IN AN exercise that threw up a surprise right at the top, one trend has remained constant: The steady rise of Singapore universities and institutions.
In the Nature Index 2015 Global, Nanyang Technological University (NTU) came in at No. 40, while the National University of Singapore (NUS) was at No. 42.
The Nature Index is a ranking by one of the world's most prestigious specialist research publications. It is in its second year.
It looks at the high-quality science output of 20,000 research institutions around the world, tracking the author affiliations of nearly 60,000 high-quality scientific articles published a year.
The top institution on the index was the Chinese Academy of Sciences in Beijing, while traditional powerhouse Harvard University came in second.
The rankings, announced on Wednesday, also saw NTU rank eighth among Asian institutions listed on the index, climbing four places from its previous 12th spot.
NTU also pulled ahead of top universities such as University College London, Japan's Tohoku University, Pennsylvania State University and Duke University.
The Agency for Science, Technology and Research (A*Star) moved up from 133rd to 107th.
Meanwhile, NUS slipped three places from 39th place last year to 42nd.
This makes NTU the highest- ranked Singapore institution on the index this year, after climbing two spots from where it was last year.
At the country level, Singapore moved up two places to 15th. The United States remained in first place.
NTU published 371 articles that gave it a score of 199.86 on the index, computed using a weighted formula. This is a 6.7 per cent increase over last year.
NUS and A*Star received scores of 190.30 and 100.33 respectively, with the former slipping 0.8 per cent, and the latter increasing 22.9 per cent.
"We are pleased that NUS is once again in the world's top 50 research institutions in the latest Nature Index, and we remain committed to growing the translational impact of our research," said NUS president Tan Chorh Chuan.
Based on faculty, NTU's chemistry research was ranked ninth internationally, up from 12th place previously. It surpassed other top institutions such as Harvard, University of California Berkeley, University of Oxford and University of Cambridge.
NTU also scored well in physical sciences, ranking 35th, up from 39th place.
The university's rapid rise could be attributed to its recruitment strategy, said NTU provost Freddy Boey.
"We went to top research departments globally and hired researchers in groups, so that when they came to Singapore, they had already formed research teams."