When general practitioners (GPs) order an ambulance, their calls are handled by staff at the emergency medical dispatch centre (EMDC) who then select an appropriate response. There are currently no data evaluating this mode of communication between the GPs and the staff at the EMDC. METHODS: A retrospective study was performed based on evaluation of calls during which GPs requested a rapid response ambulance. Over a period of three months of 2014, 1,334 calls were included for evaluation according to specific parameters including a transactional analysis of the communication. RESULTS: We found problematic communication in less than 2% (n = 25) of the evaluated calls. In 68% of the 25 problematic cases transactional analysis showed that the staff at the EMDC initiated the problematic communication. In 4% (n = 51) of the calls, the GP delegated the call to a secretary or nurse, and we found that these calls were more likely to contain problematic communication (odds ratio = 5.1). In 18% (n = 236) of the cases, there was not sufficient information to assess if the physician-manned mobile emergency care unit (MECU) should have been dispatched along with the ambulance. CONCLUSIONS: Problematic communication is rare, occurring in less than 2% of the calls. Problems are more frequent when the GP delegates the call. Furthermore, we established that the communicative problems were more likely to be initiated by the staff at the EMDC than by the GP. In addition, we found that there was insufficient information to assess if the MECU should be dispatched in nearly 20% of all calls. FUNDING: none. TRIAL REGISTRATION: The study was approved by the Danish Data Protection Agency (ref. no. 2008-58-0035). Informed consent from individual patients or ethics committee approval was not required since it was a register-based study solely and no person-identifiable data were used.