Most clinical research is not useful to clinicians. This could change.Many billions of dollars are spent on clinical research every year, yet much of the knowledge produced is not useful for guiding clinical decision making. Because many of the features that make clinical research reliable as a basis for clinical practice can be identified, more useful clinical research could easily be produced at the same or even at massively reduced cost, according to John Ioannidis from Stanford University, US, in an Essay published in PLOS Medicine.

