Figure 5  The relationship between upper abdominal symptoms and FeNO.
Notes: (A) Spearman’s rank correlation coefficient (ρ) is −0.148 between upper abdominal symptoms and FeNO (P=0.02); (C) ρ=−0.176 between dyspepsia and FeNO (P=0.005). (B) GERD score tends to be negatively correlated with FeNO (ρ=−0.106, P=0.097).
Abbreviations: FeNO, fractional exhaled nitric oxide; ppb, parts per billion; GERD, gastroesophageal reflux disease.