The evolution of health-related quality of life assessment in epilepsy.

The purpose of this article is to review the ways in which quality of life has been assessed in patients with epilepsy. It is specifically proposed that there have been three phases or types of studies examining the effects of epilepsy on cognitive, behavioural, social and physical function. The first and oldest phase was characterized by the use of traditional forms of clinical evaluation and available generic measures of cognitive, behavioural and psychosocial function to study the general effects of epilepsy, effects of epilepsy-specific clinical variables (e.g. seizure type, age at onset), and the consequences of treatment with antiepileptic medications on patients' lives. The second phase of research was characterized by the development of epilepsy-specific measures of cognitive ability, psychological status and psychosocial status, which were designed to meet the special research and clinical needs not provided by previous generic measures (e.g. Washington Psychosocial Seizure Inventory, Fear of Seizures Scale). The third and most recent phase is characterized by the use of models, techniques, and measures developed from the health services research field to assess formally contemporary definitions of health-related quality of life (HRQOL) (e.g. ESI-55, QOLIE-89, Seizure Severity Scale) and develop models of the effects of epilepsy on HRQOL. Thus, concern regarding the impact and consequences of epilepsy is not a new development, but has evolved over the years, resulting in new models and methods of assessment of disease impact on well-being and functional status.