Evidence and Evidence Gaps - an Introduction]

Background: Treating patients requires the inclusion of existing evidence in any health care decision, to be able to choose the best diagnosis or treatment measure or to make valid prognosis statements for a particular patient in consideration of the physician's own expertise. The basis are clinical trials, the results of which are ideally gathered in systematic reviews, rated, summarized and published. In addition to the GCP (Good Clinical Practice)-compliant planning, conducting and analysis of clinical studies it is essential, that all study results are made publicly available, in order to avoid publication bias. This includes the public registration of planned and discontinued trials. History: In the last 25 years, the evidence-based medicine (EbM) has increasingly found its way into clinical practice and research. Here EbM is closely associated with the names Archibald Cochrane and David Sackett. In Germany, both the German Cochrane Centre (DCZ) and the network of evidence-based medicine (DNEbM) were established approximately 15 years ago. In the international Cochrane Collaboration clinicians and other scientists like statisticians interdisciplinary work side by side to develop the methods of evidence-based medicine and to address the topics of evidence generation and processing as well as the transfer of knowledge. Challenge: Existing evidence primarily serves doctors to support their decision-making, but is also the basis for providing scientific proof for a health care intervention's benefit to patients and ultimately payers/health insurances. The closure of existing evidence gaps requires substantial human and financial resources, a complex organizational structure and can only succeed with the involvement of clinical and methodological expertise and specific knowledge in the field of clinical research. In addition, the knowledge must be transferred into practice, using journals, guidelines, conferences, databases, information portals with processed evidence and not least the medical education of students. One problem is the wealth of information, so that in clinical practice there may be gaps in knowledge of actual evidence. Usually it still takes several years until new knowledge is fully implemented in daily practice. Objectives: The German Society of Otolaryngology, Head and Neck Surgery (DGHNOKHC) and the German professional association of otolaryngologists (BVHNO) have a vested interest in supporting their members in the generation, processing and dissemination of evidence, and to foster the transfer of knowledge into practice. This includes the areas of diagnosis, treatment, prognosis and prevention as well as drug therapies or the application of medical devices or surgical procedures. Crucial is the regular determination of existing evidence gaps, including in the area of already established procedures, which must be followed by a prioritization of research questions and subsequent conduct of clinical research. Only with combined efforts even large trials can be performed, to test therapies and diagnostics for example, also after approval under everyday conditions. Methods, Results and Vision: The executive committees of DGHNOKHC and BVHNO have together founded the German Clinical Trials Unit for Ear, Nose and Throat medicine, Head and Neck Surgery (DSZ-HNO) to assist their members in the identification of evidence gaps and the planning and conduct of systematic reviews and clinical trials. The first projects have been started, including a BMBF(German Ministry for education and research)-funded clinical trial for the treatment of sudden hearing loss and a survey to detect evidence gaps in Otolaryngology. It seems both reasonable and feasible to provide a structure such as a jointly-run study center for doctors in hospitals and medical practices to assist in clinical research and to anchor the principles of evidence-based medicine in daily life.