A CASE-CONTROL STUDY ON ALCOHOL AND SEIZURES - STUDY DESIGN, PROTOCOL, AND DATA-COLLECTION

We designed a multicenter case control study to evaluate whether chron ic alcoholism and alcohol consumption ape risk factors for developing a first generalized tonic-clonic epileptic seizure. Cases were 278 pat ients (92 women, 186 men), with a first generalized tonic-clonic seizu re (either idiopathic or symptomatic), matched to 556 controls for cen ter, sex, age, and weekday of the seizure. Information on risk factors was obtained through a questionnaire. This paper focuses on the study design (selection of cases and choice of controls), the validity of t he instruments for data collection and the strategies of study conduct ion (interviews, use of proxy respondents). Inter-rater agreement was excellent for drinking status, patterns of drinking, and broad indicat ors of consumption (yes/no). Agreement was variable for the number of servings/week, but was excellent (r=0.91) for a summary measure of dai ly alcohol intake.