Discussion Because a quick response to emergency calls for patients in a life-threatening conditions is important to improve their survival rate [16], several countries have introduced a priority dispatch system for ambulances [17-24]. On October 1st, 2008, Yokohama, Japan started a

new emergency medical service system that was designed to dispatch ample emergency staff quickly to patients in Inhibitors,research,lifescience,medical a critical condition. The present study aimed to assess the algorithm, which had originally been constructed based on data collected previously from 4,301 cases, prior to the start of the new system [14]. In the new Yokohama system, when the life threat risk as estimated by the logistic model is higher than 10%, the emergency call is categorized as A+. Category A+ targets patients that face a strong possibility of dying. The Emergency Medical Division of the Yokohama Safety Management Bureau reported that under the new emergency system, the mean arrival time of the first responder to the scene for patients categorized as A+ at the moment of the emergency call was approximately one minute Inhibitors,research,lifescience,medical shorter than that for other patients. Whether the new system improved survival rate from CPA should be evaluated in further studies. Logistic models were applied to construct an algorithm to assess the life threat risk

from the information received in calls to emergency services. The algorithm Inhibitors,research,lifescience,medical for assessing the life threat risk was constructed according to the type of caller. This is based on a concept that the weight of data obtained from the calls is likely to differ depending on the type of caller. For instance, a call reporting that a patient cannot walk could have different implications when made by nursing home staff compared Inhibitors,research,lifescience,medical to other types of callers. The life threat risk was estimated synthetically, from observable signs selleck products provided by callers to the ambulance system. The model allowed explanatory variables to be recorded as unknown or unconfirmed. This is based on a concept

that information that is unknown Inhibitors,research,lifescience,medical or unconfirmed is potentially related to the severity of patient’s condition and can be used as a factor in the risk assessment. In the triage program, the patients’ life threat risk was expressed as a percentage. For example, when a call was made by a family member who was in panic, if the patient’s age was 70 years, consciousness not clear and breathing status abnormal, if the patient was lying down and unable to walk, the patients face cyanotic, and Mannose-binding protein-associated serine protease sweating unable to be confirmed, then the life threat risk was estimated to be 19.2% by the model. In the Yokohama New Emergency System, patients were categorized as potentially life threatened when the estimated life threat risk was higher than 10%. The cut-off value was determined prior to the start of the system according to the city’s capability of dispatching ample staff, i.e., from a viewpoint on the amount of acceptable false positives, such as overtriage.