Final answer:
The medical office should notify the affected patients first following a breach of patient information, then the Department of Health and Human Services if more than 500 individuals are affected, and subsequently the Office of Civil Rights.
Step-by-step explanation:
When a medical office experiences a breach of patient information involving 200 patients, it is important to know which entity should be notified first regarding the breach. According to the Health Insurance Portability and Accountability Act (HIPAA), the medical office should notify the affected patients without unreasonable delay and in no case later than 60 days following the discovery of the breach. If the breach affects more than 500 individuals, the Department of Health and Human Services (DHHS) must also be notified without unreasonable delay, but no later than 60 days after the discovery of the breach. Following that, the Office of Civil Rights (OCR), which enforces HIPAA compliance, should also be notified. It's not specifically required to notify the Center for Medicare and Medicaid Services (CMS) solely because some of the patients are Medicare beneficiaries, unless CMS is the breached entity or has a specific requirement due to the breach.