How to Choose and Handle Quality Control Materials for Clinical Assays
By Dr. Zubair Khalid, DVM, MS, PhD ·
Quick Answer
- Select control materials that match the patient sample matrix and analyte concentration range relevant to your assay's clinical decision points.
- Verify commutability of control materials with your specific assay platform before routine use, as noncommutable controls can produce misleading QC results.
- Follow manufacturer instructions for storage, reconstitution, and handling, and document any deviation that could affect control performance.
Understanding Quality Control Materials in Clinical Diagnostics
Quality control materials are essential components of clinical laboratory operations. These materials contain known concentrations of analytes and are tested alongside patient samples to verify that an assay system performs within acceptable parameters. The fundamental purpose of QC materials is to detect analytical errors before they affect patient results. Without reliable control materials, laboratory professionals cannot distinguish between a properly functioning assay and one that has drifted out of acceptable performance.
The selection and handling of QC materials directly influence the validity of the quality control program. A control material that does not behave like a patient sample, or that has been improperly stored or reconstituted, will produce misleading results. These misleading results can lead laboratory professionals to reject valid patient data or accept invalid data. Both outcomes carry clinical consequences.
Laboratory professionals must understand the composition of control materials, the differences between available formats, and the specific handling requirements for each type. This understanding begins with the fundamental distinction between quality control materials and calibration materials. Calibrators establish the relationship between the measured signal and the analyte concentration. Quality control materials verify that this relationship remains stable over time. Using a calibrator as a control material, or vice versa, creates a circular validation that cannot detect systematic errors.
Types of Quality Control Materials
Lyophilized Control Materials
Lyophilized controls are the most common format in clinical laboratories. These materials are prepared in liquid form, dispensed into vials, and then freeze-dried to remove water. The freeze-drying process preserves the analyte in a stable state that can be stored at room temperature or refrigerated temperatures for extended periods.
The primary advantage of lyophilized controls is their long shelf life. Laboratories can maintain a consistent supply of the same lot for months or years, which supports long-term monitoring of assay performance. The primary disadvantage is the requirement for reconstitution. Each vial must be reconstituted with a precise volume of diluent, and the reconstitution process introduces a potential source of error.
Reconstitution errors are among the most common problems with lyophilized controls. If the laboratory professional adds the wrong volume of diluent, the concentration of the control will be incorrect. If the diluent is added too quickly or the vial is not swirled gently, the lyophilized material may not dissolve completely. Incomplete dissolution produces a control that is not homogeneous, and the measured concentration will vary between aliquots.
The reconstitution process requires careful attention to the manufacturer instructions. The diluent must be at the specified temperature. The vial must be allowed to stand for the specified time. The mixing must be performed with the specified technique. Deviations from these instructions can produce unreliable results.
Liquid Control Materials
Liquid controls are supplied in a ready-to-use format. These materials are stable in liquid form and do not require reconstitution. The primary advantage of liquid controls is the elimination of the reconstitution step, which removes a significant source of operator error.
Liquid controls are typically more expensive than lyophilized controls because the liquid matrix requires more sophisticated stabilization. The liquid format also has a shorter shelf life than the lyophilized format. Laboratories must monitor the expiration dates of liquid controls carefully and use them within the specified period.
The stability of liquid controls depends on the storage conditions. Most liquid controls require refrigeration at a specific temperature range. Some liquid controls are stable at room temperature for a limited period. The manufacturer's instructions must be followed precisely to maintain the integrity of the control material.
Human-Based Control Materials
Human-based controls are prepared from human serum, plasma, or other biological matrices. These controls are the most representative of patient samples because they contain the same matrix components. The matrix of a control material can affect the assay performance, and a control that uses a human matrix is more likely to behave like a patient sample.
The preparation of human-based controls requires careful screening of the source material. The source material must be tested for infectious agents and must be handled according to the biosafety principles described in the Biosafety in Microbiological and Biomedical Laboratories guidelines. The CDC and NIH provide the framework for the safe handling of human-derived materials in the laboratory.
