[Measurement of the average diameter of the tracheal air column on chest x-ray].
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002357:Cartilage Diseases / Q000000981:diagnostic imaging; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D013902:Radiography, Thoracic; D012015:Reference Standards; D014132:Trachea / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D014133:Tracheal Diseases / Q000000981:diagnostic imaging