We appreciate Drs Nobre's and Thomas' thoughtful comments and further analysis of the importance of diagnostic accuracy for pulmonary embolism (PE). We very much agree that subsegmental PE presents diagnostic and management challenges. The data presented by Hutchinson et al are provocative and concerning, and the writers are correct in pointing out that false positivity could be added to the limitations of our analysis. As we discuss, our analysis has limitations because of the administrative data available in the Nationwide Inpatient Sample. Patients were identified based on International Classification of Diseases, Ninth Revision codes, which are assigned to charts by coders in a retrospective fashion. Coders rely on documentation of diagnoses in the medical record. We limited our selection of patients to those with a PE code listed as the principal reason for admission or as the secondary diagnosis if it followed respiratory failure or DVT as principal reasons. These were our attempts to ensure that included patients had documentation supporting a diagnosis of PE. We hope, but cannot ensure, that if a false-positive radiographic study was found or suspected, the clinical documentation would be changed so that coding would not assign PE. We presume that some cases of PE were diagnosed with radiographic modalities other than CT angiography. Unfortunately, we cannot ensure that some of these, regardless of radiographic modality, were not false-positive results.