It’s one of the most common phrases you hear from your health care practitioner: “I just want to run a few tests.”

Laboratory tests are among the most important and pervasive aspects of modern medicine. The results of clinical laboratory tests contribute to the majority of healthcare decisions. Laboratory tests provide healthcare practitioners with the information for decisions from diagnosis through therapy and determining outlook (prognosis). For some conditions, there is just no substitute for a laboratory test. For example, high cholesterol can be identified through laboratory work long before any symptoms might appear.

Healthcare practitioners rely on the laboratory for help in diagnosing any number of conditions and for managing their treatment. They trust the results that laboratories produce. But you’ve probably seen headlines or heard stories about patients who suffered dire consequences, such as unnecessary surgery or even death, as a result of inaccurate laboratory test results or incorrect interpretation of the results. So, a reasonable question for any patient is: should I trust my laboratory results?

The short answer is yes, you can have as much trust in these results as your health care practitioner does. There are many protections in place to ensure that laboratories produce reliable results. These have been instituted by federal and state government, laboratory accrediting organizations, and individual laboratories themselves to help maintain standards of quality. In addition, there are steps that you personally can take to further increase your comfort with the quality of your laboratory results, including questions that you can ask your healthcare practitioner.

Regulations: The Key Players

Federal Government

All laboratories that perform tests on “specimens derived from humans for the purpose of providing information for the diagnosis, prevention, and treatment of disease” fall under the Clinical Laboratory Improvement Amendments (CLIA). This means that if your healthcare practitioner wants to run a blood test or urinalysis, or asks you for a stool or sputum sample, then CLIA will influence how these samples are handled and how the tests are performed.

Passed by Congress in 1988, CLIA was adopted to ensure the accuracy, reliability, and timeliness of patient test results. CLIA covers testing in all U.S. states, and every clinical laboratory in the country must obtain a CLIA certificate appropriate for the complexity of tests that the particular laboratory can perform. The various types of CLIA certificates are described in the next section.

Three federal government agencies have roles in clinical laboratory oversight.

  • The CLIA program is housed within the Centers for Medicare and Medicaid Services (CMS) Center for Clinical Standards and Quality.
  • Laboratory test complexity is generally determined by the Food and Drug Administration (FDA). The FDA classifies tests as waived, moderate, or high complexity.
  • A third federal government agency that has a role in laboratory oversight is the Centers for Disease Control and Prevention (CDC). This agency provides scientific support to the CLIA program.

State Government

Two states, New York and Washington, have state laboratory regulations that are equal to or more stringent than those outlined in the CLIA regulations. These states have gone through a rigorous process to be recognized by the federal government and are referred to as CLIA “exempt” states, due to the fact that the state regulations meet or exceed the CLIA regulations. In these cases, the state, not the federal government, assumes primary responsibility for oversight of laboratory practices. This situation can occur only after the Centers for Medicare and Medicaid Services (CMS) have “deemed” the state requirements to be equal to or more stringent than the CLIA requirements.

Several other states have requirements that are above and beyond the CLIA regulations, such as requirement to obtain a state laboratory license in addition to the federal CLIA certificate, and laboratory personnel licensure requirements.

Laboratory Accrediting Organizations

The most visible line of defense for accurate results is federal regulation, but several laboratory accrediting organizations have laboratory standards that are equal to or more stringent than CLIA and have been “deemed” by CMS to oversee laboratories that are enrolled in their accreditation programs.

The federal government oversees the performance of the “deemed” accrediting organizations in several ways. Accrediting organizations with “deemed” status must apply for reapproval on a regular basis to demonstrate that their standards continue to be equal to or more stringent than CLIA. The federal government also provides oversight of the accrediting organizations by performing validation surveys. This means that a CLIA inspector will inspect a lab within 90 days of the inspection date of the accrediting organization. When there are significant deficiencies identified by the CLIA inspector, the findings of the two agencies for that laboratory will be compared. CMS will then calculate an annual “disparity rate” for the accrediting agency, which must be under a disparity threshold established by the CLIA regulations.

Two accrediting organizations, the College of American Pathologists (CAP) and The Joint Commission, had stringent, voluntary laboratory accreditation programs many years before the government required it. Today, more organizations offer highly respected laboratory accreditation programs, including COLA, AABB, the American Association for Laboratory Accreditation (A2LA), the American Osteopathic Association/Healthcare Facilities Accreditation Program (AOA/HFAP), and the American Society for Histocompatibility and Immunogenetics.

