In a space of less than 24 hours, both "consensus science" and "evidence based medicine" have been mentioned on the Reform Club, and I gather from the comments sections that neither of these terms is being precisely understood.
"Consensus science" does not refer to the perfectly organic, Kuhnian process of scientific progress through hypothesis testing, replication, and peer review. While this process often does produce what might be termed 'consensus' on a body of theory, this is not what the term means. Consensus science is a particular process of reaching conclusions by committee. The rise of the scientific bureaucracies and the vastly increased interconnections between academic science and government that have grown up in the post World War II period have provided the culture medium that consensus science has colonized.
It's only important to produce a consensus if money is being handed out or regulations passed or actions forbidden on the basis of that consensus. From the 1950s through the late 80s these actions were typically intranational, of localized import -- the FDA allows a new drug on the market, NIH gives twenty million dollars to Johns Hopkins, that sort of thing. This changed in 1987 with the negotiation of the Montreal Protocol, an international agreement to phase out the production of chemicals that were thought to deplete stratospheric ozone.
The Montreal Protocol opened the door for similar treaty negotiations on the issue of global climate change. This happened despite the fact that the science underpinning Montreal had much more in common with the limited issues that had typified earlier consensus science than it did with the scientifically immature discipline of global climatology.
Evidence-based medicine is the clinical equivalent of consensus science: it's mass-produced medical treatment by anonymous committee. I am ashamed to admit that while my only role in consensus science has been mid-level onlooker (I was a GS-11 policy analyst at NSF for three years under Reagan and Bush 41) I have played an active, if minor, role in inflicting evidence-based medicine on American citizens. Evidence-based medicine, which sometimes travels under the alias 'best practices' is a centralized medical bureaucracy's attempt to ration care by only allowing those procedures approved by a committee of physicians. Paired with 'computerized medical records' -- another current bugabear that I was alarmed to hear mentioned in the SOTU speech -- you are moving towards having a computer tell your doctor what tests and treatments you should, may, and may not receive, based on running your computerized data through some algorithms coded by a couple of white coated eggheads at McMaster University. I know because I helped write some of them. I also helped design one of the main database applications that makes computerized medical results possible. I'm sorry. If it makes you feel any better, they didn't pay me very well.