The validation of a new ambulatory spike and wave monitor

The reliability of a new pocket-size ambulatory monitor designed to automatically detect, indicate, measure and store spike and wave episodes in the EEG was determined. Eleven teenage children with epilepsy were studied. All had spike and wave episodes that were around 3/sec in frequency. A double-blind trial was carried out in which 2 experienced encephalographers scored independently the simultaneous records of the monitor and EEG. Correlation coefficients were calculated and, taking into account any inconsistencies between the 2 scorers' sets of data, a validation based on unity was determined for the monitor's record for each child. Of the 11 children studied only one had a validity measure that was less than 0.9, suggesting that when correctly adjusted for each child the monitor gave a reliable automatic indication of the duration and number of spike and wave events.