Which of the following is NOT a primary component of the MPDS?

The selection of "Patient History Documentation" as the answer is based on understanding the core structure of the Medical Priority Dispatch System (MPDS). The MPDS is designed to streamline the emergency medical dispatch process and includes specific protocols for effective data gathering and case management.

"Case Entry Protocol," "Case Exit Protocols," and "Diagnostic and Instructional Tools" are fundamental components of the MPDS. The Case Entry Protocol is critical for initiating contact, gathering essential information about the incident, and determining the nature and severity of the medical emergency. Case Exit Protocols are vital for concluding the interaction, ensuring that the transition from dispatch to response is smooth and that all necessary information is communicated. Diagnostic and Instructional Tools provide dispatchers with the necessary resources to assess the situation accurately and guide emergency responders effectively.

In contrast, "Patient History Documentation" does not fit as a primary component because, while it may be important in the broader context of patient care and hospital-based practices, the MPDS itself focuses on immediate dispatch protocols and decision-making as opposed to detailed historical medical records. Therefore, it is not a direct element of the MPDS structure or functionality.