Human-based controls may be pooled from multiple donors to achieve the desired concentration of the analyte. The pooling process must be performed under controlled conditions to ensure the homogeneity of the final product. The pooled material must be tested to verify the concentration of each analyte and to confirm the absence of interfering substances.
Animal-Based Control Materials
Animal-based controls use serum or plasma from animal sources. These materials are used when human-based controls are not available or when the assay requires a matrix that is not present in human-based controls. Animal-based controls are also used in veterinary diagnostics, where the patient samples are from animals.
The primary limitation of animal-based controls is the matrix difference. The animal matrix may contain proteins or other substances that interfere with the assay. The commutability of the animal-based control must be verified before the control is used for routine monitoring.
Synthetic and Matrix-Based Control Materials
Synthetic controls are prepared from purified components that are combined to create a material with the desired concentration of each analyte. These controls are used when the analyte is not available in a natural matrix or when the natural matrix is not stable.
Matrix-based controls are prepared by adding the analyte to a base matrix that is similar to the patient sample matrix. The base matrix may be a human serum pool, a bovine serum pool, or a synthetic matrix. The addition of the analyte must be performed under controlled conditions to ensure the homogeneity of the final product.
The selection of the base matrix is a critical decision. The matrix must be free of the analyte or must have a known concentration of the analyte that can be accounted for in the final concentration. The matrix must also be compatible with the assay method.
Criteria for Selecting Quality Control Materials
Matrix Compatibility
The matrix of the control material must be compatible with the assay method. The matrix is the composition of the material that contains the analyte. For most clinical assays, the matrix is serum or plasma. The control material should use the same matrix as the patient samples that are being tested.
A control material with a different matrix can produce results that are not comparable to patient samples. This difference is called a matrix effect. The matrix effect can cause the control to read higher or lower than the true concentration of the analyte. The matrix effect is a particular concern for immunoassays and other methods that rely on the interaction of the analyte with antibodies or other binding proteins.
The matrix compatibility must be verified for each assay method. A control that is compatible with one assay method may not be compatible with another method. The laboratory must verify the compatibility of the control with the specific assay method that is used in the laboratory.
Analyte Concentration
The concentration of the analyte in the control material must be appropriate for the assay. The control material should have a concentration that is within the analytical measurement range of the assay. The control material should also have a concentration that is near the clinical decision point for the analyte.
The clinical decision point is the concentration at which a clinical decision is made. For example, the clinical decision point for glucose is the concentration that distinguishes normal from diabetic. The control material should have a concentration near this decision point to verify that the assay is performing correctly at the concentration that matters for patient care.
The control material should also have a concentration that is within the linear range of the assay. The linear range is the range of concentrations over which the assay response is proportional to the concentration. If the control concentration is outside the linear range, the assay may not be able to measure the concentration accurately.
Commutability
Commutability is the property of a control material that describes how well the control material behaves like a patient sample. A commutable control material produces the same result as a patient sample with the same concentration of the analyte. A noncommutable control material produces a different result.
The commutability of a control material is determined by the manufacturer and is verified by the laboratory. The commutability of a control material can be affected by the matrix, the preparation process, and the presence of interfering substances. The commutability of a control material must be verified for each assay method.
The commutability of a control material is a critical factor in the selection of the control. A noncommutable control can produce results that are not representative of the patient samples. The laboratory must use a commutable control material to ensure that the QC results are reliable.
Stability and Shelf Life
The stability of the control material is a critical factor in the selection of the control. The control material must be stable for the period of use. The stability of the control material is determined by the manufacturer and is specified in the product insert.
The stability of the control material is affected by the storage conditions. The control material must be stored at the specified temperature and must be protected from light and moisture. The control material must be used before the expiration date.
The stability of the control material is also affected by the handling of the material. The control material must be handled according to the manufacturer's instructions. The control material must be reconstituted according to the instructions and must be used within the specified period after reconstitution.
Lot-to-Lot Consistency
The lot-to-lot consistency of the control material is the degree to which different lots of the control material produce the same results. The lot-to-lot consistency is determined by the manufacturer and is specified in the product insert.
