Comparison of difference in LCI (LCI<sub>N2</sub>−LCI<sub>SF6</sub>) to FEV<sub>1</sub> (% predicted). JensenRenee StanojevicSanja GibneyKaryn Giraldo SalazarJuliana GustafssonPer SubbaraoPadmaja RatjenFelix 2013 <p>Healthy controls are represented by the open circles and subjects with CF by the solid circles. The difference in LCI was greater as FEV<sub>1</sub> became lower such that on average LCI<sub>N2</sub> was disproportionately higher than LCI<sub>SF6</sub> in subjects with abnormal spirometric findings.</p>