Proficiency Testing

Proficiency testing (PT), mandated by Clinical Laboratory Improvement Amendments (CLIA) '88, is a source of external quality control. This practice of testing unknown specimens from an outside source provides an additional means to assure quality laboratory testing results. Although laboratories perform daily internal quality control with their test systems, external quality control provides important interlaboratory comparisons to determine the accuracy and reliability of the testing procedures.

For laboratories applying for an initial Medical Test Site (MTS) license (non-waived or non-PPMP categories), proof of enrollment in an approved PT program must be submitted to the MTS Program before the MTS license can be issued.

Proficiency Testing Frequently Asked Questions

Approved Proficiency Testing Providers

CLIA provides a list of approved proficiency testing programs (PDF).

Enrollment Requirements

Except where there is no available Proficiency Testing (PT) program or PT is not required, each Medical Test Site (MTS) shall demonstrate satisfactory participation in a Federal Health and Human Services Centers for Medicare and Medicaid Services (CMS) approved PT program, appropriate for the tests performed on-site, excluding waived tests. (Note: Bacteriology, Mycology, Mycobacteriology: these subspecialties do not have "regulated analytes" per se. However, the laboratory must subscribe to a module that covers the testing performed.) The MTS must enroll each year. If the MTS is currently enrolled in an approved PT program, the provider will automatically send a renewal form for the next year in the fall of the year.

For non-regulated analytes or tests for which there is no PT available, the MTS must have a system for biannual verification of the accuracy of its test results. This may be accomplished by analyzing specimens from a PT company or reference laboratory, by comparing split samples with a reference laboratory, by performing patient correlation, etc. At least two specimens should be used for test verification every six months.

Medical Test Sites (MTS) will monitor performance throughout the year for regulated analytes. During the on-site survey, unregulated/ungraded tests will be reviewed to see if: (1) laboratory is reviewing PT results for these tests; (2) any problems have been noted by the laboratory; and, (3) corrective action has been taken when indicated. The laboratory may be cited if it is not reviewing the unregulated/ungraded tests and/or has not taken appropriate corrective action when problems are noted.

Performance Requirements

Number of Challenges: The Proficiency Testing (PT) programs are required to provide a minimum of five samples per testing event, with three testing events per year.

Minimum acceptable score for satisfactory participation:

• Microbiology, General Immunology, Syphilis Serology, Routine Chemistry, Endocrinology, Toxicology and Hematology:
  • 80% overall testing event score for all specialties
  • 80% for each analyte
  • 100% for HIV testing
• Immunohematology:
  • 100% for each analyte and overall testing event score for ABO (test used to type blood – either A, B, or O) group and D(Rho) typing
  • 100% overall testing event score for compatibility testing and unexpected antibody detection
  • 80% overall testing event score for antibody identification

Unsatisfactory Performance

• Unsatisfactory analyte score;
• Unsatisfactory PT event or overall score for a specialty or subspecialty;
• Failure to participate in a testing event; or
• Failure to return PT results within specified timeframe.

Unsuccessful Participation

Failure to achieve satisfactory performance (overall testing event score or analyte score, where applicable) for two consecutive testing events or two out of three consecutive events.

Repeated Unsuccessful Participation

When unsuccessful participation occurs repeatedly for an analyte, specialty, or subspecialty, the department will require the laboratory to cease testing for that analyte, specialty or subspecialty. The laboratory will be required to cease testing for a minimum of six months

Actions to Be Taken for Unsuccessful Participation

1. Medical Test Sites (MTS) program staff will send the laboratory a letter identifying the problem and stating that the laboratory may choose to discontinue patient testing for the identified test, specialty or subspecialty or follow a directed plan of correction (options listed in the letter). The MTS is required to perform a retrospective review of all patient samples to determine if patient results were compromised in any way due to issues with the test system.
2. The laboratory shall notify the department, in writing, within 15 days of receipt of the notice, of the decision to discontinue testing patient specimens for the identified test, subspecialty or specialty or to agree to a directed plan of correction. If a laboratory fails to respond within fifteen days, the department will notify the laboratory by letter, or by phone, that its response is overdue. When the response is received, the MTS program will review the response and, if acceptable, notify the laboratory that its request has been accepted. If the plan is unacceptable, the MTS program will contact the laboratory to discuss obtaining an acceptable response. If no response is received within five days of the receipt of the letter/phone call, appropriate disciplinary action will be initiated.
3. The laboratory will have 45 days from receipt of the first letter to complete the corrective actions that are agreed upon between the MTS and the department.
4. If the laboratory chooses to discontinue patient testing for the identified test, the director may petition for reinstatement after satisfactory performance in two successive events. The department shall notify the laboratory in writing, within 15 days of receipt of the petition, of its decision related to reinstatement.

