US institutions dominate Nature research index
Harvard, the Massachusetts Institute of Technology, Stanford and the 25 components of the US National Institutes of Health led the list of the top 200 research institutions from around the world.
But Germany's Max Planck Society, which incorporates 56 separate institutes, was in fifth spot with the Chinese Academy of Sciences rated sixth by counting the contributions from its 54 science institutes.
The index, published as a supplement to Nature, measures the output of research from nations and institutes in terms of publications in the 18 Nature-branded primary research journals in 2013.
Institutions are ranked according to the number of primary research articles they publish in the journals, which are world-renowned as the pre-eminent platform for publication of the best international research.
The index compilers note that there are many ways to assess the research output of institutions and that the index "is just one that should be used alongside many".
"Users can drill down to find the abstracts of individual papers that make up the index allowing deep analysis of where some of the best research across a broad range of fields is coming from. However, there are caveats that must be applied in interpreting the index.
"For instance, Nature journals, although covering a broad spectrum of basic research in the life sciences, physical and chemical sciences, provide relatively limited coverage of applied sciences, engineering and clinical medicine. The index should therefore be viewed as primarily an index of high quality basic and not applied research."
The Asia-Pacific region
As well as the global rankings, Nature also publishes separate reports and listings of the top research institutions in the Asia-Pacific Region, as well as individual accounts of those in Australia, China, Japan and Korea.
The Asia-Pacific summary includes details of institutional and country rankings by journal and subject, along with historical rankings and graphs. In this case, the index tracks research published in Nature journals over the past 12 months and is updated weekly.
It therefore offers many different options for users to delve into the data, enabling them to analyse results according to institution, country, subject or journal while they can also obtain listings of recently published articles.
"The governments of many Asia-Pacific countries see increasing their high quality scientific output as essential to building an innovative, globally competitive, knowledge-based economy," the Nature editors say. "And the data compiled in this index show that the region is making progress towards this goal."
But they also note that while for many years science in the Asia-Pacific region has been dominated by Japan, "as seen through the lens of the index", the fastest growth in high-quality research is now coming from other countries - in particular China and Singapore.
At the same time, though, Japan is still the leader in the Asia-Pacific and the most prolific at publishing papers in Nature itself.
But the editors also point to the fact that Japan's contributions are drawn from a smaller proportion of international collaborations than any other major Asia-Pacific nation.
"With a limited capacity to raise research funding, if Japan wishes to build on its legacy then high-level international collaboration must surely be a priority," they write.
Nick Campbell, head of the Nature Publishing Group for Greater China, says it is that vastly populated nation which is driving the pattern of growth and, for the first time, China "boasts the top Asia-Pacific institutional contributor to the index: the Chinese Academy of Sciences.
"However, the giant player's output is increasing at a slower rate in the index than smaller players like Singapore and South Korea," Campbell says. "It also falls a long way behind Singapore and Australia in its contribution relative to its number of researchers.
"Important science figures in China are aware of its shortfalls and of what it needs to improve upon, and the country's ambition matches its growth. High profile achievements like its recent successful lunar mission coupled with its continuing commitment to increase spending in research will no doubt bear significant fruit in years to come."
Campbell says the other Asia-Pacific "behemoth", India, needs to go much further before it challenges the top contributors. India's flagship technological achievements and investment proposals, however, "do provide some hope that it might start to see the sort of gains that China has over the past five years".
"Asia-Pacific will continue to be an engine of growth for quality research output. And, if the giants of the region, China and India, can match the efficiency of smaller nations like Singapore and Australia, the effect on global science and innovation will be truly transformative," he concludes.
Despite its relatively small population, Australia retains third place in the Asia-Pacific region, with its greatest strengths in earth and environmental sciences.
Compared with 2012, Australia improved its 2013 score by almost every measure, with the second highest level of international collaboration in the region. Its contribution to Nature journals grew by more than 50% last year.
In the life sciences, Australia ranks third in the Asia-Pacific index behind China and Japan although it is persistently strong in immunology and four of the top five regional institutions contributing to the Nature Immunology journal were Australian.
The University of Melbourne held top spot in Australia for the third consecutive year, followed by Australian National University and the University of Queensland in second and third places, respectively - the same positions as in 2012. Overall, Australia had 29 institutions in the Asia-Pacific Top 200, with Melbourne ranked at number eight.
Australia's main science body, the Commonwealth Scientific and Industrial Research Organisation, or CSIRO, dropped to seventh from fifth place in the latest index despite increased output.
But the CSIRO was also the top Asia-Pacific contributor to Nature Climate Change, with 12 papers that included subjects such as climate change models and the effects of a changing climate on species distribution.