This week, Nature Publishing Group introduces the Nature Index. The platform is a database of the contributions made by the world’s research institutions to articles published in 68 leading scientific journals (see for a freely accessible 12-month data set). The journals were chosen by an independent panel of researchers drawn from across the natural sciences (see, with further validation from a large online survey of active scientists. The index offers various options for counting and attributing contributions.

The launch is in the spirit of a beta-test — readers can analyse and interpret the data for themselves, and assess the Nature Index’s strengths and weaknesses. The methodology behind the index is explained in the accompanying Nature supplement (page S52), as are the caveats that need to be considered when analysing and interpreting the data.

The journals were selected in 2011. Their outputs have been tracked in subsequent years, and the database will initially be updated monthly. Some journals that might now be strong contenders for inclusion, but were only newly established at that time (including one of the Nature research journals, Nature Climate Change), were not selected by the panel. Subject to the feedback we receive, we expect to review the list of journals next year.

We anticipate diverse opinions on many aspects of the Nature Index. Constructive suggestions for improvement are particularly welcome. The supplement includes tables that summarize patterns of research output in the Nature Index for institutions and countries, but these tables are not themselves the Index — rather, they are just some of the possible ways of displaying patterns in a snapshot of data encompassing the most recent complete calendar year.

Used carefully, with proper consideration of the strengths and limits of the underlying data, we believe that the Nature Index can contribute to an understanding of significant scientific outputs at the institutional, country and regional levels. We invite feedback, which should be posted at