FEV1 ≥ 60 (Total Number = 337)

Pass

Fail

NHANES III (1999)

332 (98.51%)

5 (1.48%)

Crapo et al. 1981

330 (97.92%)

7 (2.07%)

Knudson et al. 1983

331 (98.21%)

6 (1.78%)