FEV1 MEF50 FENO Asthma control
Responders Increase≥10% predicted Increase≥15% predicted Decrease <20% for values >35 (50) ppb or <10 ppb for values <35 (50) ppb Improvement in asthma control
Non-responders Change<10% predicted Change<15% predicted Decrease ≤20% FENO ≤20% for values over 35 (50) ppb or ±10 ppb for values <35 (50) ppb or increase >20% for values >35 (50) ppb or >10 ppb for values <35 (50) ppb No changes in partial asthma control or deterioration in asthma control