Day by day variations of the amount of spike-wave activity in 24 hour cassette recordings

For interpretation of mobile long-term EEG monitoring in patients suffering from absence epilepsies with regular spike-wave (S-W) paroxysms, the fluctuating amount of this parameter has to be taken into account if, for example, therapeutic effects are to be judged. An 'S-W variogram' is derived resembling the statistical properties of the day by day variability as an orienting criterion in this respect.