Sham exposure
It is important to note that the sham was also emitting RF radiation at a lower level, and that the reaction of participants to the sham exposure may also be related to EMFs 

I have no idea of the scientific consensus on this, but I've moved it from the article because of a) editorialising ("It is important to note") and b) unreliable sourcing (it just dips into BMJ Rapid Responses, which is no more than an online letters page, to a post by a person of unknown credentials).