Supporting the diagnosis of non-specific respiratory symptoms in primary care: the role of exhaled nitric oxide measurement and spirometry.

Aims: To assess whether exhaled nitric oxide (FENO) measurements improve management and clinician confidence in patients presenting with non-specific respiratory symptoms.

Methods: This observational study was based in a large primary care practice (15,500 patients, 14 GPs). Patients had non-specific respiratory symptoms for at least six weeks.