The lot-to-lot consistency is important for the long-term monitoring of the assay. The laboratory must be able to compare the results of the QC from one lot to the next. If the lots are not consistent, the laboratory may not be able to determine whether a change in the QC results is due to the assay or due to the change in the control material.
The laboratory should use the same lot of the control material for as long as possible. The laboratory should also verify the lot-to-lot consistency when a new lot of the control material is introduced.
Handling and Storage of Quality Control Materials
Receiving and Inspection
The receiving and inspection of the control material is the first step in the handling of the material. The laboratory must verify that the control material is received in good condition. The laboratory must verify that the control material is the correct material and the correct lot.
The laboratory must verify that the control material has been shipped under the correct conditions. The control material must be shipped at the specified temperature. The control material must be shipped in a container that protects the material from damage.
The laboratory must verify that the control material has not expired. The laboratory must verify that the control material has not been damaged during shipping. The laboratory must document the receipt of the control material.
Storage Conditions
The storage conditions of the control material are specified by the manufacturer. The control material must be stored at the specified temperature. The control material must be stored in a location that is protected from light and moisture.
The storage temperature of the control material is critical for the stability of the material. The control material must be stored at the specified temperature. The control material must not be stored at a temperature that is outside the specified range.
The storage conditions of the control material must be monitored. The laboratory must monitor the temperature of the storage area. The laboratory must document the temperature of the storage area.
Reconstitution and Handling
The reconstitution of the control material is a critical step in the handling of the material. The reconstitution must be performed according to the manufacturer's instructions. The reconstitution must be performed with the correct volume of diluent.
The reconstitution must be performed with the correct technique. The diluent must be added to the vial slowly. The vial must be swirled gently to mix the contents. The vial must not be shaken vigorously.
The reconstitution must be performed at the correct temperature. The diluent must be at the specified temperature. The vial must be allowed to stand for the specified period.
The reconstitution must be performed in a clean environment. The reconstitution must be performed in a way that prevents contamination of the control material.
Handling and the Use of the Control Material
The control material must be handled in a way that prevents contamination. The control material must be handled with clean pipettes and clean containers. The control material must be handled in a way that prevents the introduction of the contaminants.
The control material must be used within the specified period. The control material must be used before the expiration date. The control material must be used before the specified period after the reconstitution.
The control material must be used in the same way as the patient samples. The control material must be tested in the same way as the patient samples. The control material must be tested in the same run as the patient samples.
Practical Implementation of the QC Material Selection
Step 1: Define the Assay Requirements
The first step in the selection of the QC material is to define the requirements of the assay. The laboratory must determine the analyte that is being measured. The laboratory must determine the matrix of the patient samples. The laboratory must determine the clinical decision point for the analyte.
The laboratory must determine the analytical measurement range of the assay. The laboratory must determine the linear range of the assay. The laboratory must determine the limit of detection and the limit of quantification of the assay.
The laboratory must determine the method of the assay. The laboratory must determine the type of the assay. The laboratory must determine the manufacturer of the assay.
Step 2: Review the Manufacturer's Instructions
The second step in the selection of the QC material is to review the manufacturer's instructions. The laboratory must review the product insert of the control material. The laboratory must review the product insert of the assay.
The laboratory must review the instructions for the storage of the control material. The laboratory must review the instructions for the reconstitution of the control material. The laboratory must review the instructions for the handling of the control material.
The laboratory must review the instructions for the use of the control material. The laboratory must review the instructions for the interpretation of the results of the control material.
Step 3: Evaluate the Control Material
The third step in the selection of the QC material is to evaluate the control material. The laboratory must evaluate the matrix of the control material. The laboratory must evaluate the concentration of the analyte in the control material.
The laboratory must evaluate the commutability of the control material. The laboratory must evaluate the stability of the control material. The laboratory must evaluate the shelf life of the control material.
The laboratory must evaluate the lot-to-lot consistency of the control material. The laboratory must evaluate the cost of the control material.
Step 4: Verify the Control Material
The fourth step in the selection of the QC material is to verify the control material. The laboratory must verify the control material before the routine use of the control material. The laboratory must verify the control material with the assay method.
