The discipline in question would dictate the need for more or less currency. Fast moving fields produce more new information and need more frequent updates. For example, research in Immunology or Genetics moves at a decidedly faster pace than research into early modern Milanese liturgical music. Nonetheless, because the Web environment is an environment of change not stasis, a six month interval is the maximum acceptable period between updates regardless of discipline. As selection criteria develop and the core of selected Web sites grows, this interval may shorten.
Functionality is of primary importance here.
Whatever the level of technology employed, it must function well and allow the user to progress logically through the information. Likewise, the arrangement of elements when viewed in a browser window should serve to make the purpose of the site more obvious. If a site provides its own mission or scope statement, the editor verifies that the content matches this statement. The ISI scope statement is based, then, on what the ISI editor has observed to be the actual scope of the site. Primarily, ISI is looking for scholarly, research-oriented material, or material of interest to the research community.