A case-control study on alcohol and seizures: study design, protocol, and data collection

We designed a multicenter case control study to evaluate whether chronic alcoholism and alcohol consumption are risk factors for developing a first generalized tonic-clonic epileptic seizure. Cases were 278 patients (92 women, 186 men), with a first generalized tonic-clonic seizure (either idiopathic or symptomatic), matched to 556 controls for center, 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 the instruments for data collection, and the strategies of study conduction (interviews, use of proxy respondents). Inter-rater agreement was excellent for drinking status, patterns of drinking, and broad indicators of consumption (yes/no). Agreement was variable for the number of servings/week, but was excellent (r=0.91) for a summary measure of daily alcohol intake.Members of the ALC.E. Group:Sironi L.,U.O. di Neurologia, Ospedale Regionale, Aosta; Brignolio F., Duc E., Montano V., Tribolo A.,Divisione di Neurologia, Ospedale Civile, Asti; Nardozza V., Gionco M.,Divisione di Neurologia, Ospedale degli Infermi, Biella; Grasso E., Meineri P., Rosso M.G.,Divisione di Neurologia, Ospedale Santa Croce, Cuneo; Villani A., Margaroli A., Julita P., Savoini G.,Divisione di Neurologia, Ospedale S. Biagio, Domodossola; Cavalli A., De Angelis M.S., Naldi P., Terazzi E., Tinebra M.,Divisione Universitaria di Neurologia, Facoltà di Medicina e Chirurgia di Novara, Università di Torino; Campanella A., De Mattei M., Rocci E., Zaina P.,DEA di Neurologia, Ospedale Molinette, Torino; Nobili M., Vivalda L., Leotta D., Morino U.,Divisione di Neurologia, Ospedale Martini, Torino; Bacci R., Daniele D.,Divisione di Neurologia, Ospedale Mauriziano, Torino; Rubino R., Provera P.,Divisione di Neurologia, Ospedale Civile, Tortona; Andreotti M., Mittino D.,Divisione di Neurologia, Ospedale SS. Trinità, Varallo Sesia.