Just went through this scenario with our lab's billing. We provided education and LCD information as a base guideline to our ordering providers, who are internally changing their drug screening processes to support medical necessity requirements in their own patient records. The rules these insurances are adopting by restricting the number of drug classes tested, is to move away from the trend of "blanket" ordering for every patient of the pain management practice, etc. ordered the same full panel repeatedly throughout treatment, regardless of whether the patient reported or didn't report use of additional substances or illicit.
Basically the rule is to force the provider to order less tests, and a more customized test to the patient's background and drug history. Particularly if they have more than one test in a calendar year. If the first test, is a "blanket" full panel for the threshold testing, and the results are all negative, the insurance expects that if the patient reports a negative use history at the next screen and trusts the patient based on history, symptoms, dx, etc, the provider should not order the SAME full panel, but rather a custom panel of drug classes that MAY reflect a positive result, or order presumptively, or no test at all. (Medicaid started this trend, followed by 3rd Party Medicare payors focusing on individual dx codes, and now the commercials are capping as well)
It is assigning more responsibility on the provider and the treatment protocol/program, and making medically necessity over a longer period of patient history, harder and harder to document. Your providers documentation would need to be airtight to explain why all 15+ drug classes need to be ordered each time for that particular patient. Its rare, in my experience, that a patient sample has a positive or inconsistent result for more than 5 drug classes show on a sample at one time... Makes you wonder how a patient would even function or be living considering some of the fatal consequences of mixing multiple drugs and illicit at one time.
Our providers are now ordering customized panels for long term patients that would fit into the G0480/481 description after the initial test, and we are not having any issues getting paid as an OON lab, as long as the DX codes support the medical necessity as well.