No confirmation of visual evoked potential diagnostic test for migraine. We have attempted to replicate the results of studies on a diagnostic test reported to have 90% sensitivity and 89-96% specificity for migraine. The technique is based on peak-to-peak measurements of fast background electroencephalographic activity during a visual evoked potential (VEP) study. VEP latencies and amplitudes did not differ significantly, and showed substantial overlap, between a group of eight migraine patients and ten age-matched healthy controls. We could not recognise previously described fast activity or measure it objectively by peak-to-peak measurements. We cannot confirm that measurement of fast wave activity in the VEP background is useful in diagnosis of migraine. 