For their part, patents are an indicator of invention rather than innovation since not all patents are commercialised, and some types of technology are not patentable. The number and citation impact of scientific publications, or bibliometrics, is another output indicator which also has well-known limitations. This will require linking existing data sources and making better use of internationally comparable data at the firm, individual and organisation level. It will require the collection of additional material, as well as better understanding of currently unmeasured factors in the innovation process.