CFTR and interstitial lung disease: This technology has already been applied to diaphragm motion analysis in healthy volunteers,21 suspected diaphragm palsy,22 chronic obstructive pulmonary disease23 24 and individuals taking CF transmembrane conductance regulator (CFTR)-modifying drugs.25 PLA has been shown to correlate well with vital capacity in healthy volunteers26 and those with interstitial lung disease,27 but to our knowledge, this relationship has not been explored in pwCF.