In Emergency Departments (ED) in Denmark and internationally, triage manuals are used to divide incoming patients according to their acute clinical severity, and thus assess who should be examined and treated first. However, the triage manuals are criticized for being imprecise in the intermediate categories. Furthermore, the triage manuals, nationally and internationally, are criticized for not adequately involving the patient's perspective and context. In addition, triage is not independent of personal factors and workload, which may contribute to interprofessional variation. Further, patients themselves express a desire to be even more involved. Also, the relationship between patient and healthcare professional has a direct impact on the quality of health services, however, there are divergent perceptions of what patient involvement entails. Patient-Reported Outcome (PRO) data is one way in which patient involvement can occur. PRO is data reported directly from the patient without interference from the healthcare professional and is thus self-reported data, typically generated through survey studies among patients. A strength of PRO data is that these are often more sensitive which may, for example, demonstrate a higher degree of severity of the patient's symptoms. Furthermore, it is considered a strength that PRO data can be used at both group level, for example in quality assurance, as well as at an individual level to support the decision making of healthcare professionals and thereby ensure efficient use of resources. Due to lack of evidence-based knowledge in the field and despite the potential of using PRO data, the information of patients and / or relatives is not used systematically in the Emergency Department. This also applies in the acute contact, where an imprecise initial evaluation of the patient's overall medical needs can cause both over- and under-triaging to the detriment of the overall patient course. The result is an inappropriate allocation of resources at the organizational level and a poorer quality in the treatment process. This points to the need to use relevant patient-reported measures (PROM), the tool for measuring PROs. One such instrument is Degree-of-Worry (DOW), which measures the patient's self-reported level of worry. DOW is a ten-point score of self-reported worry (from 1 = minimal concern to 10 = maximally concerned), reflecting the patient's own assessment of acute illness and own perception of concern. DOW has been scientifically tested in connection with telephone triage at the medical helpline 1813 (MH1813) as a five-point score. The patient's DOW, measured at the time the patient makes his first call to the MH1813, is strongly associated with the probability of acute hospitalization within 48 hours. However, a pilot test with DOW as a five-point score in the Emergency Department indicates a ceiling effect, by which DOW will be presented as a 10-point score in this setting. DOW has the potential to increase patient safety, create greater patient involvement and increase efficiency so that the lengths of stay reflects the triage level. A previous study suggests that DOW could also be used advantageously in other similar settings, such as Emergency Department, which, however, requires that potential implementation barriers is examined.