Which protocol is primarily used by EMDs to assess emergencies?

The Medical Priority Dispatch System (MPDS) is specifically designed for Emergency Medical Dispatchers (EMDs) to systematically assess medical emergencies. This protocol utilizes a structured, systematic approach to ensure that EMDs can efficiently determine the nature and urgency of a medical situation. The MPDS provides a set of standardized questions and protocols tailored to gather critical information from callers, leading to appropriate prioritization for dispatching emergency services.

The MPDS also helps EMDs to provide pre-arrival instructions, which can be vital in managing a patient's condition before responders arrive on scene. This is not just about assigning priorities; it’s also about ensuring the safety and wellbeing of the patient through informed guidance during emergencies.

In contrast, other options listed may imply systems or protocols relevant to emergency calls or responses, but they do not specifically focus on the assessment of medical emergencies by EMDs like the MPDS does. This strong emphasis on structured assessment and response prioritization makes the MPDS the correct choice for this question.