Seizure control as an indicator of therapeutic usefulness.

Seizure control, in addition to quality of life, is an important outcome after epilepsy surgery. However, seizure measurement is not straightforward. We explore some important difficulties in obtaining unbiased, reliable estimates of seizure frequency, and discuss aspects of data analysis as it pertains to validity and clinical meaningfulness. As seizure severity is an integral component of seizure outcome assessment, we discuss aspects of measurement of this outcome. Suggestions for improving validity are offered, based on the literature and on methodological common sense. Finally, we look at the Canadian perspective and the potential for adopting methodology that allows for data pooling and for more powerful analyses.