Introduction
All human clinical laboratory testing in the United States is regulated by the Clinical Laboratory Improvement Amendments of the US FDA,1 and other countries have similar regulations. Failure of such laboratories to correct issues of noncompliance with legislation results in lack of accreditation and termination of laboratory services. In contrast, veterinary laboratories are not uniformly regulated by government entities. Laboratory accreditation is offered by the American Association of Veterinary Laboratory Diagnosticians and is optional. This accreditation is “restricted to publicly funded, full-service laboratories, full service being defined as offering necropsy, histopathology, bacteriology, and virology or equivalent services on site.”2 The International Organization for Standardization offers certification for veterinary laboratories, but such certification is also voluntary in that it represents a commitment statement from the laboratory, without enforcement, with respect to adherence to the QA principles and procedures that are outlined in their standards for medical laboratories3 and general requirements for the competence of testing and calibration laboratories.4 Both the American Animal Hospital Association and the UK Royal College of Veterinary Surgeons have a laboratory quality section as a component of their overall veterinary hospital accreditation programs.
Just as measures for QA in the surgical suite (eg, autoclaving of instruments and sterile draping) are widely accepted standards of best practice, QA and continuous quality improvement are imperative in veterinary clinical diagnostic medicine. Lack of understanding of the magnitudes and causes of the statistical uncertainties that are inherent in all biological measurements can lead to misdiagnosis and poor patient outcomes. Preventive and corrective measures pertaining to statistical and nonstatistical QC in the laboratory are risk-management safeguards against the production of inaccurate data, which may carry ethical, financial, professional, and legal ramifications.
This is the first installment in a series of 5 articles intended to help veterinary practitioners and their staff provide quality management for in-clinic laboratory testing. Please watch for additional articles in the series in future issues of the JAVMA.
This is the first in a series of 5 articles intended to help veterinary practitioners and staff provide quality management for in-clinic laboratory testing. The purpose of these articles is to raise awareness of potential sources of laboratory error through evaluation of current practices and identification of potential areas of improvement. Another aim is to provide actionable QA goals and useful tools for their attainment, with the ultimate objective of maximizing the quality of laboratory output and thus diagnostic value to clients and patients. In this article, the concepts of the TQMS and the quality plan are introduced.
The TQMS
According to the brain-to-brain loop concept in human clinical diagnostic medicine, the generation of any laboratory test result consists of 10 steps, beginning with test ordering and ending with patient outcome (Table 1).5,6 The ends of the loop, which consist of the preanalytic and postanalytic phases of laboratory testing, have historically been less thoroughly evaluated and monitored than the analytic (instrument measurement) phase but are equally important. Research in human medicine has pinpointed errors during preanalytic phases as most common,7 and anyone who has interpreted a confusing laboratory report has encountered potential postanalytic error. Similar to this systems concept, it is useful to think of the veterinary diagnostic laboratory as operating within a framework of a formalized, planned TQMS, which operates as a systematic cycle or loop of components for continuous improvement (Figure 1).8,9 Design and implementation of such a system require a top-down commitment that engages all staff. Veterinary reference laboratories have highly trained staff who run daily QC testing on technologically advanced instruments, yet still regularly identify problems requiring correction. It follows that in-clinic laboratories would also have testing-related errors and, therefore, the need for quality improvement.
Stages and phases of laboratory testing according to the brain-to-brain loop concept in human clinical laboratory medicine.3,4
| Testing phase | Stage |
|---|---|
| Preanalytic | Test ordering |
| Sample collection | |
| Sample identification | |
| Sample transportation | |
| Sample preparation | |
| Analytic | Sample analysis |
| Postanalytic | Results reporting |
| Results interpretation | |
| Clinical decision-making | |
| Patient outcome |
Diagram of the components comprising the TQMS loop in clinical laboratory medicine. Reprinted with permission from Westgard QC. Lesson QP 2: assuring quality through total quality management. Available at: www.westgard.com/lesson50.htm.
Citation: Journal of the American Veterinary Medical Association 258, 1; 10.2460/javma.258.1.55
Planning for quality
The in-clinic laboratory should be organized as a separate cost center within the veterinary clinic, with its own budget, inventory control, and document control. A TQMS should begin with identifying personnel to serve as quality managers—ideally a veterinarian and technician who have an interest in laboratory testing and who are dedicated to motivating the staff to participate in a culture of in-clinic laboratory quality. Veterinary medical expertise is needed in the development of a TQMS to ensure that the intended uses of laboratory results (ie, diagnosis and treatment decisions) are integrated into the related plan and its implementation. These identified persons should develop a quality plan, which is first and foremost a statement of intent to provide high-quality laboratory testing that best serves the needs of patients and to provide a roadmap for how to get there. This plan should provide a framework for operation of the in-clinic laboratory as well as the clinic's philosophy and values that govern decision-making, which will support a commitment to continuous improvement. The level of detail should be sufficiently broad and high level so that the plan need not be changed whenever daily operational procedures are changed. The quality plan may reference more specific policies, procedures, records, and forms.
