Rhinosinusitis

• bitop AG — Witten, North Rhine-Westphalia, Germany

• University Hospital Ghent — Ghent, Belgium
• Univ.-HNO-Klinik, St. Elisabeth Hospital — Bochum, Germany

• Asociación Colaboración Cochrane Iberoamericana — Barcelona, Spain

• North Valley ENT — Phoenix, Arizona, United States
• Willamette ENT and Facial Plastic Surgery — Salem, Oregon, United States
• Medical University of South Carolina — Charleston, South Carolina, United States
• Alamo ENT and Associates — San Antonio, Texas, United States

• Vanderbilt University Medical Center — Nashville, Tennessee, United States

Not specified

• Fundació Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau — Barcelona, Spain

• University of Alabama at Birmingham — Birmingham, Alabama, United States

• Universitäts-Kinderklinik — Tübingen, Baden-Würtemberg, Germany
• Mukoviszidosezentrum der Friedrich-Schiller-Universität — Jena, Thuringia, Germany

• University of Calgary — Calgary, Alberta, Canada