The laboratory must verify the control material by testing the control material in the same way as the patient samples. The laboratory must verify the control material by testing the control material in the same run as the patient samples.
The laboratory must verify the control material by comparing the results of the control material with the expected results. The laboratory must verify the control material by comparing the results of the control material with the results of the previous control material.
Step 5: Document the Selection
The fifth step in the selection of the QC material is to document the selection. The laboratory must document the selection of the control material. The laboratory must document the lot of the control material. The laboratory must document the expiration date of the control material.
The laboratory must document the verification of the control material. The laboratory must document the results of the verification of the control material. The laboratory must document the date of the verification of the control material.
The laboratory must document the storage of the control material. The laboratory must document the handling of the control material. The laboratory must document the use of the control material.
Records and Measurements for QC Material Management
Documentation Requirements
The laboratory must maintain records of the QC material management. The records must include the lot of the control material. The records must include the expiration date of the control material. The records must include the date of the receipt of the control material.
The records must include the storage temperature of the control material. The records must include the date of the reconstitution of the control material. The records must include the results of the control material.
The records must include the verification of the control material. The records must include the results of the verification of the control material. The records must include the date of the verification of the control material.
The records must be maintained for the period specified by the laboratory. The records must be maintained in a way that allows the retrieval of the records.
Monitoring the QC Results
The laboratory must monitor the results of the QC material. The laboratory must monitor the results of the QC material on a regular basis. The laboratory must monitor the results of the QC material for the trends and the shifts.
The laboratory must monitor the results of the QC material for the trends. The trends are the gradual changes in the results of the QC material. The trends can indicate the drift of the assay.
The laboratory must monitor the results of the QC material for the shifts. The shifts are the sudden changes in the results of the QC material. The shifts can indicate the change in the assay.
The laboratory must monitor the results of the QC material for the outliers. The outliers are the results of the QC material that are outside the expected range. The outliers can indicate the error in the assay.
The Use of the Levey-Jennings Chart
The Levey-Jennings chart is a graphical tool for the monitoring of the QC results. The Levey-Jennings chart is a plot of the QC results over time. The Levey-Jennings chart is a plot of the QC results against the mean and the standard deviation of the QC results.
The Levey-Jennings chart is used to identify the trends and the shifts in the QC results. The Levey-Jennings chart is used to identify the outliers in the QC results. The Levey-Jennings chart is used to identify the systematic errors in the assay.
The Levey-Jennings chart is a useful tool for the monitoring of the QC results. The Levey-Jennings chart is a useful tool for the identification of the errors in the assay.
Common Failure Patterns in QC Material Handling
Improper Reconstitution
The improper reconstitution of the control material is a common failure pattern. The improper reconstitution can be caused by the addition of the wrong volume of the diluent. The improper reconstitution can be caused by the incomplete solution of the lyophilized material.
The improper reconstitution can be caused by the use of the wrong diluent. The improper reconstitution can be caused by the use of the diluent at the wrong temperature. The improper reconstitution can be caused by the use of the diluent that is contaminated.
The improper reconstitution can be caused by the use of the wrong mixing technique. The improper reconstitution can be caused by the use of the vigorous shaking. The improper reconstitution can be caused by the use of the vortex mixing.
The improper reconstitution can be detected by the observation of the control material. The improper reconstitution can be detected by the observation of the particulate matter in the control material. The improper reconstitution can be detected by the observation of the incomplete solution of the control material.
The Improper Storage
The improper storage of the control material is a common failure pattern. The improper storage can be caused by the storage of the control material at the wrong temperature. The improper storage can be caused by the storage of the control material at the temperature that is too high.
The improper storage can be caused by the storage of the control material at the temperature that is too low. The improper storage can be caused by the storage of the control material in the light. The improper storage can be caused by the storage of the control material in the moisture.
The improper storage can be detected by the observation of the QC results. The improper storage can be detected by the observation of the change in the QC results. The improper storage can be detected by the observation of the change in the appearance of the control material.
The Use of the Expired Control Material
The use of the expired control material is a common failure pattern. The expired control material is the control material that has passed the expiration date. The expired control material may not be stable.