Once instituted, the quality plan should be reviewed periodically (every other year if no substantial infrastructure changes are made), updated as necessary, and easily accessible to all clinic personnel. The plan should be used for new personnel training and continuing education, and management may consider including among the clinic's client-facing informational and public relations materials a brief introduction or summary of the plan, notice of its existence, or general statement of the clinic's intent for organized laboratory quality planning (Appendix 1; Supplementary Appendix S1, available at: avmajournals.avma.org/doi/suppl/10.2460/javma.258.1.55). Major categories within the plan include the laboratory environment, personnel, equipment, and working practices.
Information regarding the laboratory environment should include the following:
Name and location of the clinic.
Statement on the values, vision, and mission of the laboratory.
Statement on the clinic's commitment to a TQMS with continuous quality improvement.
Description of clientele and patients.
General description of the types of laboratory services provided.
Description of dedicated laboratory facilities, such as where the laboratory is located within the clinic; whether there are different personnel shifts within a day; whether lockers, bathroom, and breakroom facilities are available for personnel; and whether access to reference materials and instruction manuals is provided.
Information regarding personnel should include the following:
Defined personnel laboratory roles and their respective training and ongoing competency requirements.
Health and safety practices, with a stated commitment to compliance with all federal and local requirements and training for prevention of zoonotic disease transmission.
Information about laboratory equipment should include the following:
Statement on commitment to appropriate selection and evaluation of instruments and analytical methods.
Statement on commitment to selection and design of routine QC procedures.
Statement on commitment to regular instrument and equipment maintenance.
Outline of required materials and their storage.
Finally, laboratory operations should be detailed regarding the following:
Commitment to conducting laboratory processes in accordance with written SOPs.
Reporting of results (eg, turnaround times for reporting to clients) and storage of data and patient samples.
Mechanisms of personnel and process evaluation.
Quality goals and standards
The core purpose of a TQMS is to support attainment of specified quality goals, which represent the laboratory accuracy requirements or standards that must be achieved to satisfy the needs of clinicians and that ensure patient safety (Figure 1). For the preanalytic and postanalytic phases, predefined goals are used to maximize sample stability and quality prior to analysis and to ensure accuracy in result reporting and interpretive support, respectively. For the analytic phase, the requirement is to provide test results that are correct (ie, represent the true result for the patient within stated limits of measurement error), can reliably provide information that differentiates health from disease, and can therefore inform appropriate clinical decision-making. A detailed discussion of statistical goal setting for analytic quality is beyond the scope of this article, and interested readers are advised to consult other resources.10,11,12,13 Examples of goals for preanalytic, analytic, and postanalytic phases of in-clinic laboratory testing may include (but are not limited to) the following:
All sample tubes, slides, and reports are labeled with a unique patient identifier (use of 2 identifiers is ideal because patients may have the same or similar names).
All samples have adequate substrate for testing (adequate volume for fluid phase samples).
All samples are visually inspected prior to analysis for any gross evidence of potential interfering properties (eg, hemolysis, lipemia, or icterus).
All samples are analyzed within a specified time limit as appropriate for sample stability.
If a QC failure is noted for an automated instrument, analysis of patient samples on that instrument ceases until the failure is remedied (note: the concept of statistical QC, including QC failure, will be discussed in the fifth article in this series).
Routine maintenance of instruments, microscopes, centrifuges, refractometers, and automated pipettes is performed in accordance with manufacturer instructions.
Any critical (potentially life-threatening) results are verified and immediately reported.
All results are relayed to clients within specified turnaround times.
All detected laboratory errors or indications for repeated testing due to error flags are documented and analyzed for root causes to guide appropriate corrective and preventive actions.
