1. Introduction to Lab Quality

2. Introduction to Quality
"The totality of features and characteristics of a product or service that bear on its ability to satisfy stated or implied needs".
Simply, “ Fitness of purpose”

3. Negative consequences of laboratory error
Less quality = more errors
unnecessary treatment
treatment complications
delay in correct diagnosis
additional and unnecessary diagnostic testing.
So high quality minimizes lab errors

4. Quality control Quality control:
QC is examining “control” materials of known substances along with patient samples to monitor the accuracy and precision of the complete analytic process.
QC is required for accreditation purposes.
Quality control can be quantitative, qualitative or semi-quantitative depending of the type of test used.
Positive & negative controls
Goal: to ensures both precision and accuracy of patient sample results

5. Quality control Quality control can be : - quantitative - qualitative
- semi-quantitative
depending of the type of test used.

6. Quantitative examinations
Quantitative examinations measure the quantity of an analyte present in the sample.
The measurement produces a numeric value as an end-point, expressed in a particular unit of measurement.
For example, the result of a blood glucose test might be reported as 50 mg/dL.

7. Qualitative examinations
Qualitative examinations are those that measure the presence or absence of a substance, or evaluate cellular characteristics such as morphology.
The results are not expressed in numerical terms, but in qualitative terms such as “positive” or “negative”; “reactive” or “nonreactive”; “normal” or “abnormal”; and “growth” or “no growth”. Examples of qualitative examinations include microscopic examinations, serologic procedures for presence or absence of antigens and antibodies, and many microbiological procedures.

8. Semi-quantitative examinations
Semi-quantitative examinations are similar to qualitative examinations, in that the results are not expressed in quantitative terms. The difference is that results of these tests are expressed as an estimate of how much of the measured substance is present.
Results might be expressed in terms such as “trace amount”, “moderate amount”, or “1+, 2+, or 3+”. Examples are urine dipsticks, tablet tests for ketones and some serologic agglutination procedures.

9. Microbiology QC
Gram stain QC : positive (S.aureus) & negative (E.coil)

10. Microbiology QC Media QC: - S.aureus : Blood agar
- H.influenza : chocolate agar
- E.coli : Macconkey agar

11. Types of Quality

12. 3- Post-analysis
1-Pre-analysis QA 2-

13. QC vs QA
Definition
QA is a process orientated and focus on defect prevention.
QC is a test orientated and focus on defect identification.

14. Quality assurance vs Quality control* *

15. Calibration Definition:
- “calibration is the correcting of a measuring device, usually by adjusting it to match or conform to a dependably known and unvarying measure.”

16. Calibrator vs. Control Materials
It is important not to confuse calibrators and control materials.
Calibrators are solutions with a specified defined concentration that are used to set or calibrate an instrument, kit, or system before testing is begun.
Calibrators are often provided by the manufacturer of an instrument.
They should not be used as controls since they are used to set the instrument.
A calibrator is a material or device with known quantitative / qualitative characteristics (concentration, activity, intensity, reactivity) that is used to calibrate, graduate, or adjust a measurement procedure.
A control is used to monitor the status of an analysis to maintain its performance within desired limits.

17. Controls are usually available in "high", "normal" and "low" ranges.

18. Purpose of Calibrator & Control
Calibrator: to set or correct the instrument
- Should be as pure as possible
Control : to assure that the instrument works correctly.
- Should be much like the clinical specimen

19. Summary Quality: Fitness of purpose
Quantitative examinations : measure the quantity of an analyte present in the sample.
Qualitative examinations : measure the presence or absence of a substance
Semi-quantitative examinations: an estimation of how much of the measured substance is present.
QA vs. QC
Calibrator: to set or correct the instrument
Control : to assure that the instrument works correctly.