The expired control material may not have the correct concentration of the analyte. The expired control material may not have the correct matrix. The expired control material may not be commutable.
The use of the expired control material can be detected by the observation of the QC results. The use of the expired control material can be detected by the observation of the change in the QC results. The use of the expired control material can be detected by the observation of the change in the appearance of the control material.
The Contamination of the Control Material
The contamination of the control material is a common failure pattern. The contamination can be caused by the use of the contaminated pipettes. The contamination can be caused by the use of the contaminated containers.
The contamination can be caused by the use of the contaminated diluent. The contamination can be caused by the use of the contaminated environment. The contamination can be caused by the use of the contaminated operator.
The contamination can be detected by the observation of the QC results. The contamination can be detected by the observation of the change in the QC results. The contamination can be detected by the observation of the change in the appearance of the control material.
The Limitations of the Quality Control Materials
The quality control materials have the limitations that must be considered. The quality control materials are not the same as the patient samples. The quality control materials may not be commutable with the patient samples.
The quality control materials may not have the same matrix as the patient samples. The quality control materials may not have the same concentration of the analyte as the patient samples. The quality control materials may not have the same stability as the patient samples.
The quality control materials may not be able to detect all the errors in the assay. The quality control materials may not be able to detect the errors that are not related to the concentration of the analyte. The quality control materials may not be able to detect the errors that are related to the matrix of the patient samples.
The quality control materials may not be able to detect the errors that are related to the interference of the patient samples. The quality control materials may not be able to detect the errors that are related to the contamination of the patient samples.
The limitations of the quality control materials must be considered in the interpretation of the QC results. The limitations of the quality control materials must be considered in the selection of the QC materials.
The Safety and Regulatory Context
The handling of the quality control materials must be performed in accordance with the biosafety requirements. The quality control materials may contain the infectious agents. The quality control materials may contain the human-derived materials.
The handling of the quality control materials must be performed in accordance with the Biosafety in Microbiological and Biomedical Laboratories. The CDC provides the standard for the safe handling of the biological materials. The NIH provides the guidelines for the recombinant and synthetic nucleic acid molecules.
The laboratory must perform the risk assessment for the handling of the quality control materials. The laboratory must identify the hazards of the quality control materials. The laboratory must identify the risks of the quality control materials.
The laboratory must implement the controls for the handling of the quality control materials. The laboratory must implement the engineering controls. The laboratory must implement the administrative controls. The laboratory must implement the personal protective equipment.
The laboratory must document the safety of the handling of the quality control materials. The laboratory must document the risk assessment of the quality control materials. The laboratory must document the controls of the quality control materials.
The Professional Escalation Criteria
The laboratory must escalate the issues with the quality control materials to the appropriate professional. The laboratory must escalate the issues with the quality control materials to the supervisor. The laboratory must escalate the issues with the quality control materials to the quality manager.
The laboratory must escalate the issues with the quality control materials when the QC results are outside the expected range. The laboratory must escalate the issues with the quality control materials when the QC results are trending. The laboratory must escalate the issues with the quality control materials when the QC results are shifting.
The laboratory must escalate the issues with the quality control materials when the control material is not commutable. The laboratory must escalate the issues with the quality control materials when the control material is not stable. The laboratory must escalate the issues with the quality control materials when the control material is not consistent.
The laboratory must escalate the issues with the quality control materials when the control material is contaminated. The laboratory must escalate the issues with the quality control materials when the control material is expired. The laboratory must escalate the issues with the quality control materials when the control material is not stored correctly.
The laboratory must escalate the issues with the quality control materials when the control material is not reconstituted correctly. The laboratory must escalate the issues with the quality control materials when the control material is not handled correctly. The laboratory must escalate the issues with the quality control materials when the control material is not used correctly.
