Assessing COPD patients' experiences of physical activity: From qualitative interviews to item generation
Fabienne Dobbels, Ellen Drost, Janneke Elberse, Chrysa Feridou, Corina De Jong, Laura Jacobs, Anja Frei, Milo Puhan, Pim De Boer, Thys Van der Molen, Kate Williams, Hilary Pinnock, Thierry Troosters, Niklas Karlsson, Karoly Kulich, Katja Rudell
European Respiratory Journal Sep 2011, 38 (Suppl 55) p292;