Ghezzi M, et al. - Whether structured light plethysmography (SLP) is feasible in children with asthma, was investigated among patients with asthma exacerbation (group 1), with well-controlled asthma (group 2), and healthy controls (group 3). SLP evaluation and a lung function test was performed on every patient. SLP evaluations for group 1 vs groups 2 and 3 revealed a statistically significant increase in the ratio of inspiratory flow at 50% of tidal volume (Vt) to expiratory flow at 50% of Vt, in which Vt was taken to be the exhaled chest wall movement, and flow was taken to be the time derivative of the chest wall movement (IE50) value; the data were consistent with the spirometry parameter. Additionally, data demonstrated a correlation between the IE50 and forced expiratory volume in the first second of expiration.