The test of replicability, as it’s known, is the foundation of modern research. Replicability is how the community enforces itself. It’s a safeguard for the creep of subjectivity. Most of the time, scientists know what results they want, and that can influence the results they get. The premise of replicability is that the scientific community can correct for these flaws.

But now all sorts of well-established, multiply confirmed findings have started to look increasingly uncertain. It’s as if our facts were losing their truth: claims that have been enshrined in textbooks are suddenly unprovable. This phenomenon doesn’t yet have an official name, but it’s occurring across a wide range of fields, from psychology to ecology. In the field of medicine, the phenomenon seems extremely widespread, affecting not only antipsychotics but also therapies ranging from cardiac stents to Vitamin E and antidepressants: Davis has a forthcoming analysis demonstrating that the efficacy of antidepressants has gone down as much as threefold in recent decades.

For many scientists, the effect is especially troubling because of what it exposes about the scientific process. If replication is what separates the rigor of science from the squishiness of pseudoscience, where do we put all these rigorously validated findings that can no longer be proved?

via The decline effect and the scientific method : The New Yorker.

This is the second time scientific results are being questioned on a very deep level in a very short time. It’s a very disturbing trend.

In just the last two months, two pillars of preventive medicine fell. A major study concluded there’s no good evidence that statins drugs like Lipitor and Crestor help people with no history of heart disease. The study, by the Cochrane Collaboration, a global consortium of biomedical experts, was based on an evaluation of 14 individual trials with 34,272 patients. Cost of statins: more than $20 billion per year, of which half may be unnecessary. Pfizer, which makes Lipitor, responds in part that “managing cardiovascular disease risk factors is complicated”. In November a panel of the Institute of Medicine concluded that having a blood test for vitamin D is pointless: almost everyone has enough D for bone health 20 nanograms per milliliter without taking supplements or calcium pills. Cost of vitamin D: $425 million per year.

Ioannidis, 45, didn’t set out to slay medical myths. A child prodigy he was calculating decimals at age 3 and wrote a book of poetry at 8, he graduated first in his class from the University of Athens Medical School, did a residency at Harvard, oversaw AIDS clinical trials at the National Institutes of Health in the mid-1990s, and chaired the department of epidemiology at Greece’s University of Ioannina School of Medicine. But at NIH Ioannidis had an epiphany. “Positive” drug trials, which find that a treatment is effective, and “negative” trials, in which a drug fails, take the same amount of time to conduct. “But negative trials took an extra two to four years to be published,” he noticed. “Negative results sit in a file drawer, or the trial keeps going in hopes the results turn positive.” With billions of dollars on the line, companies are loath to declare a new drug ineffective. As a result of the lag in publishing negative studies, patients receive a treatment that is actually ineffective. That made Ioannidis wonder, how many biomedical studies are wrong?

His answer, in a 2005 paper: “the majority.”

via Why Almost Everything You Hear About Medicine Is Wrong – Newsweek.