TABLE 1.

CHARACTERISTICS OF DATA INCLUDED IN ANALYSIS, WHICH WERE RESTRICTED TO NON-HISPANIC WHITE SUBJECTS

First Author (Reference)	Country	No. in Study	Non-Hispanic White Subjects Included in Analysis	Age Range (yr)	Population Selection	Exclusion Criteria	Equipment
Hankinson (2) NHANES III	U.S.	20,627	2,273	8–80	Random sample of the U.S. population living in households	Symptomatic, history of smoking, <2 acceptable maneuvers	Dry rolling seal spirometer
Rosenthal (7)	U.K.	1,007	761	4–19	12 London schools	Acute respiratory illness in the 3 wk before testing, or symptoms suggesting chronic respiratory disease	12-L dry rolling seal spirometer (OHIO 840)
Lebecque (12)	Belgium	377	316	5–18	Children in private schools from upper-middle-class families	Prior history of wheezing or use of bronchodilator, chronic cough, exercise intolerance, frequent or severe upper respiratory tract infections, use of tobacco products, major health problems (particularly cardiac or thoracic surgery), asthma of parents or siblings, or a history of respiratory infection during the month before the study	Automated 8-L water sealed spirometer (Eagle 1)
Corey (13)	Canada	337	248	5–19	Not specified	Lung disease	Wedge spirometer