The relationship between coal mining and chronic nonspecific respiratory disease.
D000328:Adult; D002908:Chronic Disease / Q000209:etiology; D003032:Coal Mining; D004493:Education; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011009:Pneumoconiosis / Q000209:etiology; D012140:Respiratory Tract Diseases / Q000209:etiology*; D012924:Social Conditions; D014903:West Virginia