The Comparison of the Control Material Types
| Control Type | Matrix | Preparation | Shelf Life | Primary Advantage | Primary Limitation |
|---|---|---|---|---|---|
| Lyophilized | Human or animal serum | Freeze-dried | Long | Extended stability | Reconstitution error |
| Liquid | Human or animal serum | Ready-to-use | Short | No reconstitution | Shorter shelf life |
| Human-based | Human serum or plasma | Pooled and processed | Variable | Matrix matches patient samples | Source screening required |
| Animal-based | Animal serum or plasma | Pooled and processed | Variable | Available when human is not | Matrix difference |
| Synthetic | Purified components | Combined | Variable | Defined composition | Matrix may not match |
The Selection Criteria for the Control Material
| Criterion | Consideration | Verification |
|---|---|---|
| Matrix | Must match the patient sample matrix | Verify with the assay method |
| Concentration | Must be within the clinical range | Verify with the assay method |
| Commutability | Must behave like the patient sample | Verify with the assay method |
| Stability | Must be stable for the storage period | Verify with the manufacturer |
| Shelf life | Must be used before the expiration date | Verify with the manufacturer |
| Lot-to-lot consistency | Must be consistent between the lots | Verify with the manufacturer |
The Common Failure Patterns and the Corrective Actions
| Failure Pattern | The Cause | The Corrective Action |
|---|---|---|
| The improper reconstitution | The wrong volume of the diluent | The use of the correct volume of the diluent |
| The improper reconstitution | The wrong mixing technique | The use of the correct mixing technique |
| The improper storage | The wrong temperature | The use of the correct temperature |
| The use of the expired control | The use of the expired material | The use of the unexpired material |
| The contamination of the control | The use of the contaminated pipettes | The use of the clean pipettes |
The Practical Workflow for the QC Material Selection
The practical workflow for the QC material selection is a step-by-step process. The workflow is a process that the laboratory can use to select the QC material.
The workflow is the following:
- Define the assay requirements.
- Review the manufacturer's instructions.
- Select the control material.
- Verify the control material.
- Document the selection.
The workflow is a useful tool for the selection of the QC material. The workflow is a useful tool for the documentation of the selection of the QC material.
The Common Failure Patterns in the QC Material Handling
The common failure patterns in the QC material handling are the patterns that are the most common. The common failure patterns are the patterns that are the most likely to occur.
The common failure patterns are the improper reconstitution. The common failure patterns are the improper storage. The common failure patterns are the use of the expired control material. The common failure patterns are the contamination of the control material.
The common failure patterns are the patterns that the laboratory must be aware of. The common failure patterns are the patterns that the laboratory must be able to detect. The common failure patterns are the patterns that the laboratory must be able to correct.
The Records and the Measurements
The records and the measurements are the documentation of the QC material management. The records and the measurements are the documentation of the selection of the QC material. The records and the measurements are the documentation of the handling of the QC material.
The records and the measurements are the documentation of the storage of the QC material. The records and the measurements are the documentation of the reconstitution of the QC material. The records and the measurements are the documentation of the use of the QC material.
The records and the measurements are the documentation of the verification of the QC material. The records and the measurements are the documentation of the results of the QC material. The records and the measurements are the documentation of the interpretation of the QC material.
The records and the measurements are the documentation that the laboratory must maintain. The records and the measurements are the documentation that the laboratory must use for the monitoring of the QC material.
The Quality Controls and the Welfare
The quality controls are the controls that the laboratory must use to ensure the quality of the assay. The quality controls are the controls that the laboratory must use to ensure the quality of the patient results.
The quality controls are the controls that the laboratory must use to ensure the quality of the QC material. The quality controls are the controls that the laboratory must use to ensure the quality of the QC material management.
The quality controls are the controls that the laboratory must use to ensure the quality of the QC material selection. The quality controls are the controls that the laboratory must use to ensure the quality of the QC material handling.
The quality controls are the controls that the laboratory must use to ensure the quality of the QC material storage. The quality controls are the controls that the laboratory must use to ensure the quality of the QC material reconstitution.
The quality controls are the controls that the laboratory must use to ensure the quality of the QC material use. The quality controls are the controls that the laboratory must use to ensure the quality of the QC material verification.
The Limitations of the QC Material
The limitations of the QC material are the limitations that the laboratory must consider. The limitations of the QC material are the limitations that the laboratory must consider in the interpretation of the QC results.
