Top of page Content begins here

Proficiency Testing

About CPQA’s proficiency testing program

What is Proficiency Testing?

Protocols that involve the real-time reporting of participant drug concentrations for the purposes of diagnosis, treatment, and/or safety decisions are considered a clinical test under the Clinical Laboratory Improvement Amendments of 1988 (CLIA 88). Laboratories performing clinical pharmacology assays for these purposes are required by the Centers for Medicare and Medicaid Services (CMS) to maintain CLIA certification. One requirement for CLIA certification is participation in a proficiency testing program. A proficiency testing program is a program to monitor a laboratory’s readiness and ability to obtain reproducible and accurate results.

In addition, it is important that analyte specific results across multiple laboratories are equivalent and within a predetermined range of variability if they are combined for analysis or compared. The National Institutes of Health has implemented initiatives to assure NIH funded research results are rigorous and reproducible; proficiency testing is a tool that proves competency of the laboratories to achieve both.

Back to top

What is the Role of CPQA?

The CPQA PT Program is ANAB ISO17043 accredited and offers a proficiency testing program for antiretroviral (ARV) and tuberculosis (TB) drugs often used together in treatment of patients with HIV-1 and TB. As needed, other drugs used in the treatment of HIV may be added to the Proficiency Testing panels for analysis. Participation in CPQA meets the proficiency testing requirement for CLIA certification, and ISO15189 for many laboratories that perform clinical pharmacology assays for HIV clinical trials.

Clinical trial networks that participate in the CPQA program include ACTG, HPTN, HVTN, and IMPAACT.

Back to top

How Does the CPQA Proficiency Testing Program Work?

Twice per year, CPQA organizes proficiency testing panels. Laboratories that plan to participate indicate to CPQA what analytes they need to test using their methods. CPQA then sends each laboratory samples that have a drug concentration known by CPQA but not by the laboratory. The laboratory tests the specimen and sends results back to CPQA. At the end of the testing round, CPQA prepares a report for participating laboratories and DAIDS network leadership with the proficiency results. The report is blinded so that laboratories can only identify their own results.

Participating laboratories are given two reports. The first report is sent just to laboratories and contains a blind listing of results (although the laboratory is told which results are theirs). If there was an issue during testing, the laboratory will be required to investigate and provide an explanation and corrective action plan to mitigate the issue in the future.

After the labs have had the opportunity to review their results and provide comments as necessary, CPQA prepares a second report. This second report is shared with laboratories and network leadership, and contains a detailed introduction that examines the results, as well as charts and graphs to help understand the results.

Back to top

Analytes Currently Offered

CPQA currently offers proficiency testing for the following drug analytes.

abacavir (ABC)
atazanavir (ATV)
bictegravir (BIC)
cabotegravir (CAB)
darunavir (DRV)
dolutegravir (DTG)
efavirenz (EFV)
emtricitabine (FTC)
lamivudine (3TC)
lopinavir (LPV)
nevirapine (NVP)
raltegravir (RGV)
rifampicin (RMP)
rilpivirine (RPV)
ritonavir (RTV)
tenofovir (TFV)

For questions about analytes, contact us.

Back to top


In situations where a laboratory is unsatisfactory for an analyte they are required to discontinue testing the analyte until a complete investigation has been made as to the reason for the failure. CPQA offers remediation support in cases where a laboratory has scored unsatisfactory due to methodological problems for an analyte(s).

After the laboratory contacts CPQA to arrange for remediation support, CPQA will review the longitudinal proficiency testing analyte(s) data and provide a remediation tailored to specifically resolve suspected issues (such as specificity-driven and concentration trending) as well as generally assure continued accuracy and precision.

Back to top