Quality laboratory processes and procedures
An SOP is a set of instructions that describes how to perform a laboratory procedure and ensures consistency and optimal quality for that procedure. Standard operating procedures describe the “how” of laboratory functions within the larger framework of the TQMS, which addresses both how and how well the work is being done. Each SOP should be of uniform format; an SOP template (ie, an SOP for how to write SOPs) should be developed and used to standardize the information presented. It should be detailed and clearly understandable, such that a staff member unaccustomed to the procedure would be able to perform it after reading the SOP. An SOP should be written for each and every laboratory function, including functions such as specimen accessioning and biological waste disposal. Importantly, SOPs do not solely pertain to the operation of more sophisticated instruments, such as those used for CBC and biochemical analyses. Veterinary personnel may want to consider the use of SOPs for all workflows, from the in-clinic laboratory to other clinic functions. Like the quality plan, SOPs are an integral and necessary component for providing adequate staff training, continuing education, and efficient, uniform laboratory operations. Because procedural changes are typically made more frequently than alterations of the more high-level topics in the quality plan, laboratory operating procedures and protocols should be kept in a distinct SOP manual. Creation of SOPs will be covered in more detail in the third article in this series.
QC and QA
The QC and QA components of a TQMS consist of monitoring daily laboratory work processes. Quality assurance is a generic term that refers to the monitoring and assessment of testing processes to allow identification and correction of problems to maintain performance. Although the terms can be used interchangeably, traditionally, QC refers to statistical and nonstatistical analyses performed during the analytic phase of testing, whereas QA refers to the broader monitoring of all dimensions and characteristics of quality, including during the pre- and postanalytic phases, instrument maintenance (including centrifuges, microscopes, and other nonautomated equipment), accurate record keeping (for instrument maintenance, QC assay results, reagent and calibrator logs, and patient reports), any external audits or accreditation requirements, and monitoring of turnaround time. Participation in an external quality assessment program or comparative testing with the clinic's reference laboratory for various types of instruments is recommended as part of ongoing quality assessment. This topic is outside the scope of this series of articles and is discussed in other resources.14,15,16,17
Quality control can be statistical or nonstatistical in nature. Statistical QC refers to the use of statistical methods to monitor and maintain the quality of products and services, whereas nonstatistical QC includes other checks and methods to ensure that accurate and reliable results are reported. Nonstatistical methods are used heavily in the pre- and postanalytic phases and also are an essential component for analytic tests with known limitations (eg, blood smear examination for leukocyte differential cell counts and evaluation of RBC morphology and any platelet clumping). Concordance of test results with clinical signs, results of other laboratory tests, and review of previous patient data are other examples of nonstatistical QC that may be used to evaluate test results. A useful concept for QA and QC is that of establishing KQIs (synonymous with key performance indicators or KPIs), which are selected to track current performance in key areas of laboratory function (Table 2). Measurement of KQIs will help to monitor successes and shortfalls in achieving the quality goals of the in-clinic laboratory and can highlight areas for improvement and future goal setting.
Examples of KQIs that may be used for monitoring and assessing QC and QA of in-clinic laboratories, organized by phase of laboratory testing.
| Preanalytic | Analytic | Postanalytic |
|---|---|---|
| No. (%) of laboratory samples insufficiently labeled with unique patient identifiers | No. (%) of test results indicating hypercalcemia* | No. (%) of laboratory results reported to clients beyond specified turnaround times† |
| No. (%) of blood or urine samples with an insufficient volume for testing | No. (%) of positive benchtop serologic test results for an infectious disease, compared with the known prevalence in the geographic area or any confirmatory test results | No. (%) of critical (life-threatening) values reported to the clinician on an immediate basis |
| No. (%) of EDTA- or heparin-treated blood samples for CBC with grossly visible clots | No. (%) of control-run failures (outside of specified acceptable control limits) | Mean time between sample collection and results reporting (particularly for critical values) |
| No. (%) of samples with visible hemolysis, lipemia, or icterus | No. (%) of tests with instrument alerts or error flags | No. (%) of corrected or amended reports |
| No. (%) of samples undergoing delayed analysis (beyond the recommendation for the specified test per stability of the sample) | No. (%) of blood smear preparations for CBC with measured thrombocytopenia, abnormal differential counts, and atypical scattergram plots (if available) | No. (%) of laboratory reports appropriately incorporated into patient medical records |
Analytic tests chosen for KQIs should have the lowest margin of error because the results are used for clinical treatment decisions, additional diagnostic investigations, and patient monitoring. If a QC problem has been identified for a particular measurand or measurands (ie, substances to be measured), such as instrument flags or data drifts in, for example, aggregate albumin data, these tests may be chosen to ensure that corrective and preventive actions have been effective.
Although typically classified as pertaining to the postanalytic phase, turnaround time is affected by all phases of the total testing process.
