The investigators reflect : What we have learned from the deepening our understanding of quality improvement in Europe (DUQuE) study - Groene, Oliver (London School of Hygiene and Tropical Medicine. Department of Health Services Research and Policy) ; Suñol Sala, Rosa (Universitat Autònoma de Barcelona. Institut Universitari Avedis Donabedian) ; Klazinga, N. (University of Amsterdam. Academic Medical Centre-AMC) ; Kringos, D.S. (University of Amsterdam. Academic Medical Centre-AMC) ; Lombarts, M.J.M.H. (University of Amsterdam. Academic Medical Centre-AMC) ; Plochg, T. (University of Amsterdam. Academic Medical Centre-AMC) ; Lopez, M. A. (Universitat Autònoma de Barcelona. Institut Universitari Avedis Donabedian) ; Secanell, M. (Universitat Autònoma de Barcelona. Institut Universitari Avedis Donabedian) ; Vallejo, P. (Universitat Autònoma de Barcelona. Institut Universitari Avedis Donabedian) ; Bartels, Paul (Central Denmark Region. The Department of Clinical Medicine. Aalborg University) ; Kristensen, S. (Central Denmark Region. Center for Healthcare Improvements. Aalborg University) ; Michel, P. (Comité de la Coordination de l'Evaluation Clinique et de la Qualité en Aquitaine) ; Saillour-Glenisson, F. (Comité de la Coordination de l'Evaluation Clinique et de la Qualité en Aquitaine) ; Vlcek, F. (Czech Accreditation Committee) ; Car, M. (Dr Foster Intelligence-DFI) ; Jones, S. (Dr Foster Intelligence-DFI) ; Klaus, E. (Dr Foster Intelligence-DFI) ; Bottaro, S. (European Hospital and Healthcare Federation-HOPE) ; Garel, Pascal (European Hospital and Healthcare Federation-HOPE) ; Saluvan, M. (Hacettepe University) ; Bruneau, Charles (Haute Autorité de la Santé-HAS) ; Depaigne-Loth, A. (Haute Autorité de la Santé-HAS) ; Shaw, C. (University of New SouthWales) ; Hammer, A. (Institute for Medical Sociology. Health Services Research and Rehabilitation Science. University of Cologne-IMVR) ; Ommen, O. (Institute for Medical Sociology. Health Services Research and Rehabilitation Science. University of Cologne-IMVR) ; Pfaff, H. (Institute for Medical Sociology. Health Services Research and Rehabilitation Science. University of Cologne-IMVR) ; Botje, Daan (Netherlands Institute for Health Services Research (NIVEL)) ; Wagner, Cordula (Netherlands Institute for Health Services Research (NIVEL)) ; Kutaj-Wasikowska, H. (Polish Society for Quality Promotion in Health Care-TPJ) ; Kutryba, B. (Polish Society for Quality Promotion in Health Care-TPJ) ; Escoval, A. (Portuguese Association for Hospital Development-APDH) ; Lívio, A. (Portuguese Association for Hospital Development-APDH) ; Eiras, M. (Portuguese Society for Quality in Health Care-SPQS) ; Franca, M. (Portuguese Society for Quality in Health Care-SPQS) ; Leite, I. (Portuguese Society for Quality in Health Care-SPQS) ; Almeman, F. (Turkish Society for Quality Improvement in Healthcare-SKID) ; Kus, H. (Turkish Society for Quality Improvement in Healthcare-SKID) ; Ozturk, K. (Turkish Society for Quality Improvement in Healthcare-SKID) ; Mannion, Russell (University of Birmingham) ; Arah, Onyebuchi A (University of California. Los Angeles-UCLA) ; Dersarkissian, Maral (University of California. Los Angeles-UCLA) ; Thompson, C.A. (University of California. Los Angeles-UCLA) ; Wang, A. (University of California. Los Angeles-UCLA) ; Thompson, A. (University of Edinburgh)