Three Reasons to Distrust Microarray Results
This post originally appeared on the Software Carpentry website.
...the paper actually demonstrated that is it possible to distinguish microarray experiments conducted on one day from experiments conducted another day. That is, batch effects from the lab were much larger than differences between patients who did and did not respond to therapy... As is so often the case, data were mislabeled. In fact, 3/4 of the samples were mislabeled.