In some cases, it is simply because we have no data in that category. For example, there are some effects that are specific to animal testing which would not appear in the other categories, and some drugs may be approved only in Europe, and thus would not be listed in the USFDA’s AERS database of post market reports. Some cases include drugs for which we have not yet been able to obtain data in a certain category due to, for example, a missing original approval package (most preclinical data, for example, is listed in the ‘Originator’ Approval Package listed in our system as “S-000”; if we do not have that document, the preclinical data for that drug may be limited to extracted journal data and data contained on the package insert).