What it is, what to expect, and what to look for
Your new testing facility is working toward accreditation and needs to be accredited. Testing accreditation often comes with one requirement you might not have planned for: proficiency testing (or PT). What is it, what should you look for in a PT provider, and what should you expect once you have one?
What is Proficiency Testing?
In the world of engineering, there’s something called an “end-to-end test”. End-to-end testing is what happens after you’ve tested all the pieces of your new product individually and you’re ready to make sure they all work together. Sure, you could take that new car on a cross-country road trip straight away, but let’s make sure it can do a few laps around the test track first and make sure we haven’t missed anything.
While your lab isn’t made up of manufactured parts like a car, it does have equipment, protocols, and staff that all have to work effectively together. Every so often, it’s important to take your lab back to the proverbial test track to make sure everything is working as expected. To test your equipment, there are calibrations and diagnostics. To test staff, there are exams and continuing education. Once you’ve verified that all the pieces work individually, proficiency testing ensures they work as a whole.
The way this works is simple. Let’s say you run a point-of-care testing site that tests swabs for Group A Strep. Your lab will sign up with a PT provider for a Group A Strep program. Several times per year, the provider will send a set of samples for you to test. The PT provider knows what’s in the sample and you don’t. Your job is to test it like normal and report the results. Different programs are offered depending which analytes your site tests for (e.g. Group A Strep, Group B Strep, Flu, RSV, Shiga Toxin, etc.) Some PT programs are panels that challenge a range of analytes, such as our Gastrointestinal Panel, in which the sample could contain one of a number of organisms that cause infectious diarrhea.
What to Expect?
Your PT provider should communicate in advance the expected shipping date and the due date for each shipment. If there are requirements around receiving samples, those should be communicated as well. And, just like real patient samples, some PT samples have a shelf-life! Your provider should tell you how long the sample is stable for, and your lab make sure to test the sample within that timeframe.
Some PT providers have special instructions for preparing their samples. You may have to mix the contents of two containers, rehydrate and culture a lyophilized sample, or something else. Generally, we believe that testing simulated samples better reflects and exercises a lab’s abilities than having them prepare and test a lyophilized sample.
If you’re in Canada or the United States, you can expect to receive two to three PT shipments per year. Each shipment will include several samples to be tested and reported. Labs in the US are required by CLIA requirements to perform PT three times a year, with five samples in each shipment. So, if you choose a provider in the states (whether or not your lab is in the states,) you’ll be paying for and performing three tests per year on five samples each. In most provinces in Canada, however, labs are only required to perform proficiency testing twice per year for most testing programs, which a Canadian provider should be able to accommodate.
Some PT providers can arrange for customizations of schemes, or even altogether custom programs. If your lab only tests for one specific organism in a panel, for instance, you may be able to request that they only send your lab that organism, and that they grade your lab accordingly.
If your lab reports an incorrect result, a PT provider will let you know. They are also required to inform your accrediting body of a failed result. But don’t panic! This doesn’t mean you’re in trouble. We’ve written an article about what happens when you fail a PT challenge and what to do about it.
Finally, expect your PT provider to be a partner who works with you, rather than an intrusive observer looming over your shoulder, searching for the slightest mistake. The goal of PT is not to punish labs, it’s to help you catch the mistakes that we are all capable of making and, in doing so, safeguard patients and customers. PT providers are here to look out for you and help you learn, not to punish you when you make a mistake.
What Should You Look for in a PT Provider?
Here are a few things to look out for when choosing your PT provider. Keep in mind that PT programs typically last for one full year, so while you’ll be stuck with a provider for a year, you’ll be able to change your mind next year. Changing your PT provider usually involves sending a notice to your accrediting body, and isn’t much work, but you’ll have to check with the accrediting body to be sure.
- Accreditation: what are your accrediting body’s requirements for PT? And how do a given PT provider’s programs line up with those requirements? Are they shipping you more samples than you need? Fewer? And if there is a discrepancy, are they willing to be flexible and adjust the price?
- Distance: how local is your PT provider? And how much do they charge for shipping? Shipping fees are often added on top of the cost of PT samples themselves, and can represent a significant cost. If samples are crossing a border, find out what happens if they get held up in customs for an extended period. It doesn’t happen often, but it’s good to find out.
- Program cost: the cost of a PT program can vary from provider to provider. It’s worth comparing prices from several different providers (make sure you include shipping!) before making your decision.
- Reporting: what is your PT provider’s process for submitting results? And what do they send in response?
- Programs: does the provider have the programs you’re looking for? Are they willing to make customizations if you need them?
- Replacements: what is your provider’s policy regarding replacement samples when something goes wrong?
- Appeals: what is the provider’s appeals process if you disagree with their assessment of their results?
There is a lot to consider when choosing a proficiency testing provider, but this primer should get you started. Of course, we would be happy to discuss your proficiency testing needs. The most important thing is that you choose a provider whose programs work for you and your lab.