The term QA is occasionally used synonymously with quality assessment. Strictly speaking, quality assessment refers to a collection of monitoring systems as just described, whereas QA more correctly refers to the broad outcome of a TQMS and is not a component.
Quality improvement
Quality improvement is the final component of the TQMS feedback loop, whereby the information gained from QC and QA directly informs more planning (eg, modification of staff duties or training, SOPs, or quality plans) or specific actions in a cycle of continuous quality improvement. Problems, nonconformities, or failure to achieve desired laboratory quality goals can be identified in several ways, including the following:
Review of QC statistical data (instrument performance).
Implementation of improvement opportunity forms, which are simple forms placed at each laboratory workstation that enable staff to record issues and suggestions for better laboratory function.
Monitoring of KQIs.
Checking of consumable materials for any obvious defects, proper storage, expiry dates, proper disposal, and adequate stock supply.
Examination of groups of patient reports to identify possible trends or data shifts.
Review of staff and client feedback.
Management review of the TQMS and its components, including the laboratory budget and inventory control.
Monitoring and follow-up of any implemented preventive and corrective actions.
Monitoring and follow-up of any changes in the use of human or material resources.
Inherent to this list are recommended planned timelines for evaluation of the relative success of any implemented changes, evaluation of the TQMS itself by the quality manager or team, and periodic rereview of SOPs by staff (eg, after changes or every other year if no change has been made).
Clinical Bottom Line
Similar to other aspects of veterinary medicine, such as physical examination, surgery, diagnostic imaging, and medication protocols for specific diseases, the laboratory testing process should proceed in accordance with defined practices that can be tailored to the needs of the veterinary clinic and its patient base. From the veterinarian's decision to order a test, through to the patient's outcome following any diagnostic or treatment decisions made on the basis of that test, veterinary personnel have the responsibility to take necessary steps to help ensure that laboratory test results are reliable and acted upon appropriately to provide for the best possible patient care. A checklist is suggested as a launching point for implementation of the recommendations in this article (Appendix 2; Supplementary Appendix S2, available at: avmajournals.avma.org/doi/suppl/10.2460/javma.258.1.55). Board-certified veterinary clinical pathologists (eg, members of the American College of Veterinary Pathologists or European College of Veterinary Clinical Pathology), veterinary clinical laboratory directors, and laboratory professionals in industry, commercial diagnostic reference laboratories, and government-run diagnostic reference laboratories are available for further consultation on these matters; various other resources are also available.18,19,20 Additionally, voluntary laboratory accreditation options exist for veterinary clinics, typically as a component of a hospital accreditation program.21,22
Acknowledgments
No third-party funding or support was received in connection with this study or the writing or publication of the manuscript. The authors declare that there were no conflicts of interest.
Abbreviations
| KQI | Key quality indicator |
| QA | Quality assurance |
| QC | Quality control |
| SOP | Standard operating procedure |
| TQMS | Total quality management system |
References
- 1. ↑
US FDA. Clinical Laboratory Improvement Amendments (CLIA). Available at: www.fda.gov/medical-devices/ivd-regulatory-assistance/clinical-laboratory-improvement-amendments-clia. Accessed Jul 29, 2020.
- 2. ↑
American Association of Veterinary Laboratory Diagnosticians. AAVLD accreditation program. Available at: aavld.memberclicks.net/accreditation-explained. Accessed Aug 29, 2020.
- 3. ↑
International Organization for Standardization. ISO 15189:2012. Medical laboratories—requirements for quality and competence. Available at: www.iso.org/standard/56115.html. Accessed Aug 29, 2020.
- 4. ↑
International Organization for Standardization. ISO/IEC 17025:2017. General requirements for the competence of testing and calibration laboratories. Available at: www.iso.org/standard/66912.html. Accessed Aug 29, 2020.
- 5. ↑
Plebani M, Laposata M, Lundberg GD. The brain-to-brain loop concept for laboratory testing 40 years after its introduction. Am J Clin Pathol 2011;136:829–833.
- 6. ↑
Lundberg GD. Adding outcome as the 10th step in the brain-to-brain laboratory test loop. Am J Clin Pathol 2014;141:767–769.
- 7. ↑
Plebani M, Sciacovelli L, Aita A, et al. Performance criterial and quality indicators for the pre-analytical phase. Clin Chem Lab Med 2015;53:943–948.
- 8. ↑
Deming WE. Out of the crisis. Cambridge, Mass: Massachusetts Institute of Technology, Center for Advanced Engineering Study, 1986;1–17, 465–474.
