We had it done because it was the only option for us. We had to mail it from Asia to England. It was cheap, and seemed fairly accurate, showing one new thing that we didn't know about and showing all the ones we were 100% sure about. That said, it didn't change much with the eczema. Still the same. So, I am thinking that we are dealing with more than just allergies.
Hope it works for you. Even if it has false positives, you can eliminate and reintroduce.
Have you tried eliminating the top 8? Or just start by eliminating dairy and gluten? Then, if she still has issues, eggs? Those three seem to be responsible for a lot of eczema cases. Also, keep in mind that dairy and gluten takes weeks to months to get out of your system. We saw some improvement after two months.