A science journalist sent 304 random variations of a deliberately and severely flawed paper to open access journals.
157 got accepted, 98 rejected with 49 pending. "... about 60% of the final decisions occurred with no sign of peer review" (pooling across accept and reject).
The article reads as a sting on open-access publishing in particular, but it is hard to know how closed-access publishing would have done under the same test.
http://www.sciencemag.org/content/342/6154/60.full
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