A total of 252 patients diagnosed as having asthma by medical specialists (certified by either the Japanese Respiratory Society or the Japanese Allergology Society) participated in this prospective, observational study to investigate the correlations between symptoms and eosinophilic airway inflammation. All patients with asthma were enrolled consecutively, without any selection. After giving their written, informed consent, the patients answered two kinds of questionnaire: the modified F scale and the G scale (Table 1). In developing the G scale, the intention was not to use it for the diagnosis of asthma or rhinosinusitis. The goal was to evaluate chronic rhinosinusitis; but symptoms of acute rhinosinusitis and those of chronic rhinosinusitis cannot be distinguished using the G scale. Complications associated with asthma, such as rhinosinusitis, GERD, or dyspepsia, were not diagnosed by objective findings in all patients in the present study, although some patients were diagnosed, based on the findings of endoscopy or computerized tomography (CT), as part of their routine medical care. FeNO was measured in all participants, using the NIOX MINO® (Aerocrine AB, Solna, Sweden), according to the manufacturer’s instructions.