Sources without a CiteScore value: more clarity is required

In December 2016, Elsevier launched CiteScore, a new indicator of a journal´s impact based on similar principles as the journal impact factor but improving some issues that had been raised about the latter. The inclusion of all document types, an extension on the period of time for its calculation and the access of CiteScore free of charge made this indicator more transparent and comprehensive. However, many sources display “N/A” instead of a CiteScore value. Since no explanation has been provided by Scopus regarding the significance of this abbreviation form, all the sources categorized by Scopus under the sub-subject category “Library and Information Science” were examined. This study shows that 78 sources that displayed the abbreviation form included sources that had been discontinued, others that had a name change, some that had recently been indexed by Scopus and one particular journal that has been covered by Scopus since 2000 that unexplainably has not been assigned a CiteScore. Certainly, explaining the complex use of this abbreviation form would improve the clarity of CiteScore. In fact, it would be advisable to use different abbreviation forms to denote the reasons why any given indexed journal has not been assigned a CiteScore value.