We just went thru a Cert review for oxygen and were denied stating "documentation submitted was not sufficient to support medical necessity. It is a recommendation that suppliers obtain and review the appropriate medical records and maintain a copy in the beneficiary's file prior to filing the claim." I called the cert coordinator to ask why and she said that the physician's medical records need to state that the patient is benefiting from the home oxygen therapy and must also document what is stated on the cmn. I am wondering what is the process other supplier's have to prevent these denials. We are assuming the doctor is documenting in their records since they signed the cmn. Noridian is in the process of recouping the payment we rec"d for the claim that was reviewed. I'm wondering, are they going to recoup all payments for all the previous claims billed for oxygen? Any suggestions?