The aim of Emergency Medical Dispatch (EMD) is to ensure prompt access to medical care for all at all times, initiate appropriate responses quickly, arrange suitable hospital facilities, and coordinate patient transport and hospitalization. In France, care begins with an incoming call managed by the EM Dispatchers, who collect the patient's details and assess the seriousness of the situation. This severity assessment is essential for triggering the appropriate resources: direct dispatch of first-aiders in extreme emergencies, or transfer of the call to an emergency or general practitioner. Under- or over-assessment will necessitate redirection, resulting in a loss of time and opportunity for the patient, or emergency channel congestion. Errors at this stage can impact the entire care pathway. To assist EM dispatchers, aids have been developed. Firstly, In France, a diploma course was created in 2019. Various training methods exist. Their contribution to the quality of incoming calls handling remains unevaluated. Secondly, EM centers use regulation protocols designed to guide dispatchers in call handling and identifying the seriousness of the situation. The regulation protocol used at Besançon University Hospital is ProQA (Priority Dispatch Corporation, Salt Lake City, UT, US). It uses standardized questions and records EM Dispatchers' decisions and the responses they obtain from callers. These responses are considered by ProQA, which then assigns a severity code to the call. The assistance provided by regulation protocols, however useful, remains insufficient. Contextual factors can complicate compliance with regulation protocols, making matching resources to needs challenging. AQUA is a software package dedicated to quality control, enabling EM Dispatcher's supervisors to rate the quality of all stages of the call-taking process. This ensures that all key questions have been asked and that they have been asked correctly. In addition, the 'severity' code obtained by the EM Dispatcher can be compared with the 'severity' code obtained by the supervisor, using a qualifying analysis method and data entry software. The calls are replayed under optimal conditions, in a calm environment and allowing supervisors to listen multiple times to ensure no information is missed. the supervisors' code is therefore the reference code. CRRAQPA study's aim is to assess the quality of incoming call handling and to identify the factors that influence this quality.