Epidemiology of chronic non-specific respiratory diseases

The current state of research into the epidemiology of chronic non-specific respiratory diseases (CNSRD) is reviewed. Recommendations are made on the definitions of CNSRD for use in epidemiological studies, and various aspects of the etiology and natural history of CNSRD are identified as requiring further investigation. The need for standardization of investigative methods is emphasized. Since smoking is such an important factor in the etiology of CNSRD, it is recommended that efforts be made to discourage children from taking up the habit.