On behalf of the authors, I thank Ms. Deborah Gwynn for the comments about our study that was the subject of a recent report by the VIN News Service ("Study finds pet 'stress scan' gives unreliable results," Jan. 31, 2019). However, the response provided by Glacier Peak Holistics ("Glacier Peak Holistics responds to criticism of its test," Feb. 5, 2019) appears to miss the point of our findings. We do not care how or why the biofeedback device might work. We only care if the test could differentiate allergic from healthy animals and if the results were reproducible, and therefore helpful, in the diagnosis or treatment of pets.

Our study demonstrates that the Glacier Peak Pet Wellness Life Stress Scan cannot differentiate healthy or allergic dogs, and cannot even provide the same results for the same animals.

I will use an example to help explain our findings. Imagine I want to see where my ancestors came from. I submit a sample to a genealogy company. My brothers and sisters submit samples, too. All of our reports should be similar — after all, we came from the same parents and have the same ancestors. But, my ancestry report would look very different from that of my study co-authors, because they come from very different parts of the world. And if we submitted samples from our dogs, the ancestry report for our dogs should look very different from our own.

Now, if each of us submitted two samples, I would hope that each of these pairs of samples would produce the exact same (or very nearly identical) results. After all, in each case, it’s a sample from the same person. If the ancestry test didn't, then that's not a useful ancestry test. After all, which result should I believe? The first or the second? Or neither?

This is what we found with the Glacier Peak Life Stress Scan. None of the samples we submitted twice produced results that were any more similar to each other than to any other sample.

But it gets even more intriguing. Going back to the ancestry example, it wouldn’t make sense if the reports for myself and my co-authors, all of our brothers and sisters, and all of our dogs were similar. Again, this is what we found with the Glacier Peak Life Stress Scan. For almost every sample submitted, certain substances were reported as "triggers." This happened whether the sample was from a healthy dog, allergic dog, or toy stuffed dog. On the other hand, some substances, such as nuts and many fruits, almost never showed up in any of the reports as "triggers."

Unrelated to our results, Ms. Gwynn’s letter refers to "numerous clinical trials" on the SCIO device manufactured by Quantum World Vision, and a report by Professor Desire Dubounet of IMUNE. I encourage readers to look at this article from The Seattle Times, "How one man's invention is part of a growing worldwide scam that snares the desperately ill."

I also encourage readers to do a web search on "Dubounet" and "William Nelson." I will let readers judge for themselves how credible they think this person's science is.

As for the SCIO system, readers can view other products that Quantum World Vision also sells: Cryxon Crystal Light Therapy and The Quantum Prayer Wheel.

Mark Rishniw, BVSc, MS, PhD, DACVIM, is co-author of the study "Hair and saliva analysis fails to accurately identify atopic dogs or differentiate real and fake samples," published online Jan. 24, 2019, in the journal Veterinary Dermatology.