Impairment severity in seizure disorders: some suggestions for reliable assessment.

Severity of impairment in seizure disorders is typically difficult to assess because of the existence of seizure-free intervals of varying duration, often in the absence of neurological or other clinical signs. For purposes of determining degree of severity, clear documentation and description of seizures, as well as of any associated phenomena such as loss of sphincter control and the side effects of medication, are needed. Differentiation between primary and secondary seizure disorders is also important because the latter frequently are associated with other impairments. The approach to assessment advocated is based on the incidence and intensity of seizures remaining after maximum therapeutic control has been achieved. An assessment form has been developed which concisely summarizes salient case features. A composite case report is appended for the purpose of demonstrating use of the form. Instructions are in the Appendix.