We (billing department) have been told previously that if a patient presents to the office just for a lab slip, that this wasn't a billable visit as we should be able to write the lab req without seeing the patient. Recently we had an immunization clinic in which our provider saw several patients and documentation is as follows: "Seen at immunization clinic. Needs MMR/Varicella titers. Does not remember if he had chickenpox or varicella vaccine/MMR vaccine. Lab slip given for MMR/VZV titer. Assessment: Antibody immunization response- lab slip given for MMR/VZV titer- will call with results and immunize if needed." These visits were all coded as 99201 as all were new patients. Should we be billing these out as 99201/99211 depending on patient status? or is this truly a non billable service?