Which factor needs to be identified during a breach investigation regarding PHI faxed to an unauthorized person?

Identifying the unauthorized person who received the protected health information (PHI) is crucial during a breach investigation as it directly relates to the security and privacy incident's impact. Understanding who received the PHI can guide the response and mitigation strategies, including notifying affected individuals and relevant authorities as required by laws such as HIPAA. This identification helps the organization understand the breach's scope—the potential risk of identity theft or further dissemination of the information. Additionally, it can inform the necessary legal and compliance steps, including any required reporting to regulatory bodies.

Considering the other factors, while the identity of the PHI owner, the extent of the disclosure, and the method of transmission are all important to the investigation, they do not specifically address who constitutes the unauthorized recipient. The urgency of notifying both the affected parties and regulatory bodies hinges significantly on knowing the recipient's identity and their capability or intent concerning the disclosed information.