Other organizations, such as the Clinical Laboratory Standards Institute (CLSI), a globally recognized, standards-developing organization, are involved in improving medical testing through the development and dissemination of standards, guidelines, and best practices.

AACC, the American Society for Clinical Pathologists (ASCP), the American Society for Clinical Laboratory Scientists (ASCLS), and the Clinical Laboratory Management Association (CLMA) are other examples of laboratory professional organizations that provide education and resources for laboratories and laboratory scientists.

Key Components of Lab Oversight

CLIA Certificates

There are several types of CLIA certificates, all issued by the federal government. All laboratories performing clinical testing are required to obtain the type of CLIA certificate appropriate for their laboratory.

  • Certificate of Waiver – This is the type of CLIA certificate required for laboratories that perform only “waived” tests. Laboratory tests that have been approved as “waived” by the FDA are simple tests that have an insignificant risk of erroneous results. For example, pregnancy tests that can be purchased in a drug store are considered “waived.” Laboratories with a CLIA certificate of waiver do not undergo routine federal inspections, and there are very few federal regulatory requirements for the performance of waived tests.
  • Certificate of Provider Performed Microscopy Procedures (PPMP) – The CLIA regulations define a subset of tests as PPMP tests. This includes a limited number of microscopic examinations that are classified as PPMP when performed by a health care practitioner. Laboratories with a CLIA PPMP certificate can perform PPMP and waived tests. These laboratories do not undergo routine federal inspections, but there are federal regulatory requirements covering PPMP tests.
  • Certificate of Compliance – Laboratories that perform a higher level of testing, either moderate complexity and/or high complexity, as classified by the FDA, must obtain either a CLIA certificate of compliance or a CLIA certificate of accreditation. Laboratories performing moderate and/or high complexity tests that choose to be inspected by the state agency for adherence to the CLIA regulations and any applicable state regulations have a CLIA certificate of compliance.
  • Certificate of Accreditation – Laboratories performing moderate and/or high complexity tests that choose to enroll with a CMS approved accrediting organization for oversight and inspection have a CLIA certificate of accreditation.

Laboratories with certificates of compliance or accreditation have many more stringent regulatory requirements than laboratories with waived or PPMP certificates, including more stringent personnel qualification requirements. Laboratories with certificates of compliance or accreditation may perform all levels of testing, including waived, PPMP, moderate complexity, and high complexity testing.

All laboratories, no matter which type of CLIA certificate they have, must designate a qualified Laboratory Director. The Laboratory Director is responsible for the overall operation of the laboratory. The qualifications necessary to be a Laboratory Director depend on the highest level of testing performed in the laboratory; the higher the level of complexity performed, the more stringent the qualification requirements for the Laboratory Director. There are other required laboratory positions, each with responsibilities defined in the CLIA regulations.

Laboratory Inspections

To make sure that laboratories are following the requirements outlined in CLIA, state law, and/or the rules established by the accrediting organizations to qualify for their accreditation, laboratories performing moderate and/or high complexity testing also must undergo regular inspections every two years. Several particularly important areas for inspection are leadership, personnel training and competency requirements, proficiency testing, performance improvement, and quality control requirements. These inspections may be unannounced to eliminate any opportunity for the laboratory to “ramp up” for the inspection. Unannounced inspections assure that the laboratory is in a continual state of readiness to provide safe, quality care to all patients.

