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Certificate of Medical Necessity (CMN) Tips

Having a physician complete a CMN involves several steps. A CMN consists of four sections, A, B, C, and D. Sections A and C are to be completed by the supplier and then sent on to the physician, who answers the questions in Section B and signs and dates the attestation statement in Section D. It is important that the sections you are required to fill out are completed before you send the CMN to the doctor. Otherwise, the doctor will not know what exactly was given to the patient. It is also important for you to check over the doctor's sections once you receive it back. Someone in the physician's office can answer the questions (a nurse or other clinician, but not the supplier), but the physician must sign the CMN. Once the CMN is complete, the item(s) may be billed to Medicare.

Some common problems with CMN's are:

• No initial date - this must be the date that the item is needed (supplier responsibility)
• Missing height or weight, especially with nutrients and special wheelchairs (supplier responsibility)
• No length of need - only the physician can enter this
• No diagnosis codes - only the physician can enter these
• Answers changed - i.e. cross outs - if the doctor makes an error, he needs to correct his answer and sign his initials and the date next to the change or the CMN will be invalid
• Not enough detail in Section C - you must make sure to have a description of the equipment, the quantity, the amount that you are charging (monthly, if it is a rental) and Medicare's fee schedule for the item (you may use N/A if it is a by report item) (supplier responsibility)
• Doctor's signature missing - the CMN is not valid until the physician signs it

If you are transmitting your claim electronically, you may use your software program to enter the information from the CMN exactly as it is written on paper. Then, you may transmit the CMN with the initial month. If you are sending your claim on paper, you must include a copy of the original CMN (just the front) with your first month. It is suggested that you should only send the first month when you are submitting the CMN to prevent any denials before the CMN is entered into the system. Also, try not to send a copy of the CMN with every month; it causes confusion, and once the DMERC receives the first one, it will be entered into the CWF and remain there for future reference.

You must also make sure to keep track of the number of months for which the item is prescribed. If the doctor indicates that the length of need is only 12 months, you will require a new or revised CMN to bill for any longer than that. Medicare keeps the length of need in their system and will begin denying your claims if you bill for longer than the original length of need.

The original CMN must remain in your files and Medicare may audit you at any time. If the information on the original CMN does not match what was submitted to the DMERC, you may be responsible for refunds of any monies paid to you and also, if you are billing electronically, you may have your electronic billing ID suspended.

You are allowed to attach a cover letter to physicians when you send them CMN's; just be careful what you say in them. You may include things such as explanations of what to fill out, where they should send the CMN's, and direct quotes from Medicare's policy. Be sure not to tell doctors how to answer questions or what to use as a diagnosis. Remember that it is the physician's duty (not the supplier's) to prescribe the equipment and verify the medical necessity for it.

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