3Elias Hernandez MT, Ortega Ruiz F, Sanchez Riera H, et al, Role of dyspnea in quality of life of the patient with chronic obstructive pulmonary disease, Arch Bronconeumol, 1999, 35 : 261 -266.
4Schlecht NF, Schwartzman K, Bourbeau J, Dyspnea as clinical indicator in patients with chronic obstructive pulmonary disease, Chron Respir Dis, 2005, 2(4) : 183 -191.
5Hajiro T, Nishimura K, Tsukino M, et al, A comparison of the level of dyspnea vs disease severity in indicating the health-related quality of life of patients with COPD, Chest, 1999, 116: 1632-1637.
6Engstrom CP, Persson LO, Larsson S, et al, Functional status and well being in chronic obstructive pulmonary disease with regard to clinical parameters and smoking: a descriptive and comparative study. Thorax, 1996, 51:825 -830.
7Jone PW, Quality of life measurement for patients with disease of the airflows, Thorax, 1991,46:676-682.
8Seemungal TA, Donaldson GC, Paul EA, et al, Effect of exacerbation on quality of life in patients with chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 1998, 157(5 Pt 1) : 1418 -22.
9Miravitlles M, Ferrer M, Pont A, Zalacain R, et al. Effect of exacerbations on quality of life in patients with chronic obstructive pulmonary disease: a 2 year follow up study. Thorax, 2004, 59(5) : 387 -395.
10Doll H, Grey-Amante P, Duprat-Lomon I, et al. Quality of life in acute exacerbation of chronic bronchitis : results from a German population study. Respir Med, 2002, 96(1 ): 39-51.
10Zhong NS, Wang C, Yao WZ, et al. Prevalence of chronic ob- structive pulmonary disease in China [J]. Am J Respir Crit Care Med, 2007, 176(8): 753-760.