- 10. ↑
Flatland B, Camus MS, Baral RM. Analytical quality goals—a review. Vet Clin Pathol 2018;47:527–538.
- 11. ↑
Nabity MB, Harr KE, Camus MS, et al. ASVCP guidelines: allowable total error hematology. Vet Clin Pathol 2018;47:9–21.
- 12. ↑
Harr KE, Flatland B, Nabity M, et al. ASVCP guidelines: allowable total error guidelines for biochemistry. Vet Clin Pathol 2013;42:424–436.
- 13. ↑
VetBiologicalVariation.org. Biologic variation in veterinary species. Available at: vetbiologicalvariation.org. Accessed Jul 29, 2020.
- 14. ↑
Camus MS, Flatland B, Freeman KP, et al. ASVCP guidelines: external quality assessment and comparative testing for reference and in-clinic laboratories. Vet Clin Pathol 2015;44:477–492.
- 15. ↑
Veterinary Laboratory Association. Quality assurance program. Available at: www.vetlabassoc.com/quality-assurance-program. Accessed Sep 11, 2020.
- 16. ↑
Synlab. Veterinary quality assurance scheme. Available at: vet.synlab.co.uk/the-veterinary-pathology-group-launches-their-external-quality-assurance-scheme. Accessed Sep 11, 2020.
- 17. ↑
Idexx. EQA programme for Idexx VetLab analysers. Available at: www.idexx.co.uk/en-gb/veterinary/reference-laboratories/eqa-programme. Accessed Sep 11, 2020.
- 18. ↑
Arnold JE, Camus MS, Freeman KP, et al. ASVCP guidelines: principles of quality assurance and standards for veterinary clinical pathology (version 3.0): developed by the American Society for Veterinary Clinical Pathology's (ASVCP) Quality Assurance and Laboratory Standards (QALS) Committee. Vet Clin Pathol 2019;48:542–618.
- 19. ↑
Centers for Medicare & Medicaid Services. Clinical laboratory improvement amendments. Available at: www.cms.gov/Regulations-and-Guidance/Legislation/CLIA/index. Accessed Jul 29, 2020.
- 20. ↑
CLSI. Global laboratory standards for a healthier world. Available at: http://clsi.org. Accessed Jul 29, 2020.
- 21. ↑
Royal College of Veterinary Surgeons. Apply for accreditation. Available at: www.rcvs.org.uk/setting-standards/practice-standards-scheme/apply-for-accreditation. Accessed Jul 29, 2020.
- 22. ↑
American Animal Hospital Association. AAHA standards of accreditation. Available at: www.aaha.org/accreditation-membership/aaha-standards. Accessed Jul 29, 2020.
Appendix 1
Hypothetical example of a quality plan for an in-clinic laboratory.
| Quality Plan for Laboratory Services |
|---|
|
Appendix 2
Checklist for development of a TQMS for in-clinic laboratories.
| Recommendation | Compliant? | Additional comments by auditor |
|---|---|---|
| At least 1 quality manager or team leader is identified who has a special interest in laboratory testing and who can educate and motivate the entire staff to participate in a culture of laboratory quality and continuous improvement. | □ Yes □ No | |
| A quality plan is drafted that includes descriptions of the laboratory environment, personnel, equipment, and working practices. | □ Yes □ No | |
| Quality goals are drafted for preanalytic, analytic, and postanalytic phases of testing. | □ Yes □ No | |
| SOPs are developed for all laboratory functions. | □ Yes □ No | |
| QC data are assessed for automated instruments per manufacturer instructions or more frequently. If QC failure occurs, the protocol is to cease patient sample analysis and troubleshoot until laboratory instruments are operating within QC specifications. | □ Yes □ No | |
| Laboratory spaces and equipment are clean and well maintained, with logs for recording cleaning and maintenance activities. | □ Yes □ No | |
| Reagents and other supplies are stored and disposed of properly. An inventory list is maintained with preferred and backup suppliers. | □ Yes □ No | |
| Key quality indicators for the preanalytic, analytic, and postanalytic testing phases have been identified and are tracked, with number and percentage of errors and nonconformities evaluated at routine intervals against predefined goals. Smaller laboratories may choose to keep an incident log. | □ Yes □ No | |
| Preventive and corrective actions are taken as appropriate to decrease errors, with scheduled periodic review to assess the effectiveness of these actions. | □ Yes □ No | |
| SOPs and the TQMS are reviewed for potential updates or improvements at predetermined intervals. Such reviews will include staff and client feedback and evaluation of any changes implemented since the previous review. | □ Yes □ No |
