According to definition, chronic wounds do not show any tendency for healing over months. From the socio-economic perspective they are of great importance due to their frequency, patient burden and costs for the health system. In wound care, medical devices play a crucial, even more important role than drugs as nearly every wound needs at least a dressing. A wound passes through several phases of wound healing, which often demand different therapies and differentiated wound dressings in the sense of a "phase-adapted" wound therapy. "Modern wound care" reflects a cross-sectoral, interdisciplinary and interprofessional approach founded on evidence-based and quality-assured procedures according to the most recent medical knowledge. Clinical research on chronic wounds is characterised by a great variety of wound types and conditions, the strong impact of pathogenetic factors and complications, a multifaceted, frequently still manual therapy and long periods of healing. In many instances, several treatments are applied intermediately in the same patient, which serve different purposes and thus require different study endpoints. An analysis of the European Wound Management Association (EWMA) revealed that, on an international level, only few of the published clinical trials on chronic wounds meet the basic quality requirements. Accordingly, it is the objective to establish national and international consensus on standards of the methodology and interpretation of wound outcomes, such as the most recent EWMA activities and the German national consensus conference started in 2012. EXAMPLE OF A HIGH-QUALITY CLINICAL WOUND STUDY: As an example of a high quality randomised study on chronic wounds, hyperbaric oxygen treatment (HBOT) was evaluated as adjuvant treatment for diabetic foot ulcers compared to placebo (Löndahl et al., 2010). This trial is characterised by a diligent study design, a substantiated study rationale and an independent steering committee. Precise and reliable definitions for the end points were selected, their evaluation performed in a double-blinded manner, and the ITT and PP analyses were described transparently. Outcomes included both clinical and patient-reported parameters. Reporting according to the consort criteria revealed a significantly higher healing rate in the HBOT group. Chronic wound therapy is a complex intervention with highly variable clinical conditions. Parts of missing quality and validity in therapeutic studies on chronic wounds, however, might be improved without noteworthy efforts if existing guidance is followed. This includes the motto: "better fewer but better conducted studies". Clinical research should focus on key principles and products, and it should prioritise research questions. Research on central principles of action in wound products between companies could further increase global research efficiency.

Augustin, , , , , , , , (2012). [Examples of practice: clinical trials for medical devices and their application: wound care]. Zeitschrift fur Evidenz, Fortbildung und Qualitat im Gesundheitswesen, 2012 ;106(5):347-53; discussion 353. https://www.ncbi.nlm.nih.gov/pubmed/22818157