We thank D. Rawlings and colleagues for their highly relevant question. Our study 1 was performed to compare high-resolution computed tomography (HRCT) with lung function in the assessment of disease progression in cystic fibrosis (CF). It was beyond the scope of this paper to evaluate the complex question of radiation risk versus clinicalbenefit of HRCT in these patients. Determining the risk–benefit profile of HRCT in CF patients is currently a research topic of high priority in our group. At this time, we believe that the use of HRCT in CF patients is consistent withthe 1997 European …