Dear API Abby:

I do my best to submit successful proficiency testing results, but I often seem to get dinged due to clerical errors. Is this a common issue among laboratories? What steps can I take to reduce these errors and improve my performance?

Clerically Yours

Dear Clerically Yours:

You are not alone! Clerical errors remain one of the most common reasons laboratories receive unsatisfactory proficiency testing scores. Studies have shown that a substantial proportion of proficiency testing failures stem from transcription or reporting errors, rather than analytical problems with the testing. For example, one laboratory study found that 44% of unacceptable proficiency testing submissions were caused by clerical errors.¹

The good news is that these errors are highly preventable. Make it a habit to double check your results before submitting them by carefully reviewing all written words, numbers, units, and methods. You may be surprised by how often a quick review uncovers a clerical error that would have otherwise gone unnoticed. This practice is especially important if your laboratory transcribes patient results into a medical record. After all, if you were the patient receiving those results, you would want the information reported accurately and correctly.

Another effective strategy is to have a second person review the results prior to submission. Ask them to pay careful attention to decimal places, instrument and methods selection, transcription accuracy, and confirming the unit of measure the result is reported in.

If you’re lucky, your proficiency testing provider offers a process that eliminates the need for manual entry of data. Using this approach, your laboratory would register its proficiency testing samples through its own laboratory information system. From there, your laboratory can order and complete the testing, export the proficiency testing data, and upload it directly to the proficiency testing provider, where the results are evaluated. Not only is manual entry eliminated, but your laboratory will save time and resources. Ask your proficiency testing provider if they have such a system – and if it is offered free-of-charge.

Dear API Abby:

My laboratory is trying to figure out how best to learn from our proficiency testing failures. Is it acceptable troubleshooting to repeat the proficiency testing samples?

Baby One More Time

Dear Baby:

When investigating a proficiency testing failure, you should focus on identifying the root cause rather than simply correcting the immediate problem. Chances are, if the source of the error is not addressed, the problem will resurface later. Start by comparing the tested results with the reported results to determine whether a clerical or transcription error occurred. If the failure was due to a reporting mistake, you'll need to determine how and where the error occurred and whether additional safeguards should be implemented.

It is also important to evaluate any human factors that may have contributed to the failure. Verify that testing personnel followed the laboratory's standard operating procedures, used the correct methodology, and complied with all proficiency testing provider instructions for testing and reporting results.

Next, review all quality control data generated before, during, and after the proficiency testing event to determine whether there was any indication of test system instability or variability. Examine instrument maintenance logs, calibration records, reagent lot numbers and expiration dates, and any recent changes to testing procedures. It is also valuable to consider whether specimen handling, sample preparation, environmental conditions, workflow interruptions, or other unusual circumstances may have affected the results.

Once the root cause has been identified, your laboratory should develop a corrective action plan that directly addresses the issue. This may include staff retraining, procedure revisions, additional quality checks, instrument maintenance, or changes to documentation and reporting processes.

Finally, assess whether the root cause could have affected patient testing and determine whether any follow-up actions are necessary. A thorough, well-documented investigation not only helps prevent future proficiency testing failures but also strengthens the overall quality and reliability of your laboratory's testing program.

Dear API Abby:

We are so excited to welcome a new cohort of medical laboratory professionals into our ranks! As part of our introductory training, we want these new employees to be well-versed in proficiency testing. Do you have suggestions for how to tackle this job?

Welcome Wagoner

Dear Wagoner:

Congratulations on your new hires! Given its significance to the laboratory, you are smart to include proficiency testing as part of their introductory training. Here are a few suggestions for getting started.

Number one: explain the purpose of proficiency testing! Your new colleagues should recognize that proficiency testing exists to verify the accuracy and reliability of patient testing by evaluating the laboratory’s ability to analyze unknown samples. It’s not just a matter of regulations or rules, although these should certainly be covered. Proficiency testing is an important quality assurance tool that can help identify real problems before they impact patient care.

Next, develop and share written procedures that clearly describe the proficiency testing process. Help your staff understand what to do when samples are received and how they should be handled and stored. Clearly state the time frames for documenting and submitting results, and identify who is responsible for each step. If there is a proficiency testing failure, staff should also be aware of the appropriate corrective actions to take.

It is equally important to review the "dos and don'ts" of proficiency testing. New employees should understand that proficiency testing samples must be tested in the same manner as patient specimens unless the proficiency testing provider’s instructions specify otherwise. They should never seek assistance from another laboratory, share results before the submission deadline, or intentionally alter testing practices during a proficiency testing event. Understanding these expectations early can help prevent serious compliance issues later.

Consider incorporating real-world examples into your training. Reviewing past proficiency testing successes, common mistakes, and corrective action investigations can help new employees appreciate how even small errors, such as transcription mistakes or incorrect result entry, can affect proficiency testing performance.

Good luck with the training. The future of medical laboratory science is bright and your investment in teaching proficiency testing fundamentals will help ensure your newest team members get off to a successful start.

Reference

1. Xu P, Wu F, Lewis C. Counting CAP deficiency caused by clerical errors: a regional study. Clinical Chemistry. 2025;71(1). doi:10.1093/clinchem/hvaf086.17.