Choosing, Changing, and Adding Diagnoses: Are These
Audit Triggers?
By Barbara Griswold, LMFT (July 12,2022)

“Barbara, I suck at diagnosis. Will a health plan question my diagnosis?” I suck at diagnosis also. Most of us never received much training in clinical diagnoses. We hate how assigning a diagnosis pathologizes our clients. And I think we can all agree that the DSM is pretty messed up, and doesn’t reflect the issues we see in therapy. The good news is that insurance plans aren’t likely to argue with your diagnosis. They know that 10 different therapists might give 10 different diagnoses for the same case. So don’t sweat diagnosis too much. In your notes or in a clinical review, they will focus more on whether medical necessity for treatment exists — that is, whether the work you are doing is aimed at reducing the symptoms of the diagnosis you give.
“How soon do we have to give a diagnosis?” If you are billing insurance for the first session, you will need to assign a diagnosis for the claim. If you are unsure about the diagnosis, it is fine to put down your best guess, or you could wait to submit the bill until a second session when you have had more time to assess. Remember, however — to bill insurance, the client will usually need to have more than a DSM-5 Z-code (though check– a few insurance plans reimburse for Z-codes).
“What if later in treatment I feel my original diagnosis was wrong, or I need to add a diagnosis? Will this trigger an audit?” I hear this question a lot. I’m not sure where we got the idea that whatever diagnosis after the first session is cast in stone. Diagnoses are expected to reflect your best understanding at the time you assign them. As more information is gathered, it is expected that your diagnosis might change. Also, the client’s condition may change — for example, from Major Depression, Severe, to Major Depression, Moderate — and your diagnosis should change to reflect this. Or you may have given an Adjustment Disorder at the beginning, but with time you see the client has a more serious Anxiety or Depressive Disorder underlying it.
“If I have two diagnoses, should I just put one on the claim form?” No. Withholding diagnoses means you are not giving the health plan the full and accurate clinical picture, which could be considered insurance fraud. All diagnoses must be included.
“If I change my original diagnosis, must I document this?” Yes. In the client chart or progress notes, you should document that you have changed the diagnosis, and explain your decision. You might also consider whether you need to alter your treatment plan to reflect a new goal around the new diagnosis. (For more on treatment plans, check out my webinar “How to Write a 10-Minute Treatment Plan”)
“Would it ever seem suspicious if I change my diagnosis?” Well, maybe if they’ve called you for a Clinical Review and suddenly you change a diagnosis. 🙂
“How often should I revisit my diagnosis in treatment?” I’d say make it a habit to review and update all your diagnoses at least every 3-6 months. Too often we assign a diagnosis and then don’t update it — EVER. And then we are called for a clinical review, and we feel forced to explain an out-of-date diagnosis.
“If I reevaluate a diagnosis with a client in the middle of treatment, can I bill that session as a diagnostic assessment (CPT 90791)?” While the health plan might pay for it, I wouldn’t want to defend that in an audit. 90791 generally requires a history-taking that probably wouldn’t exist mid-treatment.