Epidemiologic Aspects of Epilepsy

To the Editor. —Epilepsy, one of the oldest identified neurologic diseases, is now recognized as a major public health problem all over the world.' No reliable investigative tool is available that can diagnose or exclude the possibility of epilepsy. However, an electroencephalogram has been frequently used in conjunction with meticulous history in the diagnosis and differential diagnosis, and sometimes in knowing the type of seizures. The study of epidemiology is beset with problems since epilepsy is often a hidden disease.2This makes the statistics concerning the prevalence and incidence of epilepsy difficult to interpret.3In cooperation with the US National Institutes of Health, the World Health Organization developed a protocol to measure the prevalence of epilepsy.4Using this protocol, the investigations have been carried out in the United States and Nigeria, and smaller pilot studies have been conducted in the Peoples Republic of China, Chile, Colombia, Ecuador