Table. 2—

Exhaled NO at multiple expiratory flows measurements at different exhalation flows in the groups of subjects studied

ICCPooled sd1NonsmokersSmokers-GOLD0GOLD1–2GOLD3–4
Subjects n18301815
eNO expiratory rate mL·s–1
 100.977**0.84±1.543.5±7.3 (39.8–47.1)28.1±13.4 (23.1–33.1)33.2±22.1 (22.2–42.2)31.1±10.8 (25.1–37.1)
 500.993**0.30±0.3613.5±2.4 (12.2–14.6)10.1±4.3 (8.3–11)14.6±7.3 (10.9–18.2)15.2±5.7 (12.0–18.4)
 1000.992**0.18±0.198.0±1.3 (7.4–8.6)6.5±2.4 (5.5–7.4)9.1±3.8 (7.2–11.1)9.2±2.6 (7.6–10.5)
 2000.989**0.12±0.135.2±0.7 (4.8–5.5)4.7±1.2 (4.1–5.2)6.6±2.1 (5.6–7.7)6.7±1.6 (5.8–7.5)
 2600.988**0.11±0.134.1±0.6 (3.8–4.4)3.9±1.1 (3.4–4.3)5.6±1.6 (4.8–6.4)5.8±1.3 (5.0–6.4)
Pooled sd1,total#0.32±0.60
  • Data are presented as mean±sd (95% confidence intervals). ICC: intra-class correlation coefficient on each flow in all subjects (Pearson correlation coefficient); pooled sd1: pooled sd on each flow in all subjects; GOLD: Global Initiative for Chronic Obstructive Lung Disease; eNO: exhaled nitric oxide; pooled sd1,total: pooled sd for total 360 observations (eNO of 72 subjects×5 exhalation flows = 360). **: p<0.01 versus pooled sd1,total±sd.#: n = 405.