We have a CLIA waived certificate. An outside lab performs test 86003, but does not bill any insurance. The lab bills us, and we bill the patient's insurance.
We billed Medicare, but are getting denied. Originally denied for incorrect # of units billed. Most recently denied for CO-B7 with N570. Patient did sign an ABN, a modifier GA was submitted. We did not use a QW modifier. All other insurances are paying us.
Can we not bill and get reimbursed from Medicare, and if not, why?
Can we still bill patient as we have a signed ABN even though it denied for a CO?