More often than not, scientists are unable to reproduce medical research results. The lack of reproducibility is likely due to more complicated experiments as laboratory methods evolve, the use of different equipment and materials by different studies, the high number of variables present in a study, authors not presenting all information to other researchers, and escalating pressure for scientists and scientific publications to publish results. Positive results may be more likely to occur in academic studies, which generally are not blind. Pharmaceutical companies also tend to want to submit positive results. Drugmakers can lose millions of dollars if they fail to reproduce study results. Earlier this year, Bayer announced that it had scrapped almost two-thirds of its early-stage pharmaceutical projects because results did not replicate published studies. Venture capitalists have noted the lack of reproducibility as a reason they are hesitant to fund early-stage projects.

Source: The Wall Street Journal