[Descriptive epidemiology of epilepsy]

More than 100 surveys in more than 30 countries have reported the incidence rate and/or prevalence rate for epilepsy. They have yielded conflicting figures, as well for crude as for specific rates. Some reasons for these discrepancies are analysed: lack of agreement on terminology concerning either epileptic seizures or epileptic syndromes, inclusion or exclusion of certain categories of patients and differences in sources of ascertainment, each of them exposing to some bias. In the state of the art, not a single study can be generalized to the entire population. However, almost all of them may be used with a cautious interpretation of results.