  • Education and Training Requirements – There are many roles to fill in a laboratory, and both the voluntary systems and the federal regulations spell out educational requirements for laboratory personnel, such as the minimum educational level that a person must have in order to perform each level of laboratory tests. In addition, laboratory personnel may be certified for their profession, obtained through successful completion of a national certification exam. Similarly, laboratory testing personnel are required to undergo orientation and ongoing training to ensure competencies for each test they are performing. Documentation of these training and competency records are reviewed very carefully during inspections and surveys. Some states require state licensure for laboratory personnel and may require documented continuing education. For more information on laboratory personnel, their various roles and education requirements, read our article Medical Laboratory Professionals: Who’s Who in the Lab.
  • Proficiency Testing – Laboratories that perform the kinds of tests typical of a hospital laboratory participate in a proficiency testing (PT) program. For this program, an outside agency approved by the federal government, called a PT practitioner, checks on the accuracy of the laboratory’s test results by sending test samples to be analyzed. The outside agency knows the levels of the substances, or analytes, contained in the samples – the sodium level, for example – but the laboratory does not. PT includes samples for each specialty and subspecialty area in which the laboratory performs testing. The laboratory must test the samples the same way it would test patients’ specimens. The outside agency uses PT to grade the laboratory’s accuracy. Laboratory inspectors verify that the lab has successfully participated in an approved PT program.
  • Quality Control – To ensure the quality of the results, clinical laboratories test “control” samples along with the patient samples. The laboratorians know what these control samples contain, so the samples provide a built-in check on the process of analysis, which in many cases is carried out by an automated instrument called an analyzer. The control samples contain different levels of concentrations of the analyte being measured, to make sure the analyzer is running correctly across the range of concentrations the patient samples may contain. If the results vary from the known quantities, the laboratorians know there is a problem. The problem identified must be corrected before patient testing can be reported. As a general rule, no patient results are reported without passing the required quality control for each laboratory test. Laboratory inspectors also examine these records during their evaluations.
  • National Patient Safety Goals – The goals highlight problematic areas in all phases of the laboratory testing and describe evidence and expert-based solutions to these problems. The purpose of these National Patient Safety Goals is to promote specific improvements in patient safety. For example, correct patient identification is one of the goals that must be met throughout the process for specimen collection, analysis, and result reporting.

Making Improvements

Following an inspection or survey of a laboratory, the state agency or the accrediting organization will provide the laboratory with a list of any area in which they did not meet requirements (noncompliances), or deficiencies identified during the inspection. The laboratory will be required to make improvements to bring them in to compliance with requirements. Laboratories must then submit documentation or a plan of correction to address the inspection findings. State agencies and accrediting organizations offer support and guidance during the post-survey period to help the laboratory staff understand the requirements and make sure that their plan of correction is implemented correctly.

State agencies and accrediting organizations also often leave the laboratories with recommendations on how they can improve their processes or be more efficient.

Sometimes laboratories are re-inspected a few months after the initial inspection, so that the state agency or accrediting organization can assure that the lab has implemented acceptable corrective actions.

Your Role

CLIA regulations create a “level playing field” in which all laboratories must meet appropriate criteria in competing with each other. However, the quality of services still varies among laboratories. To ensure that you are receiving the best quality services, there are steps you can take to check for yourself.

  • Your first consideration is the kind of laboratory that will be testing your specimen. Most physician office laboratories run only waived tests. Education or training requirements for the personnel performing only waived testing vary, depending on the accreditation organization requirements, but are generally less stringent. Ask your healthcare practitioner about the qualifications of those staffing the laboratory. Also ask if the laboratory participates in any outside education or quality checking programs.
  • The major federal requirement for labs that perform only waived tests is that they follow the manufacturer’s instructions for the tests. However, a recent U.S. Health and Human Services Department study found that nearly one-half failed to do so. Can the person who will perform your test explain to you the specified procedures? Is the laboratory following proper specimen labeling and handling procedures (for example, was your specimen labeled with your name in your presence)?
  • If your tests will be run by a larger, more complex laboratory, it will undoubtedly fall under the most stringent CLIA accreditation requirements, but you still might like reassurance about its quality. Ask your health care practitioner about what considerations went into the choice of the laboratory. What criteria did your healthcare practitioner use? How long has your practitioner been dealing with this laboratory? How is your practitioner assured of the accuracy of the test results?
  • The sample collection process itself should provide you some clues: was the specimen properly labeled? Were you given clear and adequate instructions if you collected the sample yourself? When you have blood drawn, you can ask to see the labeled collection tubes before they are taken away. That way you can verify that your specimen is accurately labeled. The person collecting your sample should always verify your identity. This is why, even if they know you, they may ask you to verify your name and date of birth.
  • Is your health care practitioner aware of the laboratory’s accreditation status? Because laboratories are so closely regulated, if you’d like reassurance on the laboratory’s accreditation and certification, you can check this yourself by visiting various web sites. The U.S. Centers for Medicare and Medicaid Services posts a list of accredited laboratories as well as those that have had some trouble. Through the links listed in Related Content below, you can find other inspection and certification agencies that might have further information on the laboratory you’re interested in.

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