Many efficacy studies examining deep brain stimulation include only very small sample sizes. Why might this occur?
◦ Researchers aren't convinced it will work so they don't recruit many participants for their studies.
◦ Deep brain stimulation has long-term negative side effects that scare people away from participating.
◦ The surgery required to implant the electrodes for deep brain stimulation is invasive.
◦ The disorders targeted for treatment by DBS are so rare that it is difficult to find enough people to participate in a valid research study.