The limitations of the QC material are the limitations that the laboratory must consider in the selection of the QC material. The limitations of the QC material are the limitations that the laboratory must consider in the handling of the QC material.
The limitations of the QC material are the limitations that the laboratory must consider in the storage of the QC material. The limitations of the QC material are the limitations that the laboratory must consider in the reconstitution of the QC material.
The limitations of the QC material are the limitations that the laboratory must consider in the use of the QC material. The limitations of the QC material are the limitations that the laboratory must consider in the verification of the QC material.
The Safety and the Regulatory Context
The safety and the regulatory context of the QC material are the context that the laboratory must consider. The safety and the regulatory context of the QC material are the context that the laboratory must consider in the handling of the QC material.
The safety and the regulatory context of the QC material are the context that the laboratory must consider in the storage of the QC material. The safety and the regulatory context of the QC material are the context that the laboratory must consider in the reconstitution of the QC material.
The safety and the regulatory context of the QC material are the context that the laboratory must consider in the use of the QC material. The safety and the regulatory context of the QC material are the context that the laboratory must consider in the verification of the QC material.
The safety and the regulatory context of the QC material are the context that the laboratory must consider in the selection of the QC material. The safety and the regulatory context of the QC material are the context that the laboratory must consider in the documentation of the QC material.
The Professional Escalation Criteria
The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material. The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material to the professional.
The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material to the supervisor. The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material to the quality manager.
The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material when the QC results are outside the expected range. The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material when the QC results are outside the expected range.
The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material when the QC results are outside the expected range. The professional escalation criteria are the criteria that the laboratory must use to escalate the issues with the QC material when the QC results are outside the expected range.
The Relationship of the QC Material to the Assay
The relationship of the QC material to the assay is the relationship that the laboratory must consider. The relationship of the QC material to the assay is the relationship that the laboratory must consider in the selection of the QC material.
The relationship of the QC material to the assay is the relationship that the laboratory must consider in the verification of the QC material. The relationship of the QC material to the assay is the relationship that the laboratory must consider in the interpretation of the QC results.
The relationship of the QC material to the assay is the relationship that the laboratory must consider in the monitoring of the QC results. The relationship of the QC material to the assay is the relationship that the laboratory must consider in the troubleshooting of the QC results.
The relationship of the QC material to the assay is the relationship that the laboratory must consider in the documentation of the QC results. The relationship of the QC material to the assay is the relationship that the laboratory must consider in the reporting of the QC results.
The QC Material and the Assay Validation
The QC material is a component of the assay validation. The assay validation is the process of the verification of the assay. The assay validation is the process of the verification of the assay method.
The assay validation is the process of the verification of the assay performance. The assay validation is the process of the verification of the assay accuracy. The assay validation is the process of the verification of the assay precision.
The assay validation is the process of the verification of the assay sensitivity. The assay validation is the process of the verification of the assay specificity. The assay validation is the process of the verification of the assay linearity.
The QC material is a component of the assay validation. The QC material is a component of the assay validation that the laboratory must use to verify the assay. The QC material is a component of the assay validation that the laboratory must use to verify the assay performance.
The QC Material and the Diagnostic Assay Validation
The QC material is a component of the diagnostic assay validation. The diagnostic assay validation is the process of the verification of the diagnostic assay. The diagnostic assay validation is the process of the verification of the diagnostic assay method.
The diagnostic assay validation is the process of the verification of the diagnostic assay performance. The diagnostic assay validation is the process of the verification of the diagnostic assay accuracy. The diagnostic assay validation is the process of the verification of the diagnostic assay precision.
The diagnostic assay validation is the process of the verification of the diagnostic assay sensitivity. The diagnostic assay validation is the process of the verification of the diagnostic assay specificity. The diagnostic assay validation is the process of the verification of the diagnostic assay linearity.
The QC material is a component of the diagnostic assay validation. The QC material is a component of the diagnostic assay validation that the laboratory must use to verify the diagnostic assay. The QC material is a component of the diagnostic assay validation that the laboratory must use to verify the diagnostic assay performance.
