunction
(M)islabeling
(P)ipetting Error
(O)perator Error
(T)emperature fluctuation
(Di)rty Optics
(Vo)ltage problem
Causes of Systematic Errors
Mnemonics: DICC (F)rom (W)innie the (P)ooh
(D)etorriorating Reagent
(I)mproperly made standard reagent
(C)ontaminated soutions
(C)alibration problems
(From)ailing Instrumentation
(Winne)rong reagent blank
(Po)orly written procedures
Errors caused by handwritten labels, request forms, and results.
Clerical Error
Clerical errors are __________, and __________ errors.
Pre-analytical and Post-analytical
Variation
Errors that occurs in collection, preparation, and measurement of SAMPLES.
Variation are errors in _________, and _________.
Analytical and Post-analytical
___________ are specimens analyzed for QC purposes.
QC materials
A known analyte solution with ONE sample resembling human sample and MOST SPECIFIC analytical solution.
Standard Reagent
Universal Color of Standard
Colorless
A known analyte solution with MULTIPLE sample resembling human sample
Control Reagent
Universal Color of Controls
Yellow - Serum like
Number of Control Solutions:
General Chemistry, _____ levels of control solution
Immunoassays, _____ levels of control solution
General Chemistry - Two (2)
Immunoassays - Three (3)
Two Level of control solutions in General Chemistry
Normal Control
High Abnormal Control
ROUTINELY USED SOURCE of control solution that is a non-biohazard animal serum
Bovine-based Control
A specimen that should never be accepted (both as a control and sample) in the Laboratory
Hemolyzed Samples
Control solutions (pooled human sera) are and should be ____________, ___________, ___________.
Non-icteric
Non-hemolyzed
Non-infectious
What are the accepted and rejected specimens for control solutions and samples?
Accept control if; non-icteric, non-hemolyzed, Non-infectious.
Reject control if; icteric, hemolyzed, infectious
Accept sample if; icteric, non-hemolyzed, lipemic, infectious
Reject sample if; Hemolyzed
A type of QC that provide a DAILY MONITORING of accuracy and precision to detect systematic and random error EVERYDAY.
Intralab QC
Interlab QC provides a ________ accuracy of the analytical method and involve Proficiency Testing
Long Term
Method used to validate a particular measurement process. The results are compared with other external laboratories to give an objective indication of test accuracy for LABORATORY ACCREDITATION.
Proficiency Testing (Interlab QC)
Gold Standard for External Laboratory QC
NEQAS/EQAP
ISO 15189: 2007
Effort by CAP to improve PATIENT CARE through QUALITY LABORATORY PRACTICE
Number of samples that are sent yearly recommended by CAP for proficiency testing
Before: Annually or periodically (once a year); 12 samples
Current (2019): Bi-annually (twice a year); 6 samples
Measures the smallest amount of concentration of the analyte or a.k.a Detection of Limit (doT)
Analytical Sensitivity
Portion of individuals to detect the PRESENCE/WHO HAVE the disease.
Diagnostic Sensitivity
Measures the ONLY ONE analyte of interest
Analytical Specificity
Nearness of the values to the TRUE VALUE
Accuracy
Nearness of the values to EACH OTHER
Precision/Reproducibility
Accuracy and precision OVER TIME
Reliability
Degree which the method can be easily REPEATED/REPLICATED
Practicability
Portion of the individuals to detect the ABSENCE/WITHOUT the disease
Diagnostic Specificity
__________ are the expected values that are represented by intervals of acceptable values with
upper and lower limits.
Control Limits
Highly Sensitive Methods results to __________.
Highly Specific Methods results to ___________.
- False positive
- False negative
1SD:__________
2SD:__________
3SD:__________
1SD: Gold Standard
2SD: Ideal SD; warning
3SD: Reject; correct
Predictive Value Theory (March, 2019)
a.k.a Baye’s Theorem
States the relationship between pre-tests and post-tests
Tests for Imprecision
SD
Precision
F-test
Test for Inaccuracy
Mean
Accuracy
T-test
Most frequently used measure of VARIATION/IMPRECISION
SD
Acceptable CV
CV: 2-4%
___________ signifies CONSTANT SYSTEMATIC ERROR.
Y-intercept
Gussian Curve
a.k.a Norma Bell Shaped Curve
65-95-99 rule
Best: Establishing reference values
Mean and SD
Cumulative Sum Graph
a.k.a CuSum
Detect Change and early systematic (trend) error
Most common method: V-mask
Youden Plot
a.k.a Twin plot (2 - samples; laboratories)
Best: Interlab QC
Shewart Levey Jennings Chart
a.k.a Dot Plot
Most commonly used QC chart
Detect trend, shift, outliers and utilizes Westgard rules
EWMA
a.k.a Exponentially Weighted Moving Average Chart
Average for a specified number of previous results with newer results having more influence (weighted)
Number of QC charts for daily monitoring
12 charts
_____________ is a measure of the organization’s products or services against specific standards for COMPARISON and IMPROVEMENT.
Benchmarking (productivity and services)
Best Charts.
Internal QC: ___________
External QC: ___________
Internal QC: Levey Jennings Chart
External QC: Youden/Twin Plot
Warning Rule
1 2S
Should 1 2S be accepted?
Yes. Other rules are rejected.
1 3S needs ___________ measure.
Corrective. It is Rejected, then it will only be accepted if corrected.
The range or difference of +-2SD, that is > than 4SD
R 4S
__________ provides a culture, infrastructure, methodology and metric toward QUALITY IMPROVEMENT
Lean Six Sigma
Pioneer in the field of Quality Improvement (Lean Six Sigma)
Dr. J. M. Juran
Lean Six Sigma is the _______________ that distinguishes an organization.
Rate of Improvement
Six Sigma reduces _____________.
Laboratory Errors
Reporting of errors
Deficit per million opportunities (DPMO)
Lean System reduces _____________.
Laboratory waste
5S used in Lean System
5S:
Sort
Set in order
Shine
Standardize
Sustain
PDCA
Plan
Do
Check
Act
DMAIC
Define
Measure
Analyze
Improve
Control
Function of DMAIC five phase methodology
Ensure sound problem solving
Root cause analysis
Most common Lean Six Sigma Team Roles.
Blue: _______
Black: _______
Green: _______
Blue: Project Sponsors
Black: Project Leader
Green: Project team member
Non-laboratory personnel are responsible for ____% of the error
29%
