Fluctuation-based clustering reveals phenotypes of patients with different asthma severity

This prospective observational cohort study examined whether serial PEF measurements could identify disease phenotypes in 120 children with a range of asthma severities. Pulmonary function endpoints included FEV1, FVC, FEV1/FVC ratio, and FEF25–75, and were measured using a Vitalograph spirometer. FeNO was measured using the NIOX VERO device.