ECT SEIZURE DURATION - RELIABILITY OF MANUAL AND COMPUTER-AUTOMATED DETERMINATIONS

Reliable monitoring of electroencephalographic (EEG) and electromyogra phic electroconvulsive therapy (ECT) seizure duration has become impor tant as these assessments have become a routine part of the clinical p ractice of ECT. In this regard, accurate automated seizure duration de terminations would be particularly valuable. As a result, the present study was performed to assess the reliability of available computer-au tomated determinations of seizure duration (Thymatron Model DGx ECT ma chine; Somatics, Inc.) and to explore the factors upon which such reli ability as well as the determinations of experienced raters depend. We found that the experienced human raters had very high interrater reli ability, significantly higher than either did with the automated Thyma tron DGx ratings. In general, the reliability of all ratings declined in the context of artifact, poor postictal suppression or an EEG seizu re end point that was reached gradually. Reliability was also greater for continuation ECT as compared with the index course. The reliabilit y of Thymatron DGx versus experienced human ratings was particularly s ensitive to these factors, ranging from 0.68 when several of these fac tors were simultaneously present to 0.999 when all these factors were absent.