The data come from the scientific literature and the NDA reviews of the FDA-approved products. The majority of articles are indexed by NCBI PubMed; however, some articles are obtained from Embase. Articles must be published in print or included in a finalized version of its respective online only journal issue in order for the data to be included in DIDB. Relevant online ahead of print articles included in PubMed or Embase are included in DIDB only after a print version is published.