The Analytical Sensitivity and the Specificity
The analytical sensitivity is the ability of the assay to detect the analyte. The analytical sensitivity is the ability of the assay to detect the analyte at the low concentration. The analytical sensitivity is the ability of the assay to detect the analyte at the low concentration of the analyte.
The analytical specificity is the ability of the assay to detect the analyte in the presence of the other substances. The analytical specificity is the ability of the assay to detect the analyte in the presence of the interfering substances. The analytical specificity is the ability of the assay to detect the analyte in the presence of the cross-reacting substances.
The analytical sensitivity and the specificity are the components of the assay performance. The analytical sensitivity and the specificity are the components of the assay performance that the laboratory must verify. The analytical sensitivity and the specificity are the components of the assay performance that the laboratory must verify with the QC material.
The analytical sensitivity and the specificity are the components of the assay performance that the laboratory must verify with the QC material. The analytical sensitivity and the specificity are the components of the assay performance that the laboratory must verify with the QC material.
The Laboratory Quality Control
The laboratory quality control is the process of the verification of the quality of the laboratory. The laboratory quality control is the process of the verification of the quality of the laboratory results. The laboratory quality control is the process of the verification of the quality of the laboratory results.
The laboratory quality control is the process of the verification of the quality of the laboratory results. The laboratory quality control is the process of the verification of the quality of the laboratory results. The laboratory quality control is the process of the verification of the quality of the laboratory results.
The laboratory quality control is the process of the verification of the quality of the laboratory results. The laboratory quality control is the process of the verification of the quality of the laboratory results. The laboratory quality control is the process of the verification of the quality of the laboratory results.
The laboratory quality control is the process of the verification of the quality of the laboratory results. The laboratory quality control is the process of the verification of the quality of the laboratory results. The laboratory quality control is the process of the verification of the quality of the laboratory results.
Frequently Asked Questions
What is the difference between a calibrator and a quality control material?
A calibrator is used to establish the relationship between the assay signal and the analyte concentration. A quality control material is used to verify that this relationship remains stable over time. Using a calibrator as a control material creates a circular dependency that cannot detect assay drift.
How do I choose between lyophilized and liquid control materials?
Lyophilized controls have a longer shelf life but require careful reconstitution. Liquid controls eliminate the reconstitution step but have a shorter shelf life. The choice depends on the assay volume, the storage capacity, and the risk tolerance of the laboratory.
What is commutability and why does it matter?
Commutability is the property of a control material that behaves like a patient sample in the assay. A noncommutable control can produce results that are not representative of patient samples. The commutability must be verified for each assay method.
How should I store lyophilized control materials?
Store lyophilized controls at the temperature specified by the manufacturer. Protect the controls from light and moisture. Monitor the storage temperature and document the temperature of the storage area.
What are the common errors in the reconstitution of lyophil
Related Diagnostic Guides
- Laboratory Quality Management System Certificate Program: What to Expect and How to Choose
- Microbiology Quality Control: Essential Practices for Reliable Culture Results
- Laboratory Quality Management System: A Guide to ISO 15189 Accreditation
- Method Validation in Clinical Laboratories: A Practical Protocol
References and Further Reading
- Molecular Biology and Laboratory Methods. National Library of Medicine.
- Biosafety in Microbiological and Biomedical Laboratories. CDC and NIH.
- NIH Guidelines for Recombinant or Synthetic Nucleic Acid Molecules. National Institutes of Health.
- Addgene Protocols. Addgene.
- MIQE Guidelines. Clinical Chemistry.
- NIST Laboratory Programs. National Institute of Standards and Technology.
- Laboratory Biosafety Manual. World Health Organization.
- NCBI Literature Resources. National Center for Biotechnology Information.
- Evolution of LC-MS/MS in clinical laboratories.. Clinica chimica acta, international journal of clinical chemistry, 2024.
- Problems associated with clinical chemistry quality control materials.. CRC critical reviews in clinical laboratory sciences, 1980.
- Quality control for the clinical laboratory.. Clinics in laboratory medicine, 1983.
This article is educational and does not replace validated laboratory procedures, institutional biosafety review, manufacturer instructions, or professional interpretation.