Directed Plan of Correction

If a laboratory has failed two consecutive testing events or two out of three consecutive events of PT, the MTS program may give the laboratory options rather than require it to discontinue patient testing. These options may be any one or a combination of the following:

1. Undertake appropriate training for the testing personnel involved;
2. Employ technical assistance necessary to correct PT problem; or
3. Perform special studies such as:
   • Testing 10 or more patient specimens from its reference laboratory; or
   • Obtaining and analyzing additional PT material from a PT agency.

NOTE: For special studies, the laboratory must submit the results and a statistical analysis of the results to The program. The MTS program will review the data to determine if the laboratory has performed satisfactorily on the special study.

When the MTS program determines that the laboratory has successfully completed its directed plan of correction, a letter will be sent stating that results are acceptable and the laboratory may continue testing patient specimens for the analyte(s), specialty, or subspecialty. The letter will also inform the laboratory that if it receives an unsatisfactory grade on either of the next two sets of PT, it will be required to discontinue testing until it passes two consecutive sets of PT.

If a laboratory fails to respond within 15 days, the MTS program will notify the laboratory by letter that its response is overdue. If no response is received within five days of the receipt of the letter, appropriate disciplinary action will be initiated.

A laboratory may be offered a directed plan of correction only once for an analyte(s). If there is a failure in either of the next two events for the same analyte, the laboratory will be required to discontinue patient testing until it successfully passes two consecutive sets of PT for that analyte.

If it is discovered during an on-site survey that a laboratory has not enrolled in an approved PT program, a deficiency will be written. The only acceptable plan of correction (POC) is immediate enrollment in PT with proof of enrollment sent along with the POC.

Disciplinary Action

If a laboratory refuses to voluntarily discontinue testing patient specimens when it has been notified to do so, or does not respond in writing to the notification, the MTS program will begin enforcement action.

Proficiency Testing Monitoring

The Medical Test Sites (MTS) program monitors proficiency testing (PT) performance according to the Clinical Laboratory Improvement Amendments (CLIA) requirements for PT.

Laboratories must authorize their proficiency testing company to release their PT results to the MTS program for monitoring. This is done at the time of enrollment in the PT program for the current year. If the PT company does not send copies of PT results to Lthe MTS program QA for monitoring, the laboratory will receive an unsatisfactory grade for non-participation and may jeopardize the facility's Medical Test Site license. The MTS program will notify the federal Health and Human Services Centers for Medicare & Medicaid Services (CMS) of any adverse actions relating to PT; this information will be published by CMS in its annual Laboratory Registry Report.

Regulated Analytes

Listed below are current regulated analytes as defined by the Centers for Disease Control and Prevention.

These tests must be covered by Proficiency Testing.

Chemistry ALT/SGPT Albumin Alkaline phosphatase Amylase AST/SGOT Bilirubin, total (or neonatal) Blood gas pO2, pCO2, pH Calcium, total Chloride Cholesterol, total HDL Cholesterol Creatine kinase Creatine kinase isoenzymes Creatinine Glucose Iron, total LDH LDH isoenzymes Magnesium Potassium Sodium Total Protein Triglycerides Urea Nitrogen Uric Acid Endocrinology Cortisol Free Thyroxine Serum Pregnancy (HCG) (qualitative or quantitative) T3 Uptake Triiodothyronine TSH Thyroxine

Toxicology Alcohol, blood Blood lead Carbamazepine Digoxin Ethosuximide Gentamicin Lithium Phenobarbital Phenytoin Primidone Procainamide/metabolite Quinidine Tobramycin Theophylline Valproic Acid Hematology Cell Identification Auto/manual WBC differential Erythrocyte Count (RBC) Hematocrit (automated) Hemoglobin Leukocyte count (WBC) Platelet Count Fibrinogen Partial thromboplastin time Prothrombin time Immunohematology ABO Group D (Rh typing) Antibody Detection Compatibility testing Antibody Identification Syphilis Serology RPR, VDRL, MHA-TP, etc.

Immunology Alpha-1 antitrypsin AFP (tumor marker) Antinuclear antibody ASO HIV Complement C3, C4 HBsAg, Anti-HBc, HBeAg IgA, IgE, IgG, IgM Infectious mononucleosis Rheumatoid factor Rubella Bacteriology Cover the Specialty according to the different types of testing performed Mycology Cover the Specialty according to the different types of testing performed Parasitology Direct only Concentration/Stain Virology HSV EIA Culture or FA Other EIA for virus Mycobacteriology Over the Specialty according to the different types of testing performed