Many databases were searched, including MEDLINE, EMBASE, and Dissertation Abstracts, with no language restrictions, up to June to October 2003. Several journals were handsearched and experts were contacted.
There were four questions and studies of different designs were eligible for each question. Patients had to have refractory epilepsy and be under consideration for surgery. Any neuroimaging technique could be assessed, including magnetic resonance imaging (MRI), positron emission tomography (PET), and single-photon emission computed tomography (SPECT). The outcomes included seizure outcome, function, quality of life, and adverse events, among others.
Two reviewers assessed initial search results. One reviewer assessed full papers, extracted the data, and assessed quality, all of which were checked by a second reviewer. A narrative synthesis was reported, by imaging test.