The Centre for Science and Technology Studies (CWTS), Leiden University was commissioned by HEFCE to explore a series of key technical issues in producing bibliometrics indictors of research quality. These include approaches to defining subject groups and aggregating data, and sensitivity to methodological variations. The report builds on an earlier scoping study, and is intended to inform a pilot exercise to test methods of producing bibliometric indicators for the Research Excellence Framework.
CWTS found that coverage of the Web of Science is variable but generally good within science-related groups. There is a general correlation between normalised citation impact and RAE ratings, but this varies in different subjects. Further work may need to be carried out to develop a classification system based on journals rather than RAE units of assessment and on the assignment of staff to multiple categories. Using different parameters to construct indicators can have a significant effect on the outcomes.