Psychiatry Coding & Reimbursement Alert

Question: If our clinician has performed more than one evaluation of the patient over a period of time and newer observations have been uncovered during the subsequent evaluations, should the initial diagnosis be maintained as a primary diagnosis throughout? Can it be changed?

Missouri Subscriber

Answer: Typically, you will report 90791 (Psychiatric diagnostic evaluation) or 90792 (Psychiatric diagnostic evaluation with medical services) when your clinician performs an initial diagnosis of the patient. If you are reporting either of these codes, it can be reported only once on one calendar date irrespective of the time your clinician spends with the patient during the evaluation.

The diagnosis that your clinician reports after evaluation of the patient will help you choose the primary diagnosis code associated with that evaluation. You report this diagnosis with an appropriate ICD-9 (or ICD-10 code when it is launched) code. You will have to report the same diagnosis code as long as your clinician treats the patient for that particular condition. But, if your clinician finds some changes in mental status or certain new signs and symptoms that prompt him to evaluate the patient again, you can report this new evaluation with another unit of 90791 or 90792 depending on the level of evaluation performed.

During the course of evaluation, if your clinician uncovers any information or changes that prompt him to zero in on a different diagnosis than what was originally chosen as the primary diagnosis, you can report this new diagnosis as primary with an appropriate ICD-9 (or ICD-10) code instead of the code that you chose to report earlier, which may become a secondary diagnosis at that point. In other words, given the information uncovered, this new diagnosis can become the primary diagnosis code that you can use to support medical necessity of any treatment or service that your clinician provides to the patient.

In summary, the primary diagnosis listed with a particular service should always reflect the primary reason for that service on the date in question. The primary diagnosis can change over time.