We thank Dr. Catanzarite for his thoughtful commentary on our recent article.1 Although there are definite limitations to the use of large administrative databases such as the Nationwide Inpatient Sample, there are also significant benefits as well. The ability to study the care delivered at more than 4,000 hospitals across 48 states is a powerful tool.
With regard to 40% of patients being discharged undelivered, many patients may have suffered acute respiratory distress syndrome early in their pregnancies, and thus would not have delivered during the hospitalization. Transferred patients potentially could have been counted twice; however, the number of transferred patients in our cohort was less than 2%, thus limiting the effect on the overall mortality observed.
Chart reviews are an excellent method of studying rare problems in all types of medicine. They themselves are also fraught with certain limitations, such as generalizability. Notwithstanding, the power of large databases adds additional information, which, when interpreted in the context of the study design, allows further insights into the care of patients.