Response to the article A population-based survey of the prevalence and risk factors of chronic obstructive pulmonary disease in Shanxi province (China)
1 Servicio de Neumología, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain. Electronic address: jmherper@hotmail.com.
2 Servicio de Neumología, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain.