Factors affecting the yield of pediatric EEGs in clinical practice

Clinical factors affecting the yield of 2500 pediatric electroencephalograms were analyzed. Electroencephalograms were interpreted as epileptiform in 40% of children with epilepsy. Most electroencephalograms were ordered for seizure in children not taking anti-epileptic drugs; just 15% showed epileptiform features. Six percent of electroencephalograms were epileptiform in non-seizure patients. The neurologist significantly influenced the odds of epileptiform interpretation (P = 0.022) and the recommendation to repeat the electroencephalogram (P < 0.001). In practice most electroencephalograms ordered for seizure are actually for non-seizure. In routine pediatric practice, electroencephalography has a low yield and appears to be over-used.