SOP for Quality Assurance programme in Clinical Biochemistry
Aim: To design a standard operating procedure for Quality assurance programme comprising both Internal and External Quality Control programs in Clinical Biochemistry.
Principle: A detailed procedure outlined for Internal and External Quality Assurance program can give better insight for understanding the sequential steps involved in the same as Clinical Chemistry deals with a battery of test parameters. It is essential to adhere to these steps as it directly affects the results of quality control samples. This SOP will cover the detailed procedure for IQC,EQAS and Lot validation.
Responsibility: Senior Technician, Supervisor, Consultant, Quality Manager
IQC:
Procurement-For IQAS Biochemistry BIORAD Assayed Chemistry Controls and for Immunoassay. Immunoassay plus controls are used. Stock for controls is procured for atleast 2-3 months from the vendor
Storage- The product is stable until the expiry date of the same, when stored unopened at 2-80C (Refrigerator temperature). After reconstitution the product is stable at -100C to – 200C for 30 days. Reconstitution- Following steps are involved in reconstitution of control
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Follow the manufacturer instructions
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Use a fixed volumetric pipette
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Each vial is reconstituted with deionized water
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Vial kept standing for 20 minutes
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Swirl the vial occasionally
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The controls are alliquoted in labeled sample vials (appendrops)
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Vials are kept in refrigerator for 15-20 minutes
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Vials are then transferred to freezer
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Frozen aliquots are kept at -200C
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Aliquots are thawed at room temperature and are ready for use
Nomenclature for aliquots of Controls:
The reconstituted controls are alliquoted and the vials are labeled as follows:
No | Name of Control | Level 1 | Level 2 | Level 3 | Quantity reconstituted | Quantity of each alliquot |
1. | BIO-RAD Chem controls | BR1 | BR2 | ------ | 5ml | 380ul |
2. | Immunoassay plus controls | IB1 | IB2 | IB3 | 5ml | 400ul |
3. | Performance verifier | PV1 | PV2 | ------ | 3ml | 350ul |
4. | Urine Protein Control | UP2 | UP3 | ------ | 10ml | 200ul |
5. | ISO Performance verifier | CKMB1 | CKMB2 | ------ | 3ml | 150ul |
6. | Precicontrol maternal | PCMC1 | PCMC2 | PCMC3 | 3ml | 300ul |
7. | Precicontrol Tumor marker | TM1 | TM2 | ------ | 3ml | 200ul |
8. | Precicontrol Troponin- T | TN1 | TN2 | ------ | 2ml | 200ul |
9. | Precicontrol Cardiac | BNP1 | BNP2 | ------ | 2ml | 200ul |
10. | Precicontrol Varia | PCV1 | PCV2 | ------ | 3ml | 300ul |
11. | Precicontrol PCT | PCT1 | PCT2 | ------ | 4ml | 200ul |
12. | Precicontrol Anti CCP | CCP1 | CCP2 | ------ | 2ml | 150ul |
13. | Randox Cardiac Control | HCY1 | HCY2 | HCY3 | 2ml | 150ul |
Procurement: Following EQAS Programs are enrolled in Clinical Biochemistry
BIO-RAD EQAS Clinical Chemistry Program.
Immunoassay Program.
Cardiac Program.
Hemoglobin Program.
The respective vendor supplies the complete cycle (set of 12 samples) of all EQAS Programs
Storage: All the samples are stored at 2-80C until the expiry date, in an unopened condition. After reconstitution the sample is stable for 5 days at 2-80C.
Reconstitution- The controls are reconstituted just before processing them. Following steps are involved in reconstitution of control
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Follow the manufacturer instructions
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Use a fixed volumetric pipette
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Each vial is reconstituted with deionized water
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Vial is mixed properly and then processed
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Left-over reconstituted sample is alliquoted & kept in fridge
Volume of controls:
BIO- RAD Clinical Chemistry Program- 5ml
BIO- RAD Immunoassay Program- 5ml
Cardiac Program- Ready to use 1.5 ml
Hemoglobin Program- 0.5ml
Submission and evaluation of EQAS Results:
↓ ← Electronically
Through EQAS online
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Use unique laboratory code number for submission of results online
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Evaluated results are checked on QCNet by sub-department consultant
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The printouts of reports are filed in the EQAS file in the department
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In case of outlier parameter root cause analysis is done as per the checklist for same
Lot validation:
For lot validation of new control lot, it is processed in parallel with old lot control approximately within 7-10 days to get minimum 20 data points. The file for new lot is created and the lab mean of 20 points with the previous lot SD is updated on the instrument. LJ chart is reviewed month wise and if required at random intervals.
QC Rules:
We follow the following Westgard rules for daily review of QC chart for all analytes. The rules are as follows.
1.One 2s is warning rule .
2.In case of violation of QC rules we check for the following variable parameters
1.Room temperature.
2.Reasons for delay in processing of controls.
3.Reconstitution error.
4.Expiry date of controls.
5.Any major maintenance of the equipment.
6.Reagent storage/expiry date/onboard stability.
If all of the above mentioned are within acceptable limits and still there is violation of QC rules then we can proceed for calibration.
Reference- Product Manuals