It is an odd system. Seems to have its own rules. I tend to write for explanations & argue persuasively. Gets rid of bills regularly. Separate lab bills are the weirdest ones. I approach all odd bills about the same. I call and ask what the bill is for (itemized) and how I authorized it. Sometimes it makes sense and I pay it. Often it doesn't and I get a runaround. Step 2 I write and ask for specifics and exactly how I authorized that I be billed. I point out that generally they'll be a signature or some other evidence of a contract. That usually gets me no note and a copy of a diagnostic sheet or lab sheet or something with boxes checked off and strange writings. None of it really seeming to tie to anyone. Generally the ordering doctor's name is either illegible or someone I've never heard of. Step 3 I write back with copies of all previous communications and a letter disclaiming responsibility for the bill because there's nothing showing I authorized it and nothing in English demonstrating I received any services. I rarely get a response, and after a few months the bills stop coming. Once I had a collection agency call and I faxed them a copy of that last communication with all supporting documentation, then called them. The guy I talked to cracked up and said his client should learn how to write a letter. They stopped calling.

Funny thing is, I've later found out some of these bills were legitimate. I just couldn't put the pieces together at the time. Lots of $$$$$ in lab work from some company based in NC I didn't pay. I finally got told I needed to talk to Dr. Murtha or something like that at a clinic I'd never heard of. So I blew that one off and they went away after a while. Their burden to show I owe, not mine to show I don't! Years later cleaning out old records I figured out that Murtha was a doctor at a clinic that operated the other facility and was over everything. His name was on all the billings. These were real tests (expensive) for my wife which were delayed in billing about 2 months. All they had to do was connect the dots for me! That was about $2000 I didn't pay and got my insurance company to turn down.

The pattern of asking a billing party to demonstrate that I owe works quite well. Few